Add benchmark for transliteration

Closes #11993

.circleci/config.yml

@@ -4,7 +4,7 @@ parameters:
 defaults: &defaults
   resource_class: large
   docker:
-      - image: bepsays/ci-hugoreleaser:1.22000.20100
+      - image: bepsays/ci-hugoreleaser:1.22100.20600
 environment: &buildenv
       GOMODCACHE: /root/project/gomodcache
 version: 2
@@ -60,7 +60,7 @@ jobs:
     environment:
         <<: [*buildenv]
     docker:
-    - image: bepsays/ci-hugoreleaser-linux-arm64:1.22000.20100
+    - image: bepsays/ci-hugoreleaser-linux-arm64:1.22100.20600
     steps:
       - *restore-cache
       - &attach-workspace

.github/workflows/test-dart-sass-v1.yml

@@ -30,7 +30,7 @@ jobs:
           **/go.sum
           **/go.mod
     - name: Install Ruby
-      uses: ruby/setup-ruby@ee2113536afb7f793eed4ce60e8d3b26db912da4
+      uses: ruby/setup-ruby@036ef458ddccddb148a2b9fb67e95a22fdbf728b
       with:
         ruby-version: '2.7' 
         bundler-cache: true #

.github/workflows/test.yml

@@ -32,7 +32,7 @@ jobs:
           **/go.sum
           **/go.mod
     - name: Install Ruby
-      uses: ruby/setup-ruby@ee2113536afb7f793eed4ce60e8d3b26db912da4
+      uses: ruby/setup-ruby@036ef458ddccddb148a2b9fb67e95a22fdbf728b
       with:
         ruby-version: '2.7'
         bundler-cache: true #
@@ -58,11 +58,11 @@ jobs:
         brew install pandoc
     - if: matrix.os == 'windows-latest'
       run: |
-        Choco-Install -PackageName pandoc
+        choco install pandoc
     - run: pandoc -v
     - if: matrix.os == 'windows-latest'
       run: |
-        Choco-Install -PackageName mingw -ArgumentList "--version","12.2.0","--allow-downgrade"
+        choco install mingw
     - if: matrix.os == 'ubuntu-latest'
       name: Install dart-sass Linux
       run: |
@@ -87,6 +87,12 @@ jobs:
         curl -LJO "https://github.com/sass/dart-sass/releases/download/${env:SASS_VERSION}/dart-sass-${env:SASS_VERSION}-windows-x64.zip";
         Expand-Archive -Path "dart-sass-${env:SASS_VERSION}-windows-x64.zip" -DestinationPath .;
         echo  "$env:GITHUB_WORKSPACE/dart-sass/" | Out-File -FilePath $Env:GITHUB_PATH -Encoding utf-8 -Append
+    - if: matrix.os == 'ubuntu-latest'
+      name: Install staticcheck
+      run: go install honnef.co/go/tools/cmd/staticcheck@latest
+    - if: matrix.os == 'ubuntu-latest'
+      name: Run staticcheck
+      run: staticcheck ./...
     - if: matrix.os != 'windows-latest'
       name: Check
       run: |

CONTRIBUTING.md

@@ -122,8 +122,6 @@ cd hugo
 go install
 ```
 
->Note: Some Go tools may not be fully updated to support Go Modules yet. One example would be LiteIDE. Follow [this workaround](https://github.com/visualfc/liteide/issues/986#issuecomment-428117702) for how to continue to work with Hugo below `GOPATH`.
-
 For some convenient build and test targets, you also will want to install Mage:
 
 ```bash

README.md

@@ -33,7 +33,7 @@ A fast and flexible static site generator built with love by [bep], [spf13], and
 [![Tests on Linux, MacOS and Windows](https://github.com/gohugoio/hugo/workflows/Test/badge.svg)](https://github.com/gohugoio/hugo/actions?query=workflow%3ATest)
 [![Go Report Card](https://goreportcard.com/badge/github.com/gohugoio/hugo)](https://goreportcard.com/report/github.com/gohugoio/hugo)
 
-[Website] | [Installation] | [Documentation] | [Support] | [Contributing] | [Twitter]
+[Website] | [Installation] | [Documentation] | [Support] | [Contributing] | <a rel="me" href="https://fosstodon.org/@gohugoio">Mastodon</a>
 
 ## Overview
 
@@ -84,8 +84,8 @@ Hugo is available in two editions: standard and extended. With the extended edit
 
 Prerequisites to build Hugo from source:
 
-- Standard edition: Go 1.19 or later
-- Extended edition: Go 1.19 or later, and GCC
+- Standard edition: Go 1.20 or later
+- Extended edition: Go 1.20 or later, and GCC
 
 Build the standard edition:
 
@@ -142,40 +142,40 @@ Hugo stands on the shoulders of great open source libraries. Run `hugo env --log
 
 ```text
 cloud.google.com/go/compute/metadata="v0.2.3"
-cloud.google.com/go/iam="v1.1.0"
-cloud.google.com/go/storage="v1.30.1"
-cloud.google.com/go="v0.110.2"
-github.com/Azure/azure-sdk-for-go/sdk/azcore="v1.6.1"
+cloud.google.com/go/iam="v1.1.3"
+cloud.google.com/go/storage="v1.31.0"
+cloud.google.com/go="v0.110.8"
+github.com/Azure/azure-sdk-for-go/sdk/azcore="v1.7.0"
 github.com/Azure/azure-sdk-for-go/sdk/azidentity="v1.3.0"
 github.com/Azure/azure-sdk-for-go/sdk/internal="v1.3.0"
-github.com/Azure/azure-sdk-for-go/sdk/storage/azblob="v1.0.0"
+github.com/Azure/azure-sdk-for-go/sdk/storage/azblob="v1.1.0"
 github.com/Azure/go-autorest/autorest/to="v0.4.0"
 github.com/AzureAD/microsoft-authentication-library-for-go="v1.0.0"
 github.com/BurntSushi/locker="v0.0.0-20171006230638-a6e239ea1c69"
 github.com/PuerkitoBio/purell="v1.1.1"
 github.com/PuerkitoBio/urlesc="v0.0.0-20170810143723-de5bf2ad4578"
-github.com/alecthomas/chroma/v2="v2.7.0"
+github.com/alecthomas/chroma/v2="v2.11.1"
 github.com/armon/go-radix="v1.0.0"
-github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream="v1.4.10"
-github.com/aws/aws-sdk-go-v2/config="v1.18.27"
-github.com/aws/aws-sdk-go-v2/credentials="v1.13.26"
-github.com/aws/aws-sdk-go-v2/feature/ec2/imds="v1.13.4"
-github.com/aws/aws-sdk-go-v2/feature/s3/manager="v1.11.70"
-github.com/aws/aws-sdk-go-v2/internal/configsources="v1.1.34"
-github.com/aws/aws-sdk-go-v2/internal/endpoints/v2="v2.4.28"
-github.com/aws/aws-sdk-go-v2/internal/ini="v1.3.35"
-github.com/aws/aws-sdk-go-v2/internal/v4a="v1.0.26"
-github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding="v1.9.11"
-github.com/aws/aws-sdk-go-v2/service/internal/checksum="v1.1.29"
-github.com/aws/aws-sdk-go-v2/service/internal/presigned-url="v1.9.28"
-github.com/aws/aws-sdk-go-v2/service/internal/s3shared="v1.14.3"
-github.com/aws/aws-sdk-go-v2/service/s3="v1.35.0"
-github.com/aws/aws-sdk-go-v2/service/sso="v1.12.12"
-github.com/aws/aws-sdk-go-v2/service/ssooidc="v1.14.12"
-github.com/aws/aws-sdk-go-v2/service/sts="v1.19.2"
-github.com/aws/aws-sdk-go-v2="v1.18.1"
-github.com/aws/aws-sdk-go="v1.44.284"
-github.com/aws/smithy-go="v1.13.5"
+github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream="v1.4.11"
+github.com/aws/aws-sdk-go-v2/config="v1.18.32"
+github.com/aws/aws-sdk-go-v2/credentials="v1.13.31"
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds="v1.13.7"
+github.com/aws/aws-sdk-go-v2/feature/s3/manager="v1.11.76"
+github.com/aws/aws-sdk-go-v2/internal/configsources="v1.1.37"
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2="v2.4.31"
+github.com/aws/aws-sdk-go-v2/internal/ini="v1.3.38"
+github.com/aws/aws-sdk-go-v2/internal/v4a="v1.1.0"
+github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding="v1.9.12"
+github.com/aws/aws-sdk-go-v2/service/internal/checksum="v1.1.32"
+github.com/aws/aws-sdk-go-v2/service/internal/presigned-url="v1.9.31"
+github.com/aws/aws-sdk-go-v2/service/internal/s3shared="v1.15.0"
+github.com/aws/aws-sdk-go-v2/service/s3="v1.38.1"
+github.com/aws/aws-sdk-go-v2/service/sso="v1.13.1"
+github.com/aws/aws-sdk-go-v2/service/ssooidc="v1.15.1"
+github.com/aws/aws-sdk-go-v2/service/sts="v1.21.1"
+github.com/aws/aws-sdk-go-v2="v1.20.0"
+github.com/aws/aws-sdk-go="v1.48.2"
+github.com/aws/smithy-go="v1.14.0"
 github.com/bep/clocks="v0.5.0"
 github.com/bep/debounce="v1.2.0"
 github.com/bep/gitmap="v1.1.2"
@@ -183,45 +183,45 @@ github.com/bep/goat="v0.5.0"
 github.com/bep/godartsass/v2="v2.0.0"
 github.com/bep/godartsass="v1.2.0"
 github.com/bep/golibsass="v1.1.1"
-github.com/bep/gowebp="v0.2.0"
+github.com/bep/gowebp="v0.3.0"
 github.com/bep/lazycache="v0.2.0"
-github.com/bep/logg="v0.2.0"
+github.com/bep/logg="v0.3.0"
 github.com/bep/mclib="v1.20400.20402"
 github.com/bep/overlayfs="v0.6.0"
 github.com/bep/simplecobra="v0.3.2"
 github.com/bep/tmc="v0.5.1"
-github.com/clbanning/mxj/v2="v2.5.7"
+github.com/clbanning/mxj/v2="v2.7.0"
 github.com/cli/safeexec="v1.0.1"
 github.com/cpuguy83/go-md2man/v2="v2.0.2"
 github.com/disintegration/gift="v1.2.1"
 github.com/dlclark/regexp2="v1.10.0"
 github.com/dustin/go-humanize="v1.0.1"
-github.com/evanw/esbuild="v0.18.5"
-github.com/fatih/color="v1.15.0"
-github.com/frankban/quicktest="v1.14.5"
-github.com/fsnotify/fsnotify="v1.6.0"
-github.com/getkin/kin-openapi="v0.118.0"
+github.com/evanw/esbuild="v0.19.7"
+github.com/fatih/color="v1.16.0"
+github.com/frankban/quicktest="v1.14.6"
+github.com/fsnotify/fsnotify="v1.7.0"
+github.com/getkin/kin-openapi="v0.120.0"
 github.com/ghodss/yaml="v1.0.0"
 github.com/go-openapi/jsonpointer="v0.19.6"
-github.com/go-openapi/swag="v0.22.3"
+github.com/go-openapi/swag="v0.22.4"
 github.com/gobuffalo/flect="v1.0.2"
 github.com/gobwas/glob="v0.2.3"
-github.com/gohugoio/go-i18n/v2="v2.1.3-0.20210430103248-4c28c89f8013"
+github.com/gohugoio/go-i18n/v2="v2.1.3-0.20230805085216-e63c13218d0e"
 github.com/gohugoio/locales="v0.14.0"
 github.com/gohugoio/localescompressed="v1.0.1"
 github.com/golang-jwt/jwt/v4="v4.5.0"
 github.com/golang/groupcache="v0.0.0-20210331224755-41bb18bfe9da"
 github.com/golang/protobuf="v1.5.3"
-github.com/google/go-cmp="v0.5.9"
-github.com/google/s2a-go="v0.1.4"
-github.com/google/uuid="v1.3.0"
+github.com/google/go-cmp="v0.6.0"
+github.com/google/s2a-go="v0.1.7"
+github.com/google/uuid="v1.4.0"
 github.com/google/wire="v0.5.0"
-github.com/googleapis/enterprise-certificate-proxy="v0.2.5"
-github.com/googleapis/gax-go/v2="v2.11.0"
-github.com/gorilla/websocket="v1.5.0"
-github.com/hairyhenderson/go-codeowners="v0.3.0"
+github.com/googleapis/enterprise-certificate-proxy="v0.3.2"
+github.com/googleapis/gax-go/v2="v2.12.0"
+github.com/gorilla/websocket="v1.5.1"
+github.com/hairyhenderson/go-codeowners="v0.4.0"
 github.com/hashicorp/golang-lru/v2="v2.0.1"
-github.com/invopop/yaml="v0.1.0"
+github.com/invopop/yaml="v0.2.0"
 github.com/jdkato/prose="v1.2.1"
 github.com/jmespath/go-jmespath="v0.4.0"
 github.com/josharian/intern="v1.0.0"
@@ -230,9 +230,9 @@ github.com/kr/text="v0.2.0"
 github.com/kylelemons/godebug="v1.1.0"
 github.com/kyokomi/emoji/v2="v2.2.12"
 github.com/mailru/easyjson="v0.7.7"
-github.com/marekm4/color-extractor="v1.2.0"
+github.com/marekm4/color-extractor="v1.2.1"
 github.com/mattn/go-colorable="v0.1.13"
-github.com/mattn/go-isatty="v0.0.19"
+github.com/mattn/go-isatty="v0.0.20"
 github.com/mattn/go-runewidth="v0.0.9"
 github.com/mitchellh/hashstructure="v1.1.0"
 github.com/mitchellh/mapstructure="v1.5.0"
@@ -240,51 +240,53 @@ github.com/mohae/deepcopy="v0.0.0-20170929034955-c48cc78d4826"
 github.com/muesli/smartcrop="v0.3.0"
 github.com/niklasfasching/go-org="v1.7.0"
 github.com/olekukonko/tablewriter="v0.0.5"
-github.com/pelletier/go-toml/v2="v2.0.8"
-github.com/perimeterx/marshmallow="v1.1.4"
+github.com/pelletier/go-toml/v2="v2.1.0"
+github.com/perimeterx/marshmallow="v1.1.5"
 github.com/pkg/browser="v0.0.0-20210911075715-681adbf594b8"
 github.com/pkg/errors="v0.9.1"
-github.com/rogpeppe/go-internal="v1.10.1-0.20230508101108-a4f6fabd84c5"
+github.com/rogpeppe/go-internal="v1.11.0"
 github.com/russross/blackfriday/v2="v2.1.0"
 github.com/rwcarlsen/goexif="v0.0.0-20190401172101-9e8deecbddbd"
 github.com/sanity-io/litter="v1.5.5"
-github.com/sass/dart-sass/compiler="1.63.6"
-github.com/sass/dart-sass/implementation="1.63.6"
-github.com/sass/dart-sass/protocol="2.1.0"
+github.com/sass/dart-sass/compiler="1.63.2"
+github.com/sass/dart-sass/implementation="1.63.2"
+github.com/sass/dart-sass/protocol="2.0.0"
 github.com/sass/libsass="3.6.5"
-github.com/spf13/afero="v1.9.5"
+github.com/spf13/afero="v1.10.0"
 github.com/spf13/cast="v1.5.1"
 github.com/spf13/cobra="v1.7.0"
 github.com/spf13/fsync="v0.9.0"
 github.com/spf13/pflag="v1.0.5"
-github.com/tdewolff/minify/v2="v2.12.7"
-github.com/tdewolff/parse/v2="v2.6.6"
-github.com/webmproject/libwebp="v1.2.4"
-github.com/yuin/goldmark="v1.5.4"
+github.com/tdewolff/minify/v2="v2.20.7"
+github.com/tdewolff/parse/v2="v2.7.5"
+github.com/webmproject/libwebp="v1.3.2"
+github.com/yuin/goldmark-emoji="v1.0.2"
+github.com/yuin/goldmark="v1.6.0"
 go.opencensus.io="v0.24.0"
 go.uber.org/atomic="v1.11.0"
-go.uber.org/automaxprocs="v1.5.2"
-gocloud.dev="v0.30.0"
-golang.org/x/crypto="v0.10.0"
-golang.org/x/exp="v0.0.0-20230321023759-10a507213a29"
-golang.org/x/image="v0.8.0"
-golang.org/x/mod="v0.10.0"
-golang.org/x/net="v0.11.0"
-golang.org/x/oauth2="v0.9.0"
-golang.org/x/sync="v0.3.0"
-golang.org/x/sys="v0.9.0"
-golang.org/x/text="v0.10.0"
-golang.org/x/tools="v0.9.3"
+go.uber.org/automaxprocs="v1.5.3"
+gocloud.dev="v0.34.0"
+golang.org/x/crypto="v0.15.0"
+golang.org/x/exp="v0.0.0-20221031165847-c99f073a8326"
+golang.org/x/image="v0.13.0"
+golang.org/x/mod="v0.14.0"
+golang.org/x/net="v0.18.0"
+golang.org/x/oauth2="v0.13.0"
+golang.org/x/sync="v0.5.0"
+golang.org/x/sys="v0.14.0"
+golang.org/x/text="v0.14.0"
+golang.org/x/time="v0.3.0"
+golang.org/x/tools="v0.15.0"
 golang.org/x/xerrors="v0.0.0-20220907171357-04be3eba64a2"
-google.golang.org/api="v0.128.0"
-google.golang.org/appengine="v1.6.7"
-google.golang.org/genproto/googleapis/api="v0.0.0-20230530153820-e85fd2cbaebc"
-google.golang.org/genproto/googleapis/rpc="v0.0.0-20230530153820-e85fd2cbaebc"
-google.golang.org/genproto="v0.0.0-20230530153820-e85fd2cbaebc"
-google.golang.org/grpc="v1.56.0"
-google.golang.org/protobuf="v1.30.0"
+google.golang.org/api="v0.151.0"
+google.golang.org/genproto/googleapis/api="v0.0.0-20231016165738-49dd2c1f3d0b"
+google.golang.org/genproto/googleapis/rpc="v0.0.0-20231030173426-d783a09b4405"
+google.golang.org/genproto="v0.0.0-20231016165738-49dd2c1f3d0b"
+google.golang.org/grpc="v1.59.0"
+google.golang.org/protobuf="v1.31.0"
 gopkg.in/yaml.v2="v2.4.0"
 gopkg.in/yaml.v3="v3.0.1"
+howett.net/plist="v1.0.0"
 software.sslmate.com/src/go-pkcs12="v0.2.0"
 ```
 </details>

cache/dynacache/dynacache.go

@@ -0,0 +1,582 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package dynacache
+
+import (
+	"context"
+	"fmt"
+	"math"
+	"path"
+	"regexp"
+	"runtime"
+	"sync"
+	"time"
+
+	"github.com/bep/lazycache"
+	"github.com/bep/logg"
+	"github.com/gohugoio/hugo/common/collections"
+	"github.com/gohugoio/hugo/common/herrors"
+	"github.com/gohugoio/hugo/common/loggers"
+	"github.com/gohugoio/hugo/common/paths"
+	"github.com/gohugoio/hugo/common/rungroup"
+	"github.com/gohugoio/hugo/config"
+	"github.com/gohugoio/hugo/helpers"
+	"github.com/gohugoio/hugo/identity"
+	"github.com/gohugoio/hugo/resources/resource"
+)
+
+const minMaxSize = 10
+
+// New creates a new cache.
+func New(opts Options) *Cache {
+	if opts.CheckInterval == 0 {
+		opts.CheckInterval = time.Second * 2
+	}
+
+	if opts.MaxSize == 0 {
+		opts.MaxSize = 100000
+	}
+	if opts.Log == nil {
+		panic("nil Log")
+	}
+
+	if opts.MinMaxSize == 0 {
+		opts.MinMaxSize = 30
+	}
+
+	stats := &stats{
+		opts:             opts,
+		adjustmentFactor: 1.0,
+		currentMaxSize:   opts.MaxSize,
+		availableMemory:  config.GetMemoryLimit(),
+	}
+
+	infol := opts.Log.InfoCommand("dynacache")
+
+	evictedIdentities := collections.NewStack[identity.Identity]()
+
+	onEvict := func(k, v any) {
+		if !opts.Running {
+			return
+		}
+		identity.WalkIdentitiesShallow(v, func(level int, id identity.Identity) bool {
+			evictedIdentities.Push(id)
+			return false
+		})
+		resource.MarkStale(v)
+	}
+
+	c := &Cache{
+		partitions:        make(map[string]PartitionManager),
+		onEvict:           onEvict,
+		evictedIdentities: evictedIdentities,
+		opts:              opts,
+		stats:             stats,
+		infol:             infol,
+	}
+
+	c.stop = c.start()
+
+	return c
+}
+
+// Options for the cache.
+type Options struct {
+	Log           loggers.Logger
+	CheckInterval time.Duration
+	MaxSize       int
+	MinMaxSize    int
+	Running       bool
+}
+
+// Options for a partition.
+type OptionsPartition struct {
+	// When to clear the this partition.
+	ClearWhen ClearWhen
+
+	// Weight is a number between 1 and 100 that indicates how, in general, how big this partition may get.
+	Weight int
+}
+
+func (o OptionsPartition) WeightFraction() float64 {
+	return float64(o.Weight) / 100
+}
+
+func (o OptionsPartition) CalculateMaxSize(maxSizePerPartition int) int {
+	return int(math.Floor(float64(maxSizePerPartition) * o.WeightFraction()))
+}
+
+// A dynamic partitioned cache.
+type Cache struct {
+	mu sync.RWMutex
+
+	partitions map[string]PartitionManager
+
+	onEvict           func(k, v any)
+	evictedIdentities *collections.Stack[identity.Identity]
+
+	opts  Options
+	infol logg.LevelLogger
+
+	stats    *stats
+	stopOnce sync.Once
+	stop     func()
+}
+
+// DrainEvictedIdentities drains the evicted identities from the cache.
+func (c *Cache) DrainEvictedIdentities() []identity.Identity {
+	return c.evictedIdentities.Drain()
+}
+
+// ClearMatching clears all partition for which the predicate returns true.
+func (c *Cache) ClearMatching(predicate func(k, v any) bool) {
+	g := rungroup.Run[PartitionManager](context.Background(), rungroup.Config[PartitionManager]{
+		NumWorkers: len(c.partitions),
+		Handle: func(ctx context.Context, partition PartitionManager) error {
+			partition.clearMatching(predicate)
+			return nil
+		},
+	})
+
+	for _, p := range c.partitions {
+		g.Enqueue(p)
+	}
+
+	g.Wait()
+}
+
+// ClearOnRebuild prepares the cache for a new rebuild taking the given changeset into account.
+func (c *Cache) ClearOnRebuild(changeset ...identity.Identity) {
+	g := rungroup.Run[PartitionManager](context.Background(), rungroup.Config[PartitionManager]{
+		NumWorkers: len(c.partitions),
+		Handle: func(ctx context.Context, partition PartitionManager) error {
+			partition.clearOnRebuild(changeset...)
+			return nil
+		},
+	})
+
+	for _, p := range c.partitions {
+		g.Enqueue(p)
+	}
+
+	g.Wait()
+
+	// Clear any entries marked as stale above.
+	g = rungroup.Run[PartitionManager](context.Background(), rungroup.Config[PartitionManager]{
+		NumWorkers: len(c.partitions),
+		Handle: func(ctx context.Context, partition PartitionManager) error {
+			partition.clearStale()
+			return nil
+		},
+	})
+
+	for _, p := range c.partitions {
+		g.Enqueue(p)
+	}
+
+	g.Wait()
+}
+
+type keysProvider interface {
+	Keys() []string
+}
+
+// Keys returns a list of keys in all partitions.
+func (c *Cache) Keys(predicate func(s string) bool) []string {
+	if predicate == nil {
+		predicate = func(s string) bool { return true }
+	}
+	var keys []string
+	for pn, g := range c.partitions {
+		pkeys := g.(keysProvider).Keys()
+		for _, k := range pkeys {
+			p := path.Join(pn, k)
+			if predicate(p) {
+				keys = append(keys, p)
+			}
+		}
+
+	}
+	return keys
+}
+
+func calculateMaxSizePerPartition(maxItemsTotal, totalWeightQuantity, numPartitions int) int {
+	if numPartitions == 0 {
+		panic("numPartitions must be > 0")
+	}
+	if totalWeightQuantity == 0 {
+		panic("totalWeightQuantity must be > 0")
+	}
+
+	avgWeight := float64(totalWeightQuantity) / float64(numPartitions)
+	return int(math.Floor(float64(maxItemsTotal) / float64(numPartitions) * (100.0 / avgWeight)))
+}
+
+// Stop stops the cache.
+func (c *Cache) Stop() {
+	c.stopOnce.Do(func() {
+		c.stop()
+	})
+}
+
+func (c *Cache) adjustCurrentMaxSize() {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+
+	if len(c.partitions) == 0 {
+		return
+	}
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	s := c.stats
+	s.memstatsCurrent = m
+	// fmt.Printf("\n\nAvailable = %v\nAlloc = %v\nTotalAlloc = %v\nSys = %v\nNumGC = %v\nMaxSize = %d\nAdjustmentFactor=%f\n\n", helpers.FormatByteCount(s.availableMemory), helpers.FormatByteCount(m.Alloc), helpers.FormatByteCount(m.TotalAlloc), helpers.FormatByteCount(m.Sys), m.NumGC, c.stats.currentMaxSize, s.adjustmentFactor)
+
+	if s.availableMemory >= s.memstatsCurrent.Alloc {
+		if s.adjustmentFactor <= 1.0 {
+			s.adjustmentFactor += 0.2
+		}
+	} else {
+		// We're low on memory.
+		s.adjustmentFactor -= 0.4
+	}
+
+	if s.adjustmentFactor <= 0 {
+		s.adjustmentFactor = 0.05
+	}
+
+	if !s.adjustCurrentMaxSize() {
+		return
+	}
+
+	totalWeight := 0
+	for _, pm := range c.partitions {
+		totalWeight += pm.getOptions().Weight
+	}
+
+	maxSizePerPartition := calculateMaxSizePerPartition(c.stats.currentMaxSize, totalWeight, len(c.partitions))
+
+	evicted := 0
+	for _, p := range c.partitions {
+		evicted += p.adjustMaxSize(p.getOptions().CalculateMaxSize(maxSizePerPartition))
+	}
+
+	if evicted > 0 {
+		c.infol.
+			WithFields(
+				logg.Fields{
+					{Name: "evicted", Value: evicted},
+					{Name: "numGC", Value: m.NumGC},
+					{Name: "limit", Value: helpers.FormatByteCount(c.stats.availableMemory)},
+					{Name: "alloc", Value: helpers.FormatByteCount(m.Alloc)},
+					{Name: "totalAlloc", Value: helpers.FormatByteCount(m.TotalAlloc)},
+				},
+			).Logf("adjusted partitions' max size")
+	}
+}
+
+func (c *Cache) start() func() {
+	ticker := time.NewTicker(c.opts.CheckInterval)
+	quit := make(chan struct{})
+
+	go func() {
+		for {
+			select {
+			case <-ticker.C:
+				c.adjustCurrentMaxSize()
+			case <-quit:
+				ticker.Stop()
+				return
+			}
+		}
+	}()
+
+	return func() {
+		close(quit)
+	}
+}
+
+var partitionNameRe = regexp.MustCompile(`^\/[a-zA-Z0-9]{4}(\/[a-zA-Z0-9]+)?(\/[a-zA-Z0-9]+)?`)
+
+// GetOrCreatePartition gets or creates a partition with the given name.
+func GetOrCreatePartition[K comparable, V any](c *Cache, name string, opts OptionsPartition) *Partition[K, V] {
+	if c == nil {
+		panic("nil Cache")
+	}
+	if opts.Weight < 1 || opts.Weight > 100 {
+		panic("invalid Weight, must be between 1 and 100")
+	}
+
+	if partitionNameRe.FindString(name) != name {
+		panic(fmt.Sprintf("invalid partition name %q", name))
+	}
+
+	c.mu.RLock()
+	p, found := c.partitions[name]
+	c.mu.RUnlock()
+	if found {
+		return p.(*Partition[K, V])
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	// Double check.
+	p, found = c.partitions[name]
+	if found {
+		return p.(*Partition[K, V])
+	}
+
+	// At this point, we don't know the the number of partitions or their configuration, but
+	// this will be re-adjusted later.
+	const numberOfPartitionsEstimate = 10
+	maxSize := opts.CalculateMaxSize(c.opts.MaxSize / numberOfPartitionsEstimate)
+
+	onEvict := func(k K, v V) {
+		c.onEvict(k, v)
+	}
+
+	// Create a new partition and cache it.
+	partition := &Partition[K, V]{
+		c:       lazycache.New(lazycache.Options[K, V]{MaxEntries: maxSize, OnEvict: onEvict}),
+		maxSize: maxSize,
+		trace:   c.opts.Log.Logger().WithLevel(logg.LevelTrace).WithField("partition", name),
+		opts:    opts,
+	}
+	c.partitions[name] = partition
+
+	return partition
+}
+
+// Partition is a partition in the cache.
+type Partition[K comparable, V any] struct {
+	c *lazycache.Cache[K, V]
+
+	zero V
+
+	trace logg.LevelLogger
+	opts  OptionsPartition
+
+	maxSize int
+}
+
+// GetOrCreate gets or creates a value for the given key.
+func (p *Partition[K, V]) GetOrCreate(key K, create func(key K) (V, error)) (V, error) {
+	v, _, err := p.c.GetOrCreate(key, create)
+	return v, err
+}
+
+// GetOrCreateWitTimeout gets or creates a value for the given key and times out if the create function
+// takes too long.
+func (p *Partition[K, V]) GetOrCreateWitTimeout(key K, duration time.Duration, create func(key K) (V, error)) (V, error) {
+	resultch := make(chan V, 1)
+	errch := make(chan error, 1)
+
+	go func() {
+		v, _, err := p.c.GetOrCreate(key, create)
+		if err != nil {
+			errch <- err
+			return
+		}
+		resultch <- v
+	}()
+
+	select {
+	case v := <-resultch:
+		return v, nil
+	case err := <-errch:
+		return p.zero, err
+	case <-time.After(duration):
+		return p.zero, &herrors.TimeoutError{
+			Duration: duration,
+		}
+	}
+}
+
+func (p *Partition[K, V]) clearMatching(predicate func(k, v any) bool) {
+	p.c.DeleteFunc(func(key K, v V) bool {
+		if predicate(key, v) {
+			p.trace.Log(
+				logg.StringFunc(
+					func() string {
+						return fmt.Sprintf("clearing cache key %v", key)
+					},
+				),
+			)
+			return true
+		}
+		return false
+	})
+}
+
+func (p *Partition[K, V]) clearOnRebuild(changeset ...identity.Identity) {
+	opts := p.getOptions()
+	if opts.ClearWhen == ClearNever {
+		return
+	}
+
+	if opts.ClearWhen == ClearOnRebuild {
+		// Clear all.
+		p.Clear()
+		return
+	}
+
+	depsFinder := identity.NewFinder(identity.FinderConfig{})
+
+	shouldDelete := func(key K, v V) bool {
+		// We always clear elements marked as stale.
+		if resource.IsStaleAny(v) {
+			return true
+		}
+
+		// Now check if this entry has changed based on the changeset
+		// based on filesystem events.
+		if len(changeset) == 0 {
+			// Nothing changed.
+			return false
+		}
+
+		var probablyDependent bool
+		identity.WalkIdentitiesShallow(v, func(level int, id2 identity.Identity) bool {
+			for _, id := range changeset {
+				if r := depsFinder.Contains(id, id2, -1); r > 0 {
+					// It's probably dependent, evict from cache.
+					probablyDependent = true
+					return true
+				}
+			}
+			return false
+		})
+
+		return probablyDependent
+	}
+
+	// First pass.
+	// Second pass needs to be done in a separate loop to catch any
+	// elements marked as stale in the other partitions.
+	p.c.DeleteFunc(func(key K, v V) bool {
+		if shouldDelete(key, v) {
+			p.trace.Log(
+				logg.StringFunc(
+					func() string {
+						return fmt.Sprintf("first pass: clearing cache key %v", key)
+					},
+				),
+			)
+			return true
+		}
+		return false
+	})
+}
+
+func (p *Partition[K, V]) Keys() []K {
+	var keys []K
+	p.c.DeleteFunc(func(key K, v V) bool {
+		keys = append(keys, key)
+		return false
+	})
+	return keys
+}
+
+func (p *Partition[K, V]) clearStale() {
+	p.c.DeleteFunc(func(key K, v V) bool {
+		isStale := resource.IsStaleAny(v)
+		if isStale {
+			p.trace.Log(
+				logg.StringFunc(
+					func() string {
+						return fmt.Sprintf("second pass: clearing cache key %v", key)
+					},
+				),
+			)
+		}
+
+		return isStale
+	})
+}
+
+// adjustMaxSize adjusts the max size of the and returns the number of items evicted.
+func (p *Partition[K, V]) adjustMaxSize(newMaxSize int) int {
+	if newMaxSize < minMaxSize {
+		newMaxSize = minMaxSize
+	}
+	oldMaxSize := p.maxSize
+	if newMaxSize == oldMaxSize {
+		return 0
+	}
+	p.maxSize = newMaxSize
+	// fmt.Println("Adjusting max size of partition from", oldMaxSize, "to", newMaxSize)
+	return p.c.Resize(newMaxSize)
+}
+
+func (p *Partition[K, V]) getMaxSize() int {
+	return p.maxSize
+}
+
+func (p *Partition[K, V]) getOptions() OptionsPartition {
+	return p.opts
+}
+
+func (p *Partition[K, V]) Clear() {
+	p.c.DeleteFunc(func(key K, v V) bool {
+		return true
+	})
+}
+
+func (p *Partition[K, V]) Get(ctx context.Context, key K) (V, bool) {
+	return p.c.Get(key)
+}
+
+type PartitionManager interface {
+	adjustMaxSize(addend int) int
+	getMaxSize() int
+	getOptions() OptionsPartition
+	clearOnRebuild(changeset ...identity.Identity)
+	clearMatching(predicate func(k, v any) bool)
+	clearStale()
+}
+
+const (
+	ClearOnRebuild ClearWhen = iota + 1
+	ClearOnChange
+	ClearNever
+)
+
+type ClearWhen int
+
+type stats struct {
+	opts            Options
+	memstatsCurrent runtime.MemStats
+	currentMaxSize  int
+	availableMemory uint64
+
+	adjustmentFactor float64
+}
+
+func (s *stats) adjustCurrentMaxSize() bool {
+	newCurrentMaxSize := int(math.Floor(float64(s.opts.MaxSize) * s.adjustmentFactor))
+
+	if newCurrentMaxSize < s.opts.MinMaxSize {
+		newCurrentMaxSize = int(s.opts.MinMaxSize)
+	}
+	changed := newCurrentMaxSize != s.currentMaxSize
+	s.currentMaxSize = newCurrentMaxSize
+	return changed
+}
+
+// CleanKey turns s into a format suitable for a cache key for this package.
+// The key will be a Unix-styled path with a leading slash but no trailing slash.
+func CleanKey(s string) string {
+	return path.Clean(paths.ToSlashPreserveLeading(s))
+}

cache/dynacache/dynacache_test.go

@@ -0,0 +1,175 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package dynacache
+
+import (
+	"path/filepath"
+	"testing"
+
+	qt "github.com/frankban/quicktest"
+	"github.com/gohugoio/hugo/common/loggers"
+	"github.com/gohugoio/hugo/identity"
+	"github.com/gohugoio/hugo/resources/resource"
+)
+
+var (
+	_ resource.StaleInfo = (*testItem)(nil)
+	_ identity.Identity  = (*testItem)(nil)
+)
+
+type testItem struct {
+	name    string
+	isStale bool
+}
+
+func (t testItem) IsStale() bool {
+	return t.isStale
+}
+
+func (t testItem) IdentifierBase() string {
+	return t.name
+}
+
+func TestCache(t *testing.T) {
+	t.Parallel()
+	c := qt.New(t)
+
+	cache := New(Options{
+		Log: loggers.NewDefault(),
+	})
+
+	c.Cleanup(func() {
+		cache.Stop()
+	})
+
+	opts := OptionsPartition{Weight: 30}
+
+	c.Assert(cache, qt.Not(qt.IsNil))
+
+	p1 := GetOrCreatePartition[string, testItem](cache, "/aaaa/bbbb", opts)
+	c.Assert(p1, qt.Not(qt.IsNil))
+
+	p2 := GetOrCreatePartition[string, testItem](cache, "/aaaa/bbbb", opts)
+
+	c.Assert(func() { GetOrCreatePartition[string, testItem](cache, "foo bar", opts) }, qt.PanicMatches, ".*invalid partition name.*")
+	c.Assert(func() { GetOrCreatePartition[string, testItem](cache, "/aaaa/cccc", OptionsPartition{Weight: 1234}) }, qt.PanicMatches, ".*invalid Weight.*")
+
+	c.Assert(p2, qt.Equals, p1)
+
+	p3 := GetOrCreatePartition[string, testItem](cache, "/aaaa/cccc", opts)
+	c.Assert(p3, qt.Not(qt.IsNil))
+	c.Assert(p3, qt.Not(qt.Equals), p1)
+
+	c.Assert(func() { New(Options{}) }, qt.PanicMatches, ".*nil Log.*")
+}
+
+func TestCalculateMaxSizePerPartition(t *testing.T) {
+	t.Parallel()
+	c := qt.New(t)
+
+	c.Assert(calculateMaxSizePerPartition(1000, 500, 5), qt.Equals, 200)
+	c.Assert(calculateMaxSizePerPartition(1000, 250, 5), qt.Equals, 400)
+	c.Assert(func() { calculateMaxSizePerPartition(1000, 250, 0) }, qt.PanicMatches, ".*must be > 0.*")
+	c.Assert(func() { calculateMaxSizePerPartition(1000, 0, 1) }, qt.PanicMatches, ".*must be > 0.*")
+}
+
+func TestCleanKey(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(CleanKey("a/b/c"), qt.Equals, "/a/b/c")
+	c.Assert(CleanKey("/a/b/c"), qt.Equals, "/a/b/c")
+	c.Assert(CleanKey("a/b/c/"), qt.Equals, "/a/b/c")
+	c.Assert(CleanKey(filepath.FromSlash("/a/b/c/")), qt.Equals, "/a/b/c")
+}
+
+func newTestCache(t *testing.T) *Cache {
+	cache := New(
+		Options{
+			Log: loggers.NewDefault(),
+		},
+	)
+
+	p1 := GetOrCreatePartition[string, testItem](cache, "/aaaa/bbbb", OptionsPartition{Weight: 30, ClearWhen: ClearOnRebuild})
+	p2 := GetOrCreatePartition[string, testItem](cache, "/aaaa/cccc", OptionsPartition{Weight: 30, ClearWhen: ClearOnChange})
+
+	p1.GetOrCreate("clearOnRebuild", func(string) (testItem, error) {
+		return testItem{}, nil
+	})
+
+	p2.GetOrCreate("clearBecauseStale", func(string) (testItem, error) {
+		return testItem{
+			isStale: true,
+		}, nil
+	})
+
+	p2.GetOrCreate("clearBecauseIdentityChanged", func(string) (testItem, error) {
+		return testItem{
+			name: "changed",
+		}, nil
+	})
+
+	p2.GetOrCreate("clearNever", func(string) (testItem, error) {
+		return testItem{
+			isStale: false,
+		}, nil
+	})
+
+	t.Cleanup(func() {
+		cache.Stop()
+	})
+
+	return cache
+}
+
+func TestClear(t *testing.T) {
+	t.Parallel()
+	c := qt.New(t)
+
+	predicateAll := func(string) bool {
+		return true
+	}
+
+	cache := newTestCache(t)
+
+	c.Assert(cache.Keys(predicateAll), qt.HasLen, 4)
+
+	cache.ClearOnRebuild()
+
+	// Stale items are always cleared.
+	c.Assert(cache.Keys(predicateAll), qt.HasLen, 2)
+
+	cache = newTestCache(t)
+	cache.ClearOnRebuild(identity.StringIdentity("changed"))
+
+	c.Assert(cache.Keys(nil), qt.HasLen, 1)
+
+	cache = newTestCache(t)
+
+	cache.ClearMatching(func(k, v any) bool {
+		return k.(string) == "clearOnRebuild"
+	})
+
+	c.Assert(cache.Keys(predicateAll), qt.HasLen, 3)
+
+	cache.adjustCurrentMaxSize()
+}
+
+func TestAdjustCurrentMaxSize(t *testing.T) {
+	t.Parallel()
+	c := qt.New(t)
+	cache := newTestCache(t)
+	alloc := cache.stats.memstatsCurrent.Alloc
+	cache.adjustCurrentMaxSize()
+	c.Assert(cache.stats.memstatsCurrent.Alloc, qt.Not(qt.Equals), alloc)
+}

cache/filecache/filecache.go

@@ -24,6 +24,7 @@ import (
 	"time"
 
 	"github.com/gohugoio/hugo/common/hugio"
+	"github.com/gohugoio/hugo/hugofs"
 
 	"github.com/gohugoio/hugo/helpers"
 
@@ -109,7 +110,7 @@ func (l *lockedFile) Close() error {
 func (c *Cache) init() error {
 	c.initOnce.Do(func() {
 		// Create the base dir if it does not exist.
-		if err := c.Fs.MkdirAll("", 0777); err != nil && !os.IsExist(err) {
+		if err := c.Fs.MkdirAll("", 0o777); err != nil && !os.IsExist(err) {
 			c.initErr = err
 		}
 	})
@@ -146,7 +147,8 @@ func (c *Cache) WriteCloser(id string) (ItemInfo, io.WriteCloser, error) {
 // it when done.
 func (c *Cache) ReadOrCreate(id string,
 	read func(info ItemInfo, r io.ReadSeeker) error,
-	create func(info ItemInfo, w io.WriteCloser) error) (info ItemInfo, err error) {
+	create func(info ItemInfo, w io.WriteCloser) error,
+) (info ItemInfo, err error) {
 	if err := c.init(); err != nil {
 		return ItemInfo{}, err
 	}
@@ -380,7 +382,7 @@ func NewCaches(p *helpers.PathSpec) (Caches, error) {
 
 		baseDir := v.DirCompiled
 
-		bfs := afero.NewBasePathFs(cfs, baseDir)
+		bfs := hugofs.NewBasePathFs(cfs, baseDir)
 
 		var pruneAllRootDir string
 		if k == CacheKeyModules {

cache/filecache/filecache_config.go

@@ -15,6 +15,7 @@
 package filecache
 
 import (
+	"errors"
 	"fmt"
 	"path"
 	"path/filepath"
@@ -24,8 +25,6 @@ import (
 	"github.com/gohugoio/hugo/common/maps"
 	"github.com/gohugoio/hugo/config"
 
-	"errors"
-
 	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/afero"
 )
@@ -225,7 +224,6 @@ func DecodeConfig(fs afero.Fs, bcfg config.BaseConfig, m map[string]any) (Config
 
 // Resolves :resourceDir => /myproject/resources etc., :cacheDir => ...
 func resolveDirPlaceholder(fs afero.Fs, bcfg config.BaseConfig, placeholder string) (cacheDir string, isResource bool, err error) {
-
 	switch strings.ToLower(placeholder) {
 	case ":resourcedir":
 		return "", true, nil

cache/filecache/filecache_integration_test.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,7 +15,6 @@ package filecache_test
 
 import (
 	"path/filepath"
-
 	"testing"
 	"time"
 
@@ -47,7 +46,6 @@ title: "Home"
 	_, err := b.H.BaseFs.ResourcesCache.Stat(filepath.Join("_gen", "images"))
 
 	b.Assert(err, qt.IsNil)
-
 }
 
 func TestPruneImages(t *testing.T) {
@@ -55,6 +53,7 @@ func TestPruneImages(t *testing.T) {
 		// TODO(bep)
 		t.Skip("skip flaky test on CI server")
 	}
+	t.Skip("skip flaky test")
 	files := `
 -- hugo.toml --
 baseURL = "https://example.com"
@@ -92,7 +91,7 @@ iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNkYPhfDwAChwGA60e6kgAA
 
 	// TODO(bep) we need a way to test full rebuilds.
 	// For now, just sleep a little so the cache elements expires.
-	time.Sleep(300 * time.Millisecond)
+	time.Sleep(500 * time.Millisecond)
 
 	b.RenameFile("assets/a/pixel.png", "assets/b/pixel2.png").Build()
 
@@ -104,5 +103,4 @@ iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNkYPhfDwAChwGA60e6kgAA
 	b.Assert(err, qt.Not(qt.IsNil))
 	_, err = b.H.BaseFs.ResourcesCache.Stat(imagesCacheDir)
 	b.Assert(err, qt.IsNil)
-
 }

cache/filecache/filecache_pruner.go

@@ -60,7 +60,6 @@ func (c *Cache) Prune(force bool) (int, error) {
 	counter := 0
 
 	err := afero.Walk(c.Fs, "", func(name string, info os.FileInfo, err error) error {
-
 		if info == nil {
 			return nil
 		}
@@ -69,7 +68,6 @@ func (c *Cache) Prune(force bool) (int, error) {
 
 		if info.IsDir() {
 			f, err := c.Fs.Open(name)
-
 			if err != nil {
 				// This cache dir may not exist.
 				return nil

cache/filecache/filecache_test.go

@@ -1,4 +1,4 @@
-// Copyright 2018 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -17,7 +17,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"path/filepath"
 	"strings"
 	"sync"
 	"testing"
@@ -86,17 +85,8 @@ dir = ":cacheDir/c"
 		cache := caches.Get("GetJSON")
 		c.Assert(cache, qt.Not(qt.IsNil))
 
-		bfs, ok := cache.Fs.(*afero.BasePathFs)
-		c.Assert(ok, qt.Equals, true)
-		filename, err := bfs.RealPath("key")
-		c.Assert(err, qt.IsNil)
-
 		cache = caches.Get("Images")
 		c.Assert(cache, qt.Not(qt.IsNil))
-		bfs, ok = cache.Fs.(*afero.BasePathFs)
-		c.Assert(ok, qt.Equals, true)
-		filename, _ = bfs.RealPath("key")
-		c.Assert(filename, qt.Equals, filepath.FromSlash("_gen/images/key"))
 
 		rf := func(s string) func() (io.ReadCloser, error) {
 			return func() (io.ReadCloser, error) {

cache/namedmemcache/named_cache.go

@@ -1,78 +0,0 @@
-// Copyright 2018 The Hugo Authors. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package namedmemcache provides a memory cache with a named lock. This is suitable
-// for situations where creating the cached resource can be time consuming or otherwise
-// resource hungry, or in situations where a "once only per key" is a requirement.
-package namedmemcache
-
-import (
-	"sync"
-
-	"github.com/BurntSushi/locker"
-)
-
-// Cache holds the cached values.
-type Cache struct {
-	nlocker *locker.Locker
-	cache   map[string]cacheEntry
-	mu      sync.RWMutex
-}
-
-type cacheEntry struct {
-	value any
-	err   error
-}
-
-// New creates a new cache.
-func New() *Cache {
-	return &Cache{
-		nlocker: locker.NewLocker(),
-		cache:   make(map[string]cacheEntry),
-	}
-}
-
-// Clear clears the cache state.
-func (c *Cache) Clear() {
-	c.mu.Lock()
-	defer c.mu.Unlock()
-
-	c.cache = make(map[string]cacheEntry)
-	c.nlocker = locker.NewLocker()
-}
-
-// GetOrCreate tries to get the value with the given cache key, if not found
-// create will be called and cached.
-// This method is thread safe. It also guarantees that the create func for a given
-// key is invoked only once for this cache.
-func (c *Cache) GetOrCreate(key string, create func() (any, error)) (any, error) {
-	c.mu.RLock()
-	entry, found := c.cache[key]
-	c.mu.RUnlock()
-
-	if found {
-		return entry.value, entry.err
-	}
-
-	c.nlocker.Lock(key)
-	defer c.nlocker.Unlock(key)
-
-	// Create it.
-	value, err := create()
-
-	c.mu.Lock()
-	c.cache[key] = cacheEntry{value: value, err: err}
-	c.mu.Unlock()
-
-	return value, err
-}

cache/namedmemcache/named_cache_test.go

@@ -1,80 +0,0 @@
-// Copyright 2018 The Hugo Authors. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package namedmemcache
-
-import (
-	"fmt"
-	"sync"
-	"testing"
-
-	qt "github.com/frankban/quicktest"
-)
-
-func TestNamedCache(t *testing.T) {
-	t.Parallel()
-	c := qt.New(t)
-
-	cache := New()
-
-	counter := 0
-	create := func() (any, error) {
-		counter++
-		return counter, nil
-	}
-
-	for i := 0; i < 5; i++ {
-		v1, err := cache.GetOrCreate("a1", create)
-		c.Assert(err, qt.IsNil)
-		c.Assert(v1, qt.Equals, 1)
-		v2, err := cache.GetOrCreate("a2", create)
-		c.Assert(err, qt.IsNil)
-		c.Assert(v2, qt.Equals, 2)
-	}
-
-	cache.Clear()
-
-	v3, err := cache.GetOrCreate("a2", create)
-	c.Assert(err, qt.IsNil)
-	c.Assert(v3, qt.Equals, 3)
-}
-
-func TestNamedCacheConcurrent(t *testing.T) {
-	t.Parallel()
-
-	c := qt.New(t)
-
-	var wg sync.WaitGroup
-
-	cache := New()
-
-	create := func(i int) func() (any, error) {
-		return func() (any, error) {
-			return i, nil
-		}
-	}
-
-	for i := 0; i < 10; i++ {
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
-			for j := 0; j < 100; j++ {
-				id := fmt.Sprintf("id%d", j)
-				v, err := cache.GetOrCreate(id, create(j))
-				c.Assert(err, qt.IsNil)
-				c.Assert(v, qt.Equals, j)
-			}
-		}()
-	}
-	wg.Wait()
-}

check_gofmt.sh

@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+diff <(gofmt -d .) <(printf '')

codegen/methods.go

@@ -461,7 +461,6 @@ func collectMethodsRecursive(pkg string, f []*ast.Field) []string {
 						pkg,
 						tt.Methods.List)...)
 			}
-
 		} else {
 			// Embedded, but in a different file/package. Return the
 			// package.Name and deal with that later.

commands/commandeer.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -22,6 +22,7 @@ import (
 	"os"
 	"os/signal"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -38,6 +39,7 @@ import (
 
 	"github.com/gohugoio/hugo/common/hstrings"
 	"github.com/gohugoio/hugo/common/htime"
+	"github.com/gohugoio/hugo/common/hugo"
 	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/common/paths"
 	"github.com/gohugoio/hugo/config"
@@ -50,9 +52,7 @@ import (
 	"github.com/spf13/cobra"
 )
 
-var (
-	errHelp = errors.New("help requested")
-)
+var errHelp = errors.New("help requested")
 
 // Execute executes a command.
 func Execute(args []string) error {
@@ -182,11 +182,9 @@ func (r *rootCommand) ConfigFromConfig(key int32, oldConf *commonConfig) (*commo
 			cfg:     oldConf.cfg,
 			fs:      fs,
 		}, nil
-
 	})
 
 	return cc, err
-
 }
 
 func (r *rootCommand) ConfigFromProvider(key int32, cfg config.Provider) (*commonConfig, error) {
@@ -205,13 +203,10 @@ func (r *rootCommand) ConfigFromProvider(key int32, cfg config.Provider) (*commo
 			cfg = config.New()
 		}
 
-		if !cfg.IsSet("renderToDisk") {
-			cfg.Set("renderToDisk", true)
-		}
 		if !cfg.IsSet("workingDir") {
 			cfg.Set("workingDir", dir)
 		} else {
-			if err := os.MkdirAll(cfg.GetString("workingDir"), 0777); err != nil {
+			if err := os.MkdirAll(cfg.GetString("workingDir"), 0o777); err != nil {
 				return nil, fmt.Errorf("failed to create workingDir: %w", err)
 			}
 		}
@@ -241,9 +236,7 @@ func (r *rootCommand) ConfigFromProvider(key int32, cfg config.Provider) (*commo
 
 		sourceFs := hugofs.Os
 		var destinationFs afero.Fs
-		if cfg.GetBool("renderToDisk") {
-			destinationFs = hugofs.Os
-		} else {
+		if cfg.GetBool("renderToMemory") {
 			destinationFs = afero.NewMemMapFs()
 			if renderStaticToDisk {
 				// Hybrid, render dynamic content to Root.
@@ -253,6 +246,8 @@ func (r *rootCommand) ConfigFromProvider(key int32, cfg config.Provider) (*commo
 				cfg.Set("publishDirDynamic", "/")
 				cfg.Set("publishDirStatic", "/")
 			}
+		} else {
+			destinationFs = hugofs.Os
 		}
 
 		fs := hugofs.NewFromSourceAndDestination(sourceFs, destinationFs, cfg)
@@ -262,7 +257,7 @@ func (r *rootCommand) ConfigFromProvider(key int32, cfg config.Provider) (*commo
 			publishDirStatic := cfg.GetString("publishDirStatic")
 			workingDir := cfg.GetString("workingDir")
 			absPublishDirStatic := paths.AbsPathify(workingDir, publishDirStatic)
-			staticFs := afero.NewBasePathFs(afero.NewOsFs(), absPublishDirStatic)
+			staticFs := hugofs.NewBasePathFs(afero.NewOsFs(), absPublishDirStatic)
 
 			// Serve from both the static and dynamic fs,
 			// the first will take priority.
@@ -303,7 +298,6 @@ func (r *rootCommand) ConfigFromProvider(key int32, cfg config.Provider) (*commo
 	})
 
 	return cc, err
-
 }
 
 func (r *rootCommand) HugFromConfig(conf *commonConfig) (*hugolib.HugoSites, error) {
@@ -346,9 +340,11 @@ func (r *rootCommand) Run(ctx context.Context, cd *simplecobra.Commandeer, args
 			defer r.timeTrack(time.Now(), "Built")
 		}
 		err := b.build()
-		return err
+		if err != nil {
+			return err
+		}
+		return nil
 	}()
-
 	if err != nil {
 		return err
 	}
@@ -410,8 +406,15 @@ func (r *rootCommand) PreRun(cd, runner *simplecobra.Commandeer) error {
 		return err
 	}
 
-	r.commonConfigs = lazycache.New[int32, *commonConfig](lazycache.Options{MaxEntries: 5})
-	r.hugoSites = lazycache.New[int32, *hugolib.HugoSites](lazycache.Options{MaxEntries: 5})
+	r.commonConfigs = lazycache.New(lazycache.Options[int32, *commonConfig]{MaxEntries: 5})
+	// We don't want to keep stale HugoSites in memory longer than needed.
+	r.hugoSites = lazycache.New(lazycache.Options[int32, *hugolib.HugoSites]{
+		MaxEntries: 1,
+		OnEvict: func(key int32, value *hugolib.HugoSites) {
+			value.Close()
+			runtime.GC()
+		},
+	})
 
 	return nil
 }
@@ -434,26 +437,26 @@ func (r *rootCommand) createLogger(running bool) (loggers.Logger, error) {
 		}
 	} else {
 		if r.verbose {
-			helpers.Deprecated("--verbose", "use --logLevel info", false)
+			hugo.Deprecate("--verbose", "use --logLevel info", "v0.114.0")
+			hugo.Deprecate("--verbose", "use --logLevel info", "v0.114.0")
 			level = logg.LevelInfo
 		}
 
 		if r.debug {
-			helpers.Deprecated("--debug", "use --logLevel debug", false)
+			hugo.Deprecate("--debug", "use --logLevel debug", "v0.114.0")
 			level = logg.LevelDebug
 		}
 	}
 
 	optsLogger := loggers.Options{
-		Distinct:    true,
-		Level:       level,
-		Stdout:      r.Out,
-		Stderr:      r.Out,
-		StoreErrors: running,
+		DistinctLevel: logg.LevelWarn,
+		Level:         level,
+		Stdout:        r.Out,
+		Stderr:        r.Out,
+		StoreErrors:   running,
 	}
 
 	return loggers.New(optsLogger), nil
-
 }
 
 func (r *rootCommand) Reset() {
@@ -491,6 +494,7 @@ Complete documentation is available at https://gohugo.io/.`
 	cmd.PersistentFlags().StringVar(&r.cfgFile, "config", "", "config file (default is hugo.yaml|json|toml)")
 	cmd.PersistentFlags().StringVar(&r.cfgDir, "configDir", "config", "config dir")
 	cmd.PersistentFlags().BoolVar(&r.quiet, "quiet", false, "build in quiet mode")
+	cmd.PersistentFlags().BoolVar(&r.renderToMemory, "renderToMemory", false, "render to memory (mostly useful when running the server)")
 
 	// Set bash-completion
 	_ = cmd.PersistentFlags().SetAnnotation("config", cobra.BashCompFilenameExt, config.ValidConfigFileExtensions)
@@ -499,7 +503,6 @@ Complete documentation is available at https://gohugo.io/.`
 	cmd.PersistentFlags().BoolVarP(&r.debug, "debug", "", false, "debug output")
 	cmd.PersistentFlags().StringVar(&r.logLevel, "logLevel", "", "log level (debug|info|warn|error)")
 	cmd.Flags().BoolVarP(&r.buildWatch, "watch", "w", false, "watch filesystem for changes and recreate as needed")
-	cmd.Flags().BoolVar(&r.renderToMemory, "renderToMemory", false, "render to memory (only useful for benchmark testing)")
 
 	// Configure local flags
 	applyLocalFlagsBuild(cmd, r)
@@ -519,7 +522,6 @@ func applyLocalFlagsBuildConfig(cmd *cobra.Command, r *rootCommand) {
 	_ = cmd.Flags().SetAnnotation("cacheDir", cobra.BashCompSubdirsInDir, []string{})
 	cmd.Flags().StringP("contentDir", "c", "", "filesystem path to content directory")
 	_ = cmd.Flags().SetAnnotation("theme", cobra.BashCompSubdirsInDir, []string{"themes"})
-
 }
 
 // Flags needed to do a build (used by hugo and hugo server commands)
@@ -558,7 +560,6 @@ func applyLocalFlagsBuild(cmd *cobra.Command, r *rootCommand) {
 	cmd.Flags().StringSlice("disableKinds", []string{}, "disable different kind of pages (home, RSS etc.)")
 	cmd.Flags().Bool("minify", false, "minify any supported output format (HTML, XML etc.)")
 	_ = cmd.Flags().SetAnnotation("destination", cobra.BashCompSubdirsInDir, []string{})
-
 }
 
 func (r *rootCommand) timeTrack(start time.Time, name string) {

commands/commands.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -37,5 +37,4 @@ func newExec() (*simplecobra.Exec, error) {
 	}
 
 	return simplecobra.New(rootCmd)
-
 }

commands/config.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -37,7 +37,6 @@ func newConfigCommand() *configCommand {
 			&configMountsCommand{},
 		},
 	}
-
 }
 
 type configCommand struct {
@@ -190,7 +189,6 @@ func (m *configModMounts) MarshalJSON() ([]byte, error) {
 		Dir:     m.m.Dir(),
 		Mounts:  mounts,
 	})
-
 }
 
 type configMountsCommand struct {

commands/convert.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -134,7 +134,7 @@ func (c *convertCommand) convertAndSavePage(p page.Page, site *hugolib.Site, tar
 		}
 	}
 
-	if p.File().IsZero() {
+	if p.File() == nil {
 		// No content file.
 		return nil
 	}
@@ -209,7 +209,7 @@ func (c *convertCommand) convertContents(format metadecoders.Format) error {
 
 	var pagesBackedByFile page.Pages
 	for _, p := range site.AllPages() {
-		if p.File().IsZero() {
+		if p.File() == nil {
 			continue
 		}
 		pagesBackedByFile = append(pagesBackedByFile, p)

commands/deploy.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -14,7 +14,7 @@
 //go:build !nodeploy
 // +build !nodeploy
 
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -38,7 +38,6 @@ import (
 )
 
 func newDeployCommand() simplecobra.Commander {
-
 	return &simpleCommand{
 		name:  "deploy",
 		short: "Deploy your site to a Cloud provider.",

commands/deploy_off.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -14,7 +14,7 @@
 //go:build nodeploy
 // +build nodeploy
 
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

commands/env.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

commands/gen.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -101,7 +101,7 @@ See https://xyproto.github.io/splash/docs/all.html for a preview of the availabl
 				}
 				if found, _ := helpers.Exists(genmandir, hugofs.Os); !found {
 					r.Println("Directory", genmandir, "does not exist, creating...")
-					if err := hugofs.Os.MkdirAll(genmandir, 0777); err != nil {
+					if err := hugofs.Os.MkdirAll(genmandir, 0o777); err != nil {
 						return err
 					}
 				}
@@ -150,7 +150,7 @@ url: %s
 				}
 				if found, _ := helpers.Exists(gendocdir, hugofs.Os); !found {
 					r.Println("Directory", gendocdir, "does not exist, creating...")
-					if err := hugofs.Os.MkdirAll(gendocdir, 0777); err != nil {
+					if err := hugofs.Os.MkdirAll(gendocdir, 0o777); err != nil {
 						return err
 					}
 				}
@@ -177,7 +177,6 @@ url: %s
 				cmd.PersistentFlags().SetAnnotation("dir", cobra.BashCompSubdirsInDir, []string{})
 			},
 		}
-
 	}
 
 	var docsHelperTarget string
@@ -196,7 +195,7 @@ url: %s
 				configProvider := func() docshelper.DocProvider {
 					conf := hugolib.DefaultConfig()
 					conf.CacheDir = "" // The default value does not make sense in the docs.
-					defaultConfig := parser.LowerCaseCamelJSONMarshaller{Value: conf}
+					defaultConfig := parser.NullBoolJSONMarshaller{Wrapped: parser.LowerCaseCamelJSONMarshaller{Value: conf}}
 					return docshelper.DocProvider{"config": defaultConfig}
 				}
 
@@ -241,7 +240,6 @@ url: %s
 			newDocsHelper(),
 		},
 	}
-
 }
 
 type genCommand struct {

commands/helpers.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -110,12 +110,11 @@ func flagsToCfgWithAdditionalConfigBase(cd *simplecobra.Commandeer, cfg config.P
 	})
 
 	return cfg
-
 }
 
 func mkdir(x ...string) {
 	p := filepath.Join(x...)
-	err := os.MkdirAll(p, 0777) // before umask
+	err := os.MkdirAll(p, 0o777) // before umask
 	if err != nil {
 		log.Fatal(err)
 	}

commands/hugo_windows.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -25,9 +25,9 @@ func init() {
 	// This message to show to Windows users if Hugo is opened from explorer.exe
 	cobra.MousetrapHelpText = `
 
-  Hugo is a command-line tool for generating static website.
+  Hugo is a command-line tool for generating static websites.
+
+  You need to open PowerShell and run Hugo from there.
 
-  You need to open cmd.exe and run Hugo from there.
-  
   Visit https://gohugo.io/ for more information.`
 }

commands/hugobuilder.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -24,6 +24,7 @@ import (
 	"runtime/trace"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/bep/logg"
@@ -34,6 +35,7 @@ import (
 	"github.com/gohugoio/hugo/common/hugo"
 	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/common/maps"
+	"github.com/gohugoio/hugo/common/paths"
 	"github.com/gohugoio/hugo/common/terminal"
 	"github.com/gohugoio/hugo/common/types"
 	"github.com/gohugoio/hugo/config"
@@ -83,7 +85,6 @@ func (c *hugoBuilder) withConf(fn func(conf *commonConfig)) {
 	c.confmu.Lock()
 	defer c.confmu.Unlock()
 	fn(c.conf)
-
 }
 
 type hugoBuilderErrState struct {
@@ -135,46 +136,12 @@ func (c *hugoBuilder) errCount() int {
 
 // getDirList provides NewWatcher() with a list of directories to watch for changes.
 func (c *hugoBuilder) getDirList() ([]string, error) {
-	var filenames []string
-
-	walkFn := func(path string, fi hugofs.FileMetaInfo, err error) error {
-		if err != nil {
-			c.r.logger.Errorln("walker: ", err)
-			return nil
-		}
-
-		if fi.IsDir() {
-			if fi.Name() == ".git" ||
-				fi.Name() == "node_modules" || fi.Name() == "bower_components" {
-				return filepath.SkipDir
-			}
-
-			filenames = append(filenames, fi.Meta().Filename)
-		}
-
-		return nil
-	}
-
 	h, err := c.hugo()
 	if err != nil {
 		return nil, err
 	}
-	watchFiles := h.PathSpec.BaseFs.WatchDirs()
-	for _, fi := range watchFiles {
-		if !fi.IsDir() {
-			filenames = append(filenames, fi.Meta().Filename)
-			continue
-		}
 
-		w := hugofs.NewWalkway(hugofs.WalkwayConfig{Logger: c.r.logger, Info: fi, WalkFn: walkFn})
-		if err := w.Walk(); err != nil {
-			c.r.logger.Errorln("walker: ", err)
-		}
-	}
-
-	filenames = helpers.UniqueStringsSorted(filenames)
-
-	return filenames, nil
+	return helpers.UniqueStringsSorted(h.PathSpec.BaseFs.WatchFilenames()), nil
 }
 
 func (c *hugoBuilder) initCPUProfile() (func(), error) {
@@ -441,7 +408,7 @@ func (c *hugoBuilder) copyStatic() (map[string]uint64, error) {
 }
 
 func (c *hugoBuilder) copyStaticTo(sourceFs *filesystems.SourceFilesystem) (uint64, error) {
-	infol := c.r.logger.InfoCommand("copy static")
+	infol := c.r.logger.InfoCommand("static")
 	publishDir := helpers.FilePathSeparator
 
 	if sourceFs.PublishFolder != "" {
@@ -467,11 +434,11 @@ func (c *hugoBuilder) copyStaticTo(sourceFs *filesystems.SourceFilesystem) (uint
 	if syncer.Delete {
 		infol.Logf("removing all files from destination that don't exist in static dirs")
 
-		syncer.DeleteFilter = func(f os.FileInfo) bool {
+		syncer.DeleteFilter = func(f fsync.FileInfo) bool {
 			return f.IsDir() && strings.HasPrefix(f.Name(), ".")
 		}
 	}
-	infol.Logf("syncing static files to %s", publishDir)
+	start := time.Now()
 
 	// because we are using a baseFs (to get the union right).
 	// set sync src to root
@@ -479,9 +446,10 @@ func (c *hugoBuilder) copyStaticTo(sourceFs *filesystems.SourceFilesystem) (uint
 	if err != nil {
 		return 0, err
 	}
+	loggers.TimeTrackf(infol, start, nil, "syncing static files to %s", publishDir)
 
-	// Sync runs Stat 3 times for every source file (which sounds much)
-	numFiles := fs.statCounter / 3
+	// Sync runs Stat 2 times for every source file.
+	numFiles := fs.statCounter / 2
 
 	return numFiles, err
 }
@@ -652,13 +620,31 @@ func (c *hugoBuilder) handleBuildErr(err error, msg string) {
 func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 	staticSyncer *staticSyncer,
 	evs []fsnotify.Event,
-	configSet map[string]bool) {
+	configSet map[string]bool,
+) {
 	defer func() {
 		c.errState.setWasErr(false)
 	}()
 
 	var isHandled bool
 
+	// Filter out ghost events (from deleted, renamed directories).
+	// This seems to be a bug in fsnotify, or possibly MacOS.
+	var n int
+	for _, ev := range evs {
+		keep := true
+		if ev.Has(fsnotify.Create) || ev.Has(fsnotify.Write) {
+			if _, err := os.Stat(ev.Name); err != nil {
+				keep = false
+			}
+		}
+		if keep {
+			evs[n] = ev
+			n++
+		}
+	}
+	evs = evs[:n]
+
 	for _, ev := range evs {
 		isConfig := configSet[ev.Name]
 		configChangeType := configChangeConfig
@@ -726,48 +712,25 @@ func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 		return
 	}
 
-	c.r.logger.Infoln("Received System Events:", evs)
+	c.r.logger.Debugln("Received System Events:", evs)
 
 	staticEvents := []fsnotify.Event{}
 	dynamicEvents := []fsnotify.Event{}
 
-	filtered := []fsnotify.Event{}
 	h, err := c.hugo()
 	if err != nil {
 		c.r.logger.Errorln("Error getting the Hugo object:", err)
 		return
 	}
+	n = 0
 	for _, ev := range evs {
 		if h.ShouldSkipFileChangeEvent(ev) {
 			continue
 		}
-		// Check the most specific first, i.e. files.
-		contentMapped := h.ContentChanges.GetSymbolicLinkMappings(ev.Name)
-		if len(contentMapped) > 0 {
-			for _, mapped := range contentMapped {
-				filtered = append(filtered, fsnotify.Event{Name: mapped, Op: ev.Op})
-			}
-			continue
-		}
-
-		// Check for any symbolic directory mapping.
-
-		dir, name := filepath.Split(ev.Name)
-
-		contentMapped = h.ContentChanges.GetSymbolicLinkMappings(dir)
-
-		if len(contentMapped) == 0 {
-			filtered = append(filtered, ev)
-			continue
-		}
-
-		for _, mapped := range contentMapped {
-			mappedFilename := filepath.Join(mapped, name)
-			filtered = append(filtered, fsnotify.Event{Name: mappedFilename, Op: ev.Op})
-		}
+		evs[n] = ev
+		n++
 	}
-
-	evs = filtered
+	evs = evs[:n]
 
 	for _, ev := range evs {
 		ext := filepath.Ext(ev.Name)
@@ -788,6 +751,7 @@ func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 		if istemp {
 			continue
 		}
+
 		if h.Deps.SourceSpec.IgnoreFile(ev.Name) {
 			continue
 		}
@@ -811,7 +775,7 @@ func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 			continue
 		}
 
-		walkAdder := func(path string, f hugofs.FileMetaInfo, err error) error {
+		walkAdder := func(path string, f hugofs.FileMetaInfo) error {
 			if f.IsDir() {
 				c.r.logger.Println("adding created directory to watchlist", path)
 				if err := watcher.Add(path); err != nil {
@@ -827,11 +791,10 @@ func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 		}
 
 		// recursively add new directories to watch list
-		// When mkdir -p is used, only the top directory triggers an event (at least on OSX)
-		if ev.Op&fsnotify.Create == fsnotify.Create {
+		if ev.Has(fsnotify.Create) || ev.Has(fsnotify.Rename) {
 			c.withConf(func(conf *commonConfig) {
 				if s, err := conf.fs.Source.Stat(ev.Name); err == nil && s.Mode().IsDir() {
-					_ = helpers.SymbolicWalk(conf.fs.Source, ev.Name, walkAdder)
+					_ = helpers.Walk(conf.fs.Source, ev.Name, walkAdder)
 				}
 			})
 		}
@@ -872,7 +835,7 @@ func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 					return
 				}
 				path := h.BaseFs.SourceFilesystems.MakeStaticPathRelative(ev.Name)
-				path = h.RelURL(helpers.ToSlashTrimLeading(path), false)
+				path = h.RelURL(paths.ToSlashTrimLeading(path), false)
 
 				livereload.RefreshPath(path)
 			} else {
@@ -909,7 +872,7 @@ func (c *hugoBuilder) handleEvents(watcher *watcher.Batcher,
 					// Nothing has changed.
 					return
 				} else if len(changed) == 1 {
-					pathToRefresh := h.PathSpec.RelURL(helpers.ToSlashTrimLeading(changed[0]), false)
+					pathToRefresh := h.PathSpec.RelURL(paths.ToSlashTrimLeading(changed[0]), false)
 					livereload.RefreshPath(pathToRefresh)
 				} else {
 					livereload.ForceRefresh()
@@ -944,7 +907,6 @@ func (c *hugoBuilder) hugo() (*hugolib.HugoSites, error) {
 		var err error
 		h, err = c.r.HugFromConfig(conf)
 		return err
-
 	}); err != nil {
 		return nil, err
 	}
@@ -968,7 +930,7 @@ func (c *hugoBuilder) hugoTry() *hugolib.HugoSites {
 
 func (c *hugoBuilder) loadConfig(cd *simplecobra.Commandeer, running bool) error {
 	cfg := config.New()
-	cfg.Set("renderToDisk", (c.s == nil && !c.r.renderToMemory) || (c.s != nil && c.s.renderToDisk))
+	cfg.Set("renderToMemory", c.r.renderToMemory)
 	watch := c.r.buildWatch || (c.s != nil && c.s.serverWatch)
 	if c.r.environment == "" {
 		// We need to set the environment as early as possible because we need it to load the correct config.
@@ -989,9 +951,10 @@ func (c *hugoBuilder) loadConfig(cd *simplecobra.Commandeer, running bool) error
 	cfg.Set("environment", c.r.environment)
 
 	cfg.Set("internal", maps.Params{
-		"running": running,
-		"watch":   watch,
-		"verbose": c.r.isVerbose(),
+		"running":        running,
+		"watch":          watch,
+		"verbose":        c.r.isVerbose(),
+		"fastRenderMode": c.fastRenderMode,
 	})
 
 	conf, err := c.r.ConfigFromProvider(c.r.configVersionID.Load(), flagsToCfg(cd, cfg))
@@ -1000,6 +963,7 @@ func (c *hugoBuilder) loadConfig(cd *simplecobra.Commandeer, running bool) error
 	}
 
 	if len(conf.configs.LoadingInfo.ConfigFiles) == 0 {
+		//lint:ignore ST1005 end user message.
 		return errors.New("Unable to locate config file or config directory. Perhaps you need to create a new site.\nRun `hugo help new` for details.")
 	}
 
@@ -1011,15 +975,16 @@ func (c *hugoBuilder) loadConfig(cd *simplecobra.Commandeer, running bool) error
 	}
 
 	return nil
-
 }
 
+var rebuildCounter atomic.Uint64
+
 func (c *hugoBuilder) printChangeDetected(typ string) {
 	msg := "\nChange"
 	if typ != "" {
 		msg += " of " + typ
 	}
-	msg += " detected, rebuilding site."
+	msg += fmt.Sprintf(" detected, rebuilding site (#%d).", rebuildCounter.Add(1))
 
 	c.r.logger.Println(msg)
 	const layout = "2006-01-02 15:04:05.000 -0700"
@@ -1034,25 +999,12 @@ func (c *hugoBuilder) rebuildSites(events []fsnotify.Event) error {
 		}
 	}
 	c.errState.setBuildErr(nil)
-	visited := c.visitedURLs.PeekAllSet()
 	h, err := c.hugo()
 	if err != nil {
 		return err
 	}
-	if c.fastRenderMode {
-		c.withConf(func(conf *commonConfig) {
-			// Make sure we always render the home pages
-			for _, l := range conf.configs.ConfigLangs() {
-				langPath := l.LanguagePrefix()
-				if langPath != "" {
-					langPath = langPath + "/"
-				}
-				home := h.PrependBasePath("/"+langPath, false)
-				visited[home] = true
-			}
-		})
-	}
-	return h.Build(hugolib.BuildCfg{NoBuildLock: true, RecentlyVisited: visited, ErrRecovery: c.errState.wasErr()}, events...)
+
+	return h.Build(hugolib.BuildCfg{NoBuildLock: true, RecentlyVisited: c.visitedURLs, ErrRecovery: c.errState.wasErr()}, events...)
 }
 
 func (c *hugoBuilder) reloadConfig() error {

commands/import.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -23,7 +23,6 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
-
 	"strconv"
 	"strings"
 	"time"
@@ -66,7 +65,6 @@ Import from Jekyll requires two paths, e.g. ` + "`hugo import jekyll jekyll_root
 	}
 
 	return c
-
 }
 
 type importCommand struct {
@@ -312,7 +310,7 @@ func (c *importCommand) convertJekyllPost(path, relPath, targetDir string, draft
 
 	targetFile := filepath.Join(targetDir, relPath)
 	targetParentDir := filepath.Dir(targetFile)
-	os.MkdirAll(targetParentDir, 0777)
+	os.MkdirAll(targetParentDir, 0o777)
 
 	contentBytes, err := os.ReadFile(path)
 	if err != nil {
@@ -398,7 +396,6 @@ func (c *importCommand) copyJekyllFilesAndFolders(jekyllRoot, dest string, jekyl
 }
 
 func (c *importCommand) importFromJekyll(args []string) error {
-
 	jekyllRoot, err := filepath.Abs(filepath.Clean(args[0]))
 	if err != nil {
 		return newUserError("path error:", args[0])
@@ -429,11 +426,7 @@ func (c *importCommand) importFromJekyll(args []string) error {
 	c.r.Println("Importing...")
 
 	fileCount := 0
-	callback := func(path string, fi hugofs.FileMetaInfo, err error) error {
-		if err != nil {
-			return err
-		}
-
+	callback := func(path string, fi hugofs.FileMetaInfo) error {
 		if fi.IsDir() {
 			return nil
 		}
@@ -462,7 +455,7 @@ func (c *importCommand) importFromJekyll(args []string) error {
 
 	for jekyllPostDir, hasAnyPostInDir := range jekyllPostDirs {
 		if hasAnyPostInDir {
-			if err = helpers.SymbolicWalk(hugofs.Os, filepath.Join(jekyllRoot, jekyllPostDir), callback); err != nil {
+			if err = helpers.Walk(hugofs.Os, filepath.Join(jekyllRoot, jekyllPostDir), callback); err != nil {
 				return err
 			}
 		}

commands/list.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -31,7 +31,6 @@ import (
 
 // newListCommand creates a new list command and its subcommands.
 func newListCommand() *listCommand {
-
 	createRecord := func(workingDir string, p page.Page) []string {
 		return []string{
 			filepath.ToSlash(strings.TrimPrefix(p.File().Filename(), workingDir+string(os.PathSeparator))),
@@ -83,7 +82,6 @@ func newListCommand() *listCommand {
 		}
 
 		return nil
-
 	}
 
 	return &listCommand{
@@ -94,11 +92,10 @@ func newListCommand() *listCommand {
 				long:  `List all of the drafts in your content directory.`,
 				run: func(ctx context.Context, cd *simplecobra.Commandeer, r *rootCommand, args []string) error {
 					shouldInclude := func(p page.Page) bool {
-						if !p.Draft() || p.File().IsZero() {
+						if !p.Draft() || p.File() == nil {
 							return false
 						}
 						return true
-
 					}
 					return list(cd, r, shouldInclude,
 						"buildDrafts", true,
@@ -113,11 +110,10 @@ func newListCommand() *listCommand {
 				long:  `List all of the posts in your content directory which will be posted in the future.`,
 				run: func(ctx context.Context, cd *simplecobra.Commandeer, r *rootCommand, args []string) error {
 					shouldInclude := func(p page.Page) bool {
-						if !resource.IsFuture(p) || p.File().IsZero() {
+						if !resource.IsFuture(p) || p.File() == nil {
 							return false
 						}
 						return true
-
 					}
 					return list(cd, r, shouldInclude,
 						"buildFuture", true,
@@ -131,7 +127,7 @@ func newListCommand() *listCommand {
 				long:  `List all of the posts in your content directory which has already expired.`,
 				run: func(ctx context.Context, cd *simplecobra.Commandeer, r *rootCommand, args []string) error {
 					shouldInclude := func(p page.Page) bool {
-						if !resource.IsExpired(p) || p.File().IsZero() {
+						if !resource.IsExpired(p) || p.File() == nil {
 							return false
 						}
 						return true
@@ -148,14 +144,13 @@ func newListCommand() *listCommand {
 				long:  `List all of the posts in your content directory, include drafts, future and expired pages.`,
 				run: func(ctx context.Context, cd *simplecobra.Commandeer, r *rootCommand, args []string) error {
 					shouldInclude := func(p page.Page) bool {
-						return !p.File().IsZero()
+						return p.File() != nil
 					}
 					return list(cd, r, shouldInclude, "buildDrafts", true, "buildFuture", true, "buildExpired", true)
 				},
 			},
 		},
 	}
-
 }
 
 type listCommand struct {

commands/mod.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -69,7 +69,7 @@ so this may/will change in future versions of Hugo.
 					if err != nil {
 						return err
 					}
-					return npm.Pack(h.BaseFs.SourceFs, h.BaseFs.Assets.Dirs)
+					return npm.Pack(h.BaseFs.ProjectSourceFs, h.BaseFs.AssetsWithDuplicatesPreserved.Fs)
 				},
 			},
 		},
@@ -211,7 +211,12 @@ Install a specific version:
 
     hugo mod get github.com/gohugoio/testshortcodes@v0.3.0
 
-Install the latest versions of all module dependencies:
+Install the latest versions of all direct module dependencies:
+
+    hugo mod get
+    hugo mod get ./... (recursive)
+
+Install the latest versions of all module dependencies (direct and indirect):
 
     hugo mod get -u
     hugo mod get -u ./... (recursive)
@@ -281,7 +286,6 @@ Run "go help get" for more information. All flags available for "go get" is also
 			npmCommand,
 		},
 	}
-
 }
 
 type modCommands struct {
@@ -303,7 +307,7 @@ func (c *modCommands) Run(ctx context.Context, cd *simplecobra.Commandeer, args
 	if err != nil {
 		return err
 	}
-	//config := conf.configs.Base
+	// config := conf.configs.Base
 
 	return nil
 }

commands/new.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -63,9 +63,7 @@ Ensure you run this within the root directory of your site.`,
 					cmd.Flags().StringVarP(&contentType, "kind", "k", "", "content type to create")
 					cmd.Flags().String("editor", "", "edit new content with this editor, if provided")
 					cmd.Flags().BoolVarP(&force, "force", "f", false, "overwrite file if it already exists")
-					cmd.Flags().StringVar(&format, "format", "toml", "preferred file format (toml, yaml or json)")
 					applyLocalFlagsBuildConfig(cmd, r)
-
 				},
 			},
 			&simpleCommand{
@@ -144,7 +142,6 @@ according to your needs.`,
 	}
 
 	return c
-
 }
 
 type newCommand struct {

commands/release.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -24,7 +24,6 @@ import (
 // Note: This is a command only meant for internal use and must be run
 // via "go run -tags release main.go release" on the actual code base that is in the release.
 func newReleaseCommand() simplecobra.Commander {
-
 	var (
 		step     int
 		skipPush bool

commands/server.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -25,22 +25,22 @@ import (
 	"io"
 	"net"
 	"net/http"
+	_ "net/http/pprof"
 	"net/url"
 	"os"
-	"sync"
-	"sync/atomic"
-
-	"github.com/bep/mclib"
-
 	"os/signal"
 	"path"
 	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
+	"sync"
+	"sync/atomic"
 	"syscall"
 	"time"
 
+	"github.com/bep/mclib"
+
 	"github.com/bep/debounce"
 	"github.com/bep/simplecobra"
 	"github.com/fsnotify/fsnotify"
@@ -83,10 +83,14 @@ const (
 )
 
 func newHugoBuilder(r *rootCommand, s *serverCommand, onConfigLoaded ...func(reloaded bool) error) *hugoBuilder {
+	var visitedURLs *types.EvictingStringQueue
+	if s != nil && !s.disableFastRender {
+		visitedURLs = types.NewEvictingStringQueue(20)
+	}
 	return &hugoBuilder{
 		r:              r,
 		s:              s,
-		visitedURLs:    types.NewEvictingStringQueue(100),
+		visitedURLs:    visitedURLs,
 		fullRebuildSem: semaphore.NewWeighted(1),
 		debounce:       debounce.New(4 * time.Second),
 		onConfigLoaded: func(reloaded bool) error {
@@ -120,7 +124,6 @@ func newServerCommand() *serverCommand {
 				},
 				withc: func(cmd *cobra.Command, r *rootCommand) {
 					cmd.Flags().BoolVar(&uninstall, "uninstall", false, "Uninstall the local CA (but do not delete it).")
-
 				},
 			},
 		},
@@ -219,7 +222,7 @@ func (f *fileChangeDetector) filterIrrelevant(in []string) []string {
 }
 
 type fileServer struct {
-	baseURLs      []string
+	baseURLs      []urls.BaseURL
 	roots         []string
 	errorTemplate func(err any) (io.Reader, error)
 	c             *serverCommand
@@ -236,12 +239,14 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 	r.Printf("Environment: %q\n", f.c.hugoTry().Deps.Site.Hugo().Environment)
 
 	if i == 0 {
-		if f.c.renderToDisk {
-			r.Println("Serving pages from disk")
-		} else if f.c.renderStaticToDisk {
-			r.Println("Serving pages from memory and static files from disk")
+		mainTarget := "disk"
+		if f.c.r.renderToMemory {
+			mainTarget = "memory"
+		}
+		if f.c.renderStaticToDisk {
+			r.Printf("Serving pages from %s and static files from disk\n", mainTarget)
 		} else {
-			r.Println("Serving pages from memory")
+			r.Printf("Serving pages from %s\n", mainTarget)
 		}
 	}
 
@@ -255,12 +260,6 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 		r.Println("Running in Fast Render Mode. For full rebuilds on change: hugo server --disableFastRender")
 	}
 
-	// We're only interested in the path
-	u, err := url.Parse(baseURL)
-	if err != nil {
-		return nil, nil, "", "", fmt.Errorf("invalid baseURL: %w", err)
-	}
-
 	decorate := func(h http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			if f.c.showErrorInBrowser {
@@ -280,7 +279,7 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 							port = lrport
 						}
 					})
-					lr := *u
+					lr := baseURL.URL()
 					lr.Host = fmt.Sprintf("%s:%d", lr.Hostname(), port)
 					fmt.Fprint(w, injectLiveReloadScript(r, lr))
 
@@ -311,7 +310,7 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 				// This matches Netlify's behaviour and is needed for SPA behaviour.
 				// See https://docs.netlify.com/routing/redirects/rewrites-proxies/
 				if !redirect.Force {
-					path := filepath.Clean(strings.TrimPrefix(requestURI, u.Path))
+					path := filepath.Clean(strings.TrimPrefix(requestURI, baseURL.Path()))
 					if root != "" {
 						path = filepath.Join(root, path)
 					}
@@ -338,7 +337,7 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 					switch redirect.Status {
 					case 404:
 						w.WriteHeader(404)
-						file, err := fs.Open(strings.TrimPrefix(redirect.To, u.Path))
+						file, err := fs.Open(strings.TrimPrefix(redirect.To, baseURL.Path()))
 						if err == nil {
 							defer file.Close()
 							io.Copy(w, file)
@@ -347,7 +346,7 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 						}
 						return
 					case 200:
-						if r2 := f.rewriteRequest(r, strings.TrimPrefix(redirect.To, u.Path)); r2 != nil {
+						if r2 := f.rewriteRequest(r, strings.TrimPrefix(redirect.To, baseURL.Path())); r2 != nil {
 							requestURI = redirect.To
 							r = r2
 						}
@@ -385,10 +384,10 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 
 	fileserver := decorate(http.FileServer(fs))
 	mu := http.NewServeMux()
-	if u.Path == "" || u.Path == "/" {
+	if baseURL.Path() == "" || baseURL.Path() == "/" {
 		mu.Handle("/", fileserver)
 	} else {
-		mu.Handle(u.Path, http.StripPrefix(u.Path, fileserver))
+		mu.Handle(baseURL.Path(), http.StripPrefix(baseURL.Path(), fileserver))
 	}
 	if r.IsTestRun() {
 		var shutDownOnce sync.Once
@@ -401,7 +400,7 @@ func (f *fileServer) createEndpoint(i int) (*http.ServeMux, net.Listener, string
 
 	endpoint := net.JoinHostPort(f.c.serverInterface, strconv.Itoa(port))
 
-	return mu, listener, u.String(), endpoint, nil
+	return mu, listener, baseURL.String(), endpoint, nil
 }
 
 func (f *fileServer) rewriteRequest(r *http.Request, toPath string) *http.Request {
@@ -447,7 +446,6 @@ type serverCommand struct {
 	doLiveReload bool
 
 	// Flags.
-	renderToDisk        bool
 	renderStaticToDisk  bool
 	navigateToChanged   bool
 	serverAppend        bool
@@ -455,6 +453,7 @@ type serverCommand struct {
 	tlsCertFile         string
 	tlsKeyFile          string
 	tlsAuto             bool
+	pprof               bool
 	serverPort          int
 	liveReloadPort      int
 	serverWatch         bool
@@ -469,7 +468,11 @@ func (c *serverCommand) Name() string {
 }
 
 func (c *serverCommand) Run(ctx context.Context, cd *simplecobra.Commandeer, args []string) error {
-
+	if c.pprof {
+		go func() {
+			http.ListenAndServe("localhost:8080", nil)
+		}()
+	}
 	// Watch runs its own server as part of the routine
 	if c.serverWatch {
 
@@ -494,8 +497,7 @@ func (c *serverCommand) Run(ctx context.Context, cd *simplecobra.Commandeer, arg
 
 	err := func() error {
 		defer c.r.timeTrack(time.Now(), "Built")
-		err := c.build()
-		return err
+		return c.build()
 	}()
 	if err != nil {
 		return err
@@ -510,8 +512,9 @@ func (c *serverCommand) Init(cd *simplecobra.Commandeer) error {
 	cmd.Long = `Hugo provides its own webserver which builds and serves the site.
 While hugo server is high performance, it is a webserver with limited options.
 
-'hugo server' will avoid writing the rendered and served content to disk,
-preferring to store it in memory.
+'hugo server' will by default write and server files from disk, but you can
+render to memory by using the '--renderToMemory' flag. This can be faster
+in some cases, but it will consume more memory.
 
 By default hugo will also watch your files for any changes you make and
 automatically rebuild the site. It will then live reload any open browser pages
@@ -525,19 +528,16 @@ of a second, you will be able to save and see your changes nearly instantly.`
 	cmd.Flags().StringVarP(&c.tlsCertFile, "tlsCertFile", "", "", "path to TLS certificate file")
 	cmd.Flags().StringVarP(&c.tlsKeyFile, "tlsKeyFile", "", "", "path to TLS key file")
 	cmd.Flags().BoolVar(&c.tlsAuto, "tlsAuto", false, "generate and use locally-trusted certificates.")
+	cmd.Flags().BoolVar(&c.pprof, "pprof", false, "enable the pprof server (port 8080)")
 	cmd.Flags().BoolVarP(&c.serverWatch, "watch", "w", true, "watch filesystem for changes and recreate as needed")
 	cmd.Flags().BoolVar(&c.noHTTPCache, "noHTTPCache", false, "prevent HTTP caching")
 	cmd.Flags().BoolVarP(&c.serverAppend, "appendPort", "", true, "append port to baseURL")
 	cmd.Flags().BoolVar(&c.disableLiveReload, "disableLiveReload", false, "watch without enabling live browser reload on rebuild")
 	cmd.Flags().BoolVar(&c.navigateToChanged, "navigateToChanged", false, "navigate to changed content file on live browser reload")
-	cmd.Flags().BoolVar(&c.renderToDisk, "renderToDisk", false, "serve all files from disk (default is from memory)")
 	cmd.Flags().BoolVar(&c.renderStaticToDisk, "renderStaticToDisk", false, "serve static files from disk and dynamic files from memory")
 	cmd.Flags().BoolVar(&c.disableFastRender, "disableFastRender", false, "enables full re-renders on changes")
 	cmd.Flags().BoolVar(&c.disableBrowserError, "disableBrowserError", false, "do not show build errors in the browser")
 
-	cmd.Flags().String("memstats", "", "log memory usage to this file")
-	cmd.Flags().String("meminterval", "100ms", "interval to poll memory usage (requires --memstats), valid time units are \"ns\", \"us\" (or \"µs\"), \"ms\", \"s\", \"m\", \"h\".")
-
 	cmd.Flags().SetAnnotation("tlsCertFile", cobra.BashCompSubdirsInDir, []string{})
 	cmd.Flags().SetAnnotation("tlsKeyFile", cobra.BashCompSubdirsInDir, []string{})
 
@@ -582,7 +582,9 @@ func (c *serverCommand) PreRun(cd, runner *simplecobra.Commandeer) error {
 	)
 
 	destinationFlag := cd.CobraCommand.Flags().Lookup("destination")
-	c.renderToDisk = c.renderToDisk || (destinationFlag != nil && destinationFlag.Changed)
+	if c.r.renderToMemory && (destinationFlag != nil && destinationFlag.Changed) {
+		return fmt.Errorf("cannot use --renderToMemory with --destination")
+	}
 	c.doLiveReload = !c.disableLiveReload
 	c.fastRenderMode = !c.disableFastRender
 	c.showErrorInBrowser = c.doLiveReload && !c.disableBrowserError
@@ -676,7 +678,7 @@ func (c *serverCommand) createCertificates(conf *commonConfig) error {
 
 	// Create the directory if it doesn't exist.
 	if _, err := os.Stat(keyDir); os.IsNotExist(err) {
-		if err := os.MkdirAll(keyDir, 0777); err != nil {
+		if err := os.MkdirAll(keyDir, 0o777); err != nil {
 			return err
 		}
 	}
@@ -701,7 +703,6 @@ func (c *serverCommand) createCertificates(conf *commonConfig) error {
 	// Yes, this is unfortunate, but it's currently the only way to use Mkcert as a library.
 	os.Args = []string{"-cert-file", c.tlsCertFile, "-key-file", c.tlsKeyFile, hostname}
 	return mclib.RunMain()
-
 }
 
 func (c *serverCommand) verifyCert(rootPEM, certPEM []byte, name string) error {
@@ -831,9 +832,9 @@ func (c *serverCommand) partialReRender(urls ...string) error {
 		c.errState.setWasErr(false)
 	}()
 	c.errState.setBuildErr(nil)
-	visited := make(map[string]bool)
+	visited := types.NewEvictingStringQueue(len(urls))
 	for _, url := range urls {
-		visited[url] = true
+		visited.Add(url)
 	}
 
 	h, err := c.hugo()
@@ -846,7 +847,7 @@ func (c *serverCommand) partialReRender(urls ...string) error {
 
 func (c *serverCommand) serve() error {
 	var (
-		baseURLs []string
+		baseURLs []urls.BaseURL
 		roots    []string
 		h        *hugolib.HugoSites
 	)
@@ -863,18 +864,17 @@ func (c *serverCommand) serve() error {
 
 		if isMultiHost {
 			for _, l := range conf.configs.ConfigLangs() {
-				baseURLs = append(baseURLs, l.BaseURL().String())
+				baseURLs = append(baseURLs, l.BaseURL())
 				roots = append(roots, l.Language().Lang)
 			}
 		} else {
 			l := conf.configs.GetFirstLanguageConfig()
-			baseURLs = []string{l.BaseURL().String()}
+			baseURLs = []urls.BaseURL{l.BaseURL()}
 			roots = []string{""}
 		}
 
 		return nil
 	})
-
 	if err != nil {
 		return err
 	}
@@ -927,7 +927,7 @@ func (c *serverCommand) serve() error {
 
 	for i := range baseURLs {
 		mu, listener, serverURL, endpoint, err := srv.createEndpoint(i)
-		var srv *http.Server	
+		var srv *http.Server
 		if c.tlsCertFile != "" && c.tlsKeyFile != "" {
 			srv = &http.Server{
 				Addr:    endpoint,
@@ -946,13 +946,9 @@ func (c *serverCommand) serve() error {
 		servers = append(servers, srv)
 
 		if doLiveReload {
-			u, err := url.Parse(helpers.SanitizeURL(baseURLs[i]))
-			if err != nil {
-				return err
-			}
-
-			mu.HandleFunc(u.Path+"/livereload.js", livereload.ServeJS)
-			mu.HandleFunc(u.Path+"/livereload", livereload.Handler)
+			baseURL := baseURLs[i]
+			mu.HandleFunc(baseURL.Path()+"livereload.js", livereload.ServeJS)
+			mu.HandleFunc(baseURL.Path()+"livereload", livereload.Handler)
 		}
 		c.r.Printf("Web Server is available at %s (bind address %s) %s\n", serverURL, c.serverInterface, roots[i])
 		wg1.Go(func() error {
@@ -971,8 +967,12 @@ func (c *serverCommand) serve() error {
 	if c.r.IsTestRun() {
 		// Write a .ready file to disk to signal ready status.
 		// This is where the test is run from.
+		var baseURLs []string
+		for _, baseURL := range srv.baseURLs {
+			baseURLs = append(baseURLs, baseURL.String())
+		}
 		testInfo := map[string]any{
-			"baseURLs": srv.baseURLs,
+			"baseURLs": baseURLs,
 		}
 
 		dir := os.Getenv("WORK")
@@ -983,7 +983,7 @@ func (c *serverCommand) serve() error {
 			if err != nil {
 				return err
 			}
-			err = os.WriteFile(readyFile, b, 0777)
+			err = os.WriteFile(readyFile, b, 0o777)
 			if err != nil {
 				return err
 			}
@@ -1167,7 +1167,7 @@ func cleanErrorLog(content string) string {
 	return strings.Join(keep, ": ")
 }
 
-func injectLiveReloadScript(src io.Reader, baseURL url.URL) string {
+func injectLiveReloadScript(src io.Reader, baseURL *url.URL) string {
 	var b bytes.Buffer
 	chain := transform.Chain{livereloadinject.New(baseURL)}
 	chain.Apply(&b, src)

common/collections/append_test.go

@@ -55,7 +55,7 @@ func TestAppend(t *testing.T) {
 			[]any{&tstSlicerIn1{"c"}},
 			testSlicerInterfaces{&tstSlicerIn1{"a"}, &tstSlicerIn1{"b"}, &tstSlicerIn1{"c"}},
 		},
-		//https://github.com/gohugoio/hugo/issues/5361
+		// https://github.com/gohugoio/hugo/issues/5361
 		{
 			[]string{"a", "b"},
 			[]any{tstSlicers{&tstSlicer{"a"}, &tstSlicer{"b"}}},
@@ -102,14 +102,16 @@ func TestAppendToMultiDimensionalSlice(t *testing.T) {
 		from     []any
 		expected any
 	}{
-		{[][]string{{"a", "b"}},
+		{
+			[][]string{{"a", "b"}},
 			[]any{[]string{"c", "d"}},
 			[][]string{
 				{"a", "b"},
 				{"c", "d"},
 			},
 		},
-		{[][]string{{"a", "b"}},
+		{
+			[][]string{{"a", "b"}},
 			[]any{[]string{"c", "d"}, []string{"e", "f"}},
 			[][]string{
 				{"a", "b"},
@@ -117,7 +119,8 @@ func TestAppendToMultiDimensionalSlice(t *testing.T) {
 				{"e", "f"},
 			},
 		},
-		{[][]string{{"a", "b"}},
+		{
+			[][]string{{"a", "b"}},
 			[]any{[]int{1, 2}},
 			false,
 		},
@@ -130,7 +133,6 @@ func TestAppendToMultiDimensionalSlice(t *testing.T) {
 			c.Assert(result, qt.DeepEquals, test.expected)
 		}
 	}
-
 }
 
 func TestAppendShouldMakeACopyOfTheInputSlice(t *testing.T) {

common/collections/slice.go

@@ -73,7 +73,6 @@ func StringSliceToInterfaceSlice(ss []string) []any {
 		result[i] = s
 	}
 	return result
-
 }
 
 type SortedStringSlice []string

common/collections/slice_test.go

@@ -135,5 +135,4 @@ func TestSortedStringSlice(t *testing.T) {
 	c.Assert(s.Count("b"), qt.Equals, 3)
 	c.Assert(s.Count("z"), qt.Equals, 0)
 	c.Assert(s.Count("a"), qt.Equals, 1)
-
 }

common/collections/stack.go

@@ -0,0 +1,67 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package collections
+
+import "sync"
+
+// Stack is a simple LIFO stack that is safe for concurrent use.
+type Stack[T any] struct {
+	items []T
+	zero  T
+	mu    sync.RWMutex
+}
+
+func NewStack[T any]() *Stack[T] {
+	return &Stack[T]{}
+}
+
+func (s *Stack[T]) Push(item T) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.items = append(s.items, item)
+}
+
+func (s *Stack[T]) Pop() (T, bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if len(s.items) == 0 {
+		return s.zero, false
+	}
+	item := s.items[len(s.items)-1]
+	s.items = s.items[:len(s.items)-1]
+	return item, true
+}
+
+func (s *Stack[T]) Peek() (T, bool) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	if len(s.items) == 0 {
+		return s.zero, false
+	}
+	return s.items[len(s.items)-1], true
+}
+
+func (s *Stack[T]) Len() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.items)
+}
+
+func (s *Stack[T]) Drain() []T {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	items := s.items
+	s.items = nil
+	return items
+}

common/constants/constants.go

@@ -13,13 +13,33 @@
 
 package constants
 
-// Error IDs.
+// Error/Warning IDs.
 // Do not change these values.
 const (
-	ErrIDAmbigousDisableKindTaxonomy = "error-disable-taxonomy"
-	ErrIDAmbigousOutputKindTaxonomy  = "error-output-taxonomy"
-
 	// IDs for remote errors in tpl/data.
 	ErrRemoteGetJSON = "error-remote-getjson"
 	ErrRemoteGetCSV  = "error-remote-getcsv"
+
+	WarnFrontMatterParamsOverrides = "warning-frontmatter-params-overrides"
 )
+
+// Field/method names with special meaning.
+const (
+	FieldRelPermalink = "RelPermalink"
+	FieldPermalink    = "Permalink"
+)
+
+// IsFieldRelOrPermalink returns whether the given name is a RelPermalink or Permalink.
+func IsFieldRelOrPermalink(name string) bool {
+	return name == FieldRelPermalink || name == FieldPermalink
+}
+
+// Resource transformations.
+const (
+	ResourceTransformationFingerprint = "fingerprint"
+)
+
+// IsResourceTransformationLinkChange returns whether the given name is a resource transformation that changes the permalink based on the content.
+func IsResourceTransformationPermalinkHash(name string) bool {
+	return name == ResourceTransformationFingerprint
+}

common/hcontext/context.go

@@ -0,0 +1,46 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package hcontext
+
+import "context"
+
+// ContextDispatcher is a generic interface for setting and getting values from a context.
+type ContextDispatcher[T any] interface {
+	Set(ctx context.Context, value T) context.Context
+	Get(ctx context.Context) T
+}
+
+// NewContextDispatcher creates a new ContextDispatcher with the given key.
+func NewContextDispatcher[T any, R comparable](key R) ContextDispatcher[T] {
+	return keyInContext[T, R]{
+		id: key,
+	}
+}
+
+type keyInContext[T any, R comparable] struct {
+	zero T
+	id   R
+}
+
+func (f keyInContext[T, R]) Get(ctx context.Context) T {
+	v := ctx.Value(f.id)
+	if v == nil {
+		return f.zero
+	}
+	return v.(T)
+}
+
+func (f keyInContext[T, R]) Set(ctx context.Context, value T) context.Context {
+	return context.WithValue(ctx, f.id, value)
+}

common/herrors/error_locator.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -74,7 +74,6 @@ func ContainsMatcher(text string) func(m LineMatcher) int {
 // ErrorContext contains contextual information about an error. This will
 // typically be the lines surrounding some problem in a file.
 type ErrorContext struct {
-
 	// If a match will contain the matched line and up to 2 lines before and after.
 	// Will be empty if no match.
 	Lines []string

common/herrors/error_locator_test.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/herrors/errors.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,14 +15,15 @@
 package herrors
 
 import (
-	"bytes"
 	"errors"
 	"fmt"
 	"io"
 	"os"
+	"regexp"
 	"runtime"
 	"runtime/debug"
-	"strconv"
+	"strings"
+	"time"
 )
 
 // PrintStackTrace prints the current stacktrace to w.
@@ -49,14 +50,22 @@ func Recover(args ...any) {
 	}
 }
 
-// GetGID the current goroutine id. Used only for debugging.
-func GetGID() uint64 {
-	b := make([]byte, 64)
-	b = b[:runtime.Stack(b, false)]
-	b = bytes.TrimPrefix(b, []byte("goroutine "))
-	b = b[:bytes.IndexByte(b, ' ')]
-	n, _ := strconv.ParseUint(string(b), 10, 64)
-	return n
+// IsTimeoutError returns true if the given error is or contains a TimeoutError.
+func IsTimeoutError(err error) bool {
+	return errors.Is(err, &TimeoutError{})
+}
+
+type TimeoutError struct {
+	Duration time.Duration
+}
+
+func (e *TimeoutError) Error() string {
+	return fmt.Sprintf("timeout after %s", e.Duration)
+}
+
+func (e *TimeoutError) Is(target error) bool {
+	_, ok := target.(*TimeoutError)
+	return ok
 }
 
 // IsFeatureNotAvailableError returns true if the given error is or contains a FeatureNotAvailableError.
@@ -109,3 +118,22 @@ func IsNotExist(err error) bool {
 
 	return false
 }
+
+var nilPointerErrRe = regexp.MustCompile(`at <(.*)>: error calling (.*?): runtime error: invalid memory address or nil pointer dereference`)
+
+func ImproveIfNilPointer(inErr error) (outErr error) {
+	outErr = inErr
+
+	m := nilPointerErrRe.FindStringSubmatch(inErr.Error())
+	if len(m) == 0 {
+		return
+	}
+	call := m[1]
+	field := m[2]
+	parts := strings.Split(call, ".")
+	receiverName := parts[len(parts)-2]
+	receiver := strings.Join(parts[:len(parts)-1], ".")
+	s := fmt.Sprintf("– %s is nil; wrap it in if or with: {{ with %s }}{{ .%s }}{{ end }}", receiverName, receiver, field)
+	outErr = errors.New(nilPointerErrRe.ReplaceAllString(inErr.Error(), s))
+	return
+}

common/herrors/errors_test.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -42,5 +42,4 @@ func TestIsFeatureNotAvailableError(t *testing.T) {
 	c.Assert(IsFeatureNotAvailableError(ErrFeatureNotAvailable), qt.Equals, true)
 	c.Assert(IsFeatureNotAvailableError(&FeatureNotAvailableError{}), qt.Equals, true)
 	c.Assert(IsFeatureNotAvailableError(errors.New("asdf")), qt.Equals, false)
-
 }

common/herrors/file_error.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,13 +15,13 @@ package herrors
 
 import (
 	"encoding/json"
-
-	godartsassv1 "github.com/bep/godartsass"
-
+	"errors"
 	"fmt"
 	"io"
 	"path/filepath"
 
+	godartsassv1 "github.com/bep/godartsass"
+
 	"github.com/bep/godartsass/v2"
 	"github.com/bep/golibsass/libsass/libsasserrors"
 	"github.com/gohugoio/hugo/common/paths"
@@ -29,8 +29,6 @@ import (
 	"github.com/pelletier/go-toml/v2"
 	"github.com/spf13/afero"
 	"github.com/tdewolff/parse/v2"
-
-	"errors"
 )
 
 // FileError represents an error when handling a file: Parsing a config file,
@@ -48,6 +46,9 @@ type FileError interface {
 
 	// UpdateContent updates the error with a new ErrorContext from the content of the file.
 	UpdateContent(r io.Reader, linematcher LineMatcherFn) FileError
+
+	// SetFilename sets the filename of the error.
+	SetFilename(filename string) FileError
 }
 
 // Unwrapper can unwrap errors created with fmt.Errorf.
@@ -60,6 +61,11 @@ var (
 	_ Unwrapper = (*fileError)(nil)
 )
 
+func (fe *fileError) SetFilename(filename string) FileError {
+	fe.position.Filename = filename
+	return fe
+}
+
 func (fe *fileError) UpdatePosition(pos text.Position) FileError {
 	oldFilename := fe.Position().Filename
 	if pos.Filename != "" && fe.fileType == "" {
@@ -115,7 +121,6 @@ func (fe *fileError) UpdateContent(r io.Reader, linematcher LineMatcherFn) FileE
 	}
 
 	return fe
-
 }
 
 type fileError struct {
@@ -181,7 +186,6 @@ func NewFileErrorFromName(err error, name string) FileError {
 	}
 
 	return &fileError{cause: err, fileType: fileType, position: pos}
-
 }
 
 // NewFileErrorFromPos will use the filename and line number from pos to create a new FileError, wrapping err.
@@ -192,7 +196,6 @@ func NewFileErrorFromPos(err error, pos text.Position) FileError {
 		_, fileType = paths.FileAndExtNoDelimiter(filepath.Clean(pos.Filename))
 	}
 	return &fileError{cause: err, fileType: fileType, position: pos}
-
 }
 
 func NewFileErrorFromFileInErr(err error, fs afero.Fs, linematcher LineMatcherFn) FileError {
@@ -249,7 +252,6 @@ func openFile(filename string, fs afero.Fs) (afero.File, string, error) {
 		}); ok {
 			realFilename = s.Filename()
 		}
-
 	}
 
 	f, err2 := fs.Open(filename)

common/herrors/file_error_test.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -14,12 +14,11 @@
 package herrors
 
 import (
+	"errors"
 	"fmt"
 	"strings"
 	"testing"
 
-	"errors"
-
 	"github.com/gohugoio/hugo/common/text"
 
 	qt "github.com/frankban/quicktest"
@@ -48,7 +47,6 @@ func TestNewFileError(t *testing.T) {
 	c.Assert(errorContext.Lines, qt.DeepEquals, []string{"line 30", "line 31", "line 32", "line 33", "line 34"})
 	c.Assert(errorContext.LinesPos, qt.Equals, 2)
 	c.Assert(errorContext.ChromaLexer, qt.Equals, "go-html-template")
-
 }
 
 func TestNewFileErrorExtractFromMessage(t *testing.T) {

common/hexec/exec.go

@@ -19,11 +19,10 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"regexp"
-	"strings"
-
 	"os"
 	"os/exec"
+	"regexp"
+	"strings"
 
 	"github.com/cli/safeexec"
 	"github.com/gohugoio/hugo/config"
@@ -142,7 +141,6 @@ func (e *Exec) New(name string, arg ...any) (Runner, error) {
 	}
 
 	return cm.command(arg...)
-
 }
 
 // Npx is a convenience method to create a Runner running npx --no-install <name> <args.

common/hreflect/helpers.go

@@ -1,4 +1,4 @@
-// Copyright 2019 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -23,6 +23,7 @@ import (
 	"time"
 
 	"github.com/gohugoio/hugo/common/htime"
+	"github.com/gohugoio/hugo/common/maps"
 	"github.com/gohugoio/hugo/common/types"
 )
 
@@ -188,6 +189,20 @@ func IsTime(tp reflect.Type) bool {
 	return false
 }
 
+// IsValid returns whether v is not nil and a valid value.
+func IsValid(v reflect.Value) bool {
+	if !v.IsValid() {
+		return false
+	}
+
+	switch v.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return !v.IsNil()
+	}
+
+	return true
+}
+
 // AsTime returns v as a time.Time if possible.
 // The given location is only used if the value implements AsTimeProvider (e.g. go-toml local).
 // A zero Time and false is returned if this isn't possible.
@@ -217,7 +232,7 @@ func CallMethodByName(cxt context.Context, name string, v reflect.Value) []refle
 			panic("not supported")
 		}
 		first := tp.In(0)
-		if first.Implements(ContextInterface) {
+		if IsContextType(first) {
 			args = append(args, reflect.ValueOf(cxt))
 		}
 	}
@@ -236,4 +251,24 @@ func indirectInterface(v reflect.Value) reflect.Value {
 	return v.Elem()
 }
 
-var ContextInterface = reflect.TypeOf((*context.Context)(nil)).Elem()
+var contextInterface = reflect.TypeOf((*context.Context)(nil)).Elem()
+
+var isContextCache = maps.NewCache[reflect.Type, bool]()
+
+type k string
+
+var contextTypeValue = reflect.TypeOf(context.WithValue(context.Background(), k("key"), 32))
+
+// IsContextType returns whether tp is a context.Context type.
+func IsContextType(tp reflect.Type) bool {
+	if tp == contextTypeValue {
+		return true
+	}
+	if tp == contextInterface {
+		return true
+	}
+
+	return isContextCache.GetOrCreate(tp, func() bool {
+		return tp.Implements(contextInterface)
+	})
+}

common/hreflect/helpers_test.go

@@ -14,6 +14,7 @@
 package hreflect
 
 import (
+	"context"
 	"reflect"
 	"testing"
 	"time"
@@ -40,6 +41,42 @@ func TestGetMethodByName(t *testing.T) {
 	c.Assert(GetMethodIndexByName(tp, "Foo"), qt.Equals, -1)
 }
 
+func TestIsContextType(t *testing.T) {
+	c := qt.New(t)
+	type k string
+	ctx := context.Background()
+	valueCtx := context.WithValue(ctx, k("key"), 32)
+	c.Assert(IsContextType(reflect.TypeOf(ctx)), qt.IsTrue)
+	c.Assert(IsContextType(reflect.TypeOf(valueCtx)), qt.IsTrue)
+}
+
+func BenchmarkIsContextType(b *testing.B) {
+	type k string
+	b.Run("value", func(b *testing.B) {
+		ctx := context.Background()
+		ctxs := make([]reflect.Type, b.N)
+		for i := 0; i < b.N; i++ {
+			ctxs[i] = reflect.TypeOf(context.WithValue(ctx, k("key"), i))
+		}
+
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			if !IsContextType(ctxs[i]) {
+				b.Fatal("not context")
+			}
+		}
+	})
+
+	b.Run("background", func(b *testing.B) {
+		var ctxt reflect.Type = reflect.TypeOf(context.Background())
+		for i := 0; i < b.N; i++ {
+			if !IsContextType(ctxt) {
+				b.Fatal("not context")
+			}
+		}
+	})
+}
+
 func BenchmarkIsTruthFul(b *testing.B) {
 	v := reflect.ValueOf("Hugo")
 

common/hstrings/strings.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -99,3 +99,31 @@ var reCache = regexpCache{re: make(map[string]*regexp.Regexp)}
 func GetOrCompileRegexp(pattern string) (re *regexp.Regexp, err error) {
 	return reCache.getOrCompileRegexp(pattern)
 }
+
+// InSlice checks if a string is an element of a slice of strings
+// and returns a boolean value.
+func InSlice(arr []string, el string) bool {
+	for _, v := range arr {
+		if v == el {
+			return true
+		}
+	}
+	return false
+}
+
+// InSlicEqualFold checks if a string is an element of a slice of strings
+// and returns a boolean value.
+// It uses strings.EqualFold to compare.
+func InSlicEqualFold(arr []string, el string) bool {
+	for _, v := range arr {
+		if strings.EqualFold(v, el) {
+			return true
+		}
+	}
+	return false
+}
+
+type Tuple struct {
+	First  string
+	Second string
+}

common/hstrings/strings_test.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -33,7 +33,6 @@ func TestStringEqualFold(t *testing.T) {
 	c.Assert(StringEqualFold(s1).EqualFold("b"), qt.Equals, false)
 	c.Assert(StringEqualFold(s1).Eq(s2), qt.Equals, true)
 	c.Assert(StringEqualFold(s1).Eq("b"), qt.Equals, false)
-
 }
 
 func TestGetOrCompileRegexp(t *testing.T) {
@@ -42,7 +41,6 @@ func TestGetOrCompileRegexp(t *testing.T) {
 	re, err := GetOrCompileRegexp(`\d+`)
 	c.Assert(err, qt.IsNil)
 	c.Assert(re.MatchString("123"), qt.Equals, true)
-
 }
 
 func BenchmarkGetOrCompileRegexp(b *testing.B) {

common/htime/htime_integration_test.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -47,12 +47,7 @@ defaultContentLanguage = 'it'
 {{ end }}
   `
 
-	b := hugolib.NewIntegrationTestBuilder(
-		hugolib.IntegrationTestConfig{
-			T:           t,
-			TxtarString: files,
-		},
-	).Build()
+	b := hugolib.Test(t, files)
 
 	b.AssertFileContent("public/index.html", `
 month: _gennaio_ weekday: _lunedì_

common/htime/time_test.go

@@ -53,7 +53,6 @@ func TestTimeFormatter(t *testing.T) {
 		c.Assert(f.Format(june06, ":time_long"), qt.Equals, "02:09:37 UTC")
 		c.Assert(f.Format(june06, ":time_medium"), qt.Equals, "02:09:37")
 		c.Assert(f.Format(june06, ":time_short"), qt.Equals, "02:09")
-
 	})
 
 	c.Run("Custom layouts English", func(c *qt.C) {
@@ -68,7 +67,6 @@ func TestTimeFormatter(t *testing.T) {
 		c.Assert(f.Format(june06, ":time_long"), qt.Equals, "2:09:37 am UTC")
 		c.Assert(f.Format(june06, ":time_medium"), qt.Equals, "2:09:37 am")
 		c.Assert(f.Format(june06, ":time_short"), qt.Equals, "2:09 am")
-
 	})
 
 	c.Run("English", func(c *qt.C) {
@@ -107,9 +105,7 @@ func TestTimeFormatter(t *testing.T) {
 			c.Assert(tr.MonthWide(date.Month()), qt.Equals, monthWideNorway)
 			c.Assert(f.Format(date, "January"), qt.Equals, monthWideNorway)
 		}
-
 	})
-
 }
 
 func BenchmarkTimeFormatter(b *testing.B) {

common/hugio/copy.go

@@ -16,6 +16,7 @@ package hugio
 import (
 	"fmt"
 	"io"
+	iofs "io/fs"
 	"path/filepath"
 
 	"github.com/spf13/afero"
@@ -60,12 +61,16 @@ func CopyDir(fs afero.Fs, from, to string, shouldCopy func(filename string) bool
 		return fmt.Errorf("%q is not a directory", from)
 	}
 
-	err = fs.MkdirAll(to, 0777) // before umask
+	err = fs.MkdirAll(to, 0o777) // before umask
 	if err != nil {
 		return err
 	}
 
-	entries, _ := afero.ReadDir(fs, from)
+	d, err := fs.Open(from)
+	if err != nil {
+		return err
+	}
+	entries, _ := d.(iofs.ReadDirFile).ReadDir(-1)
 	for _, entry := range entries {
 		fromFilename := filepath.Join(from, entry.Name())
 		toFilename := filepath.Join(to, entry.Name())

common/hugio/hasBytesWriter.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/hugio/hasBytesWriter_test.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/hugio/readers.go

@@ -14,6 +14,7 @@
 package hugio
 
 import (
+	"bytes"
 	"io"
 	"strings"
 )
@@ -36,24 +37,70 @@ type ReadSeekCloserProvider interface {
 	ReadSeekCloser() (ReadSeekCloser, error)
 }
 
-// ReadSeekerNoOpCloser implements ReadSeekCloser by doing nothing in Close.
-// TODO(bep) rename this and similar to ReadSeekerNopCloser, naming used in stdlib, which kind of makes sense.
-type ReadSeekerNoOpCloser struct {
+// readSeekerNopCloser implements ReadSeekCloser by doing nothing in Close.
+type readSeekerNopCloser struct {
 	ReadSeeker
 }
 
 // Close does nothing.
-func (r ReadSeekerNoOpCloser) Close() error {
+func (r readSeekerNopCloser) Close() error {
 	return nil
 }
 
 // NewReadSeekerNoOpCloser creates a new ReadSeekerNoOpCloser with the given ReadSeeker.
-func NewReadSeekerNoOpCloser(r ReadSeeker) ReadSeekerNoOpCloser {
-	return ReadSeekerNoOpCloser{r}
+func NewReadSeekerNoOpCloser(r ReadSeeker) ReadSeekCloser {
+	return readSeekerNopCloser{r}
 }
 
 // NewReadSeekerNoOpCloserFromString uses strings.NewReader to create a new ReadSeekerNoOpCloser
 // from the given string.
-func NewReadSeekerNoOpCloserFromString(content string) ReadSeekerNoOpCloser {
-	return ReadSeekerNoOpCloser{strings.NewReader(content)}
+func NewReadSeekerNoOpCloserFromString(content string) ReadSeekCloser {
+	return stringReadSeeker{s: content, readSeekerNopCloser: readSeekerNopCloser{strings.NewReader(content)}}
+}
+
+var _ StringReader = (*stringReadSeeker)(nil)
+
+type stringReadSeeker struct {
+	s string
+	readSeekerNopCloser
+}
+
+func (s *stringReadSeeker) ReadString() string {
+	return s.s
+}
+
+// StringReader provides a way to read a string.
+type StringReader interface {
+	ReadString() string
+}
+
+// NewReadSeekerNoOpCloserFromString uses strings.NewReader to create a new ReadSeekerNoOpCloser
+// from the given bytes slice.
+func NewReadSeekerNoOpCloserFromBytes(content []byte) readSeekerNopCloser {
+	return readSeekerNopCloser{bytes.NewReader(content)}
+}
+
+// NewReadSeekCloser creates a new ReadSeekCloser from the given ReadSeeker.
+// The ReadSeeker will be seeked to the beginning before returned.
+func NewOpenReadSeekCloser(r ReadSeekCloser) OpenReadSeekCloser {
+	return func() (ReadSeekCloser, error) {
+		r.Seek(0, io.SeekStart)
+		return r, nil
+	}
+}
+
+// OpenReadSeekCloser allows setting some other way (than reading from a filesystem)
+// to open or create a ReadSeekCloser.
+type OpenReadSeekCloser func() (ReadSeekCloser, error)
+
+// ReadString reads from the given reader and returns the content as a string.
+func ReadString(r io.Reader) (string, error) {
+	if sr, ok := r.(StringReader); ok {
+		return sr.ReadString(), nil
+	}
+	b, err := io.ReadAll(r)
+	if err != nil {
+		return "", err
+	}
+	return string(b), nil
 }

common/hugo/hugo.go

@@ -22,18 +22,21 @@ import (
 	"sort"
 	"strings"
 	"sync"
+	"time"
 
 	godartsassv1 "github.com/bep/godartsass"
+	"github.com/bep/logg"
 	"github.com/mitchellh/mapstructure"
 
-	"time"
-
 	"github.com/bep/godartsass/v2"
 	"github.com/gohugoio/hugo/common/hexec"
+	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/hugofs/files"
 
 	"github.com/spf13/afero"
 
+	iofs "io/fs"
+
 	"github.com/gohugoio/hugo/config"
 	"github.com/gohugoio/hugo/hugofs"
 )
@@ -78,10 +81,22 @@ func (i HugoInfo) Generator() template.HTML {
 	return template.HTML(fmt.Sprintf(`<meta name="generator" content="Hugo %s">`, CurrentVersion.String()))
 }
 
+// IsDevelopment reports whether the current running environment is "development".
+func (i HugoInfo) IsDevelopment() bool {
+	return i.Environment == EnvironmentDevelopment
+}
+
+// IsProduction reports whether the current running environment is "production".
 func (i HugoInfo) IsProduction() bool {
 	return i.Environment == EnvironmentProduction
 }
 
+// IsServer reports whether the built-in server is running.
+func (i HugoInfo) IsServer() bool {
+	return i.conf.Running()
+}
+
+// IsExtended reports whether the Hugo binary is the extended version.
 func (i HugoInfo) IsExtended() bool {
 	return IsExtended
 }
@@ -99,6 +114,7 @@ func (i HugoInfo) Deps() []*Dependency {
 // ConfigProvider represents the config options that are relevant for HugoInfo.
 type ConfigProvider interface {
 	Environment() string
+	Running() bool
 	WorkingDir() string
 }
 
@@ -145,7 +161,12 @@ func GetExecEnviron(workDir string, cfg config.AllProvider, fs afero.Fs) []strin
 	config.SetEnvVars(&env, "HUGO_PUBLISHDIR", filepath.Join(workDir, cfg.BaseConfig().PublishDir))
 
 	if fs != nil {
-		fis, err := afero.ReadDir(fs, files.FolderJSConfig)
+		var fis []iofs.DirEntry
+		d, err := fs.Open(files.FolderJSConfig)
+		if err == nil {
+			fis, err = d.(iofs.ReadDirFile).ReadDir(-1)
+		}
+
 		if err == nil {
 			for _, fi := range fis {
 				key := fmt.Sprintf("HUGO_FILE_%s", strings.ReplaceAll(strings.ToUpper(fi.Name()), ".", "_"))
@@ -170,8 +191,10 @@ type buildInfo struct {
 	*debug.BuildInfo
 }
 
-var bInfo *buildInfo
-var bInfoInit sync.Once
+var (
+	bInfo     *buildInfo
+	bInfoInit sync.Once
+)
 
 func getBuildInfo() *buildInfo {
 	bInfoInit.Do(func() {
@@ -198,7 +221,6 @@ func getBuildInfo() *buildInfo {
 				bInfo.GoArch = s.Value
 			}
 		}
-
 	})
 
 	return bInfo
@@ -237,12 +259,12 @@ func GetDependencyListNonGo() []string {
 		deps = append(
 			deps,
 			formatDep("github.com/sass/libsass", "3.6.5"),
-			formatDep("github.com/webmproject/libwebp", "v1.2.4"),
+			formatDep("github.com/webmproject/libwebp", "v1.3.2"),
 		)
 	}
 
 	if dartSass := dartSassVersion(); dartSass.ProtocolVersion != "" {
-		var dartSassPath = "github.com/sass/dart-sass-embedded"
+		dartSassPath := "github.com/sass/dart-sass-embedded"
 		if IsDartSassV2() {
 			dartSassPath = "github.com/sass/dart-sass"
 		}
@@ -333,3 +355,45 @@ var (
 func IsDartSassV2() bool {
 	return !strings.Contains(DartSassBinaryName, "embedded")
 }
+
+// Deprecate informs about a deprecation starting at the given version.
+//
+// A deprecation typically needs a simple change in the template, but doing so will make the template incompatible with older versions.
+// Theme maintainers generally want
+// 1. No warnings or errors in the console when building a Hugo site.
+// 2. Their theme to work for at least the last few Hugo versions.
+func Deprecate(item, alternative string, version string) {
+	level := deprecationLogLevelFromVersion(version)
+	DeprecateLevel(item, alternative, version, level)
+}
+
+// DeprecateLevel informs about a deprecation logging at the given level.
+func DeprecateLevel(item, alternative, version string, level logg.Level) {
+	var msg string
+	if level == logg.LevelError {
+		msg = fmt.Sprintf("%s was deprecated in Hugo %s and will be removed in Hugo %s. %s", item, version, CurrentVersion.Next().ReleaseVersion(), alternative)
+	} else {
+		msg = fmt.Sprintf("%s was deprecated in Hugo %s and will be removed in a future release. %s", item, version, alternative)
+	}
+
+	loggers.Log().Logger().WithLevel(level).WithField(loggers.FieldNameCmd, "deprecated").Logf(msg)
+}
+
+// We ususally do about one minor version a month.
+// We want people to run at least the current and previous version without any warnings.
+// We want people who don't update Hugo that often to see the warnings and errors before we remove the feature.
+func deprecationLogLevelFromVersion(ver string) logg.Level {
+	from := MustParseVersion(ver)
+	to := CurrentVersion
+	minorDiff := to.Minor - from.Minor
+	switch {
+	case minorDiff >= 12:
+		// Start failing the build after about a year.
+		return logg.LevelError
+	case minorDiff >= 6:
+		// Start printing warnings after about six months.
+		return logg.LevelWarn
+	default:
+		return logg.LevelInfo
+	}
+}

common/hugo/hugo_test.go

@@ -17,13 +17,14 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/bep/logg"
 	qt "github.com/frankban/quicktest"
 )
 
 func TestHugoInfo(t *testing.T) {
 	c := qt.New(t)
 
-	conf := testConfig{environment: "production", workingDir: "/mywork"}
+	conf := testConfig{environment: "production", workingDir: "/mywork", running: false}
 	hugoInfo := NewInfo(conf, nil)
 
 	c.Assert(hugoInfo.Version(), qt.Equals, CurrentVersion.Version())
@@ -38,15 +39,34 @@ func TestHugoInfo(t *testing.T) {
 	}
 	c.Assert(hugoInfo.Environment, qt.Equals, "production")
 	c.Assert(string(hugoInfo.Generator()), qt.Contains, fmt.Sprintf("Hugo %s", hugoInfo.Version()))
+	c.Assert(hugoInfo.IsDevelopment(), qt.Equals, false)
 	c.Assert(hugoInfo.IsProduction(), qt.Equals, true)
 	c.Assert(hugoInfo.IsExtended(), qt.Equals, IsExtended)
+	c.Assert(hugoInfo.IsServer(), qt.Equals, false)
 
-	devHugoInfo := NewInfo(testConfig{environment: "development"}, nil)
+	devHugoInfo := NewInfo(testConfig{environment: "development", running: true}, nil)
+	c.Assert(devHugoInfo.IsDevelopment(), qt.Equals, true)
 	c.Assert(devHugoInfo.IsProduction(), qt.Equals, false)
+	c.Assert(devHugoInfo.IsServer(), qt.Equals, true)
+}
+
+func TestDeprecationLogLevelFromVersion(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(deprecationLogLevelFromVersion("0.55.0"), qt.Equals, logg.LevelError)
+	ver := CurrentVersion
+	c.Assert(deprecationLogLevelFromVersion(ver.String()), qt.Equals, logg.LevelInfo)
+	ver.Minor -= 1
+	c.Assert(deprecationLogLevelFromVersion(ver.String()), qt.Equals, logg.LevelInfo)
+	ver.Minor -= 6
+	c.Assert(deprecationLogLevelFromVersion(ver.String()), qt.Equals, logg.LevelWarn)
+	ver.Minor -= 6
+	c.Assert(deprecationLogLevelFromVersion(ver.String()), qt.Equals, logg.LevelError)
 }
 
 type testConfig struct {
 	environment string
+	running     bool
 	workingDir  string
 }
 
@@ -54,6 +74,10 @@ func (c testConfig) Environment() string {
 	return c.environment
 }
 
+func (c testConfig) Running() bool {
+	return c.running
+}
+
 func (c testConfig) WorkingDir() string {
 	return c.workingDir
 }

common/hugo/version.go

@@ -67,8 +67,11 @@ func (h VersionString) String() string {
 
 // Compare implements the compare.Comparer interface.
 func (h VersionString) Compare(other any) int {
-	v := MustParseVersion(h.String())
-	return compareVersions(v, other)
+	return compareVersions(h.Version(), other)
+}
+
+func (h VersionString) Version() Version {
+	return MustParseVersion(h.String())
 }
 
 // Eq implements the compare.Eqer interface.
@@ -264,7 +267,6 @@ func compareFloatWithVersion(v1 float64, v2 Version) int {
 
 	if v1maj > v2.Major {
 		return 1
-
 	}
 
 	if v1maj < v2.Major {
@@ -276,7 +278,6 @@ func compareFloatWithVersion(v1 float64, v2 Version) int {
 	}
 
 	return -1
-
 }
 
 func GoMinorVersion() int {

common/hugo/version_current.go

@@ -17,7 +17,7 @@ package hugo
 // This should be the only one.
 var CurrentVersion = Version{
 	Major:      0,
-	Minor:      119,
+	Minor:      123,
 	PatchLevel: 0,
 	Suffix:     "-DEV",
 }

common/loggers/handlerdefault.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -27,10 +27,9 @@ import (
 	"github.com/fatih/color"
 )
 
-var bold = color.New(color.Bold)
-
 // levelColor mapping.
 var levelColor = [...]*color.Color{
+	logg.LevelTrace: color.New(color.FgWhite),
 	logg.LevelDebug: color.New(color.FgWhite),
 	logg.LevelInfo:  color.New(color.FgBlue),
 	logg.LevelWarn:  color.New(color.FgYellow),
@@ -39,6 +38,7 @@ var levelColor = [...]*color.Color{
 
 // levelString mapping.
 var levelString = [...]string{
+	logg.LevelTrace: "TRACE",
 	logg.LevelDebug: "DEBUG",
 	logg.LevelInfo:  "INFO ",
 	logg.LevelWarn:  "WARN ",

common/loggers/handlersmisc.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -69,7 +69,7 @@ func (h *logLevelCounter) HandleLog(e *logg.Entry) error {
 	return nil
 }
 
-var stopError = fmt.Errorf("stop")
+var errStop = fmt.Errorf("stop")
 
 type logOnceHandler struct {
 	threshold logg.Level
@@ -87,7 +87,7 @@ func (h *logOnceHandler) HandleLog(e *logg.Entry) error {
 	defer h.mu.Unlock()
 	hash := identity.HashUint64(e.Level, e.Message, e.Fields)
 	if h.seen[hash] {
-		return stopError
+		return errStop
 	}
 	h.seen[hash] = true
 	return nil
@@ -107,7 +107,7 @@ type stopHandler struct {
 func (h *stopHandler) HandleLog(e *logg.Entry) error {
 	for _, handler := range h.handlers {
 		if err := handler.HandleLog(e); err != nil {
-			if err == stopError {
+			if err == errStop {
 				return nil
 			}
 			return err
@@ -124,26 +124,13 @@ func (h *suppressStatementsHandler) HandleLog(e *logg.Entry) error {
 	for _, field := range e.Fields {
 		if field.Name == FieldNameStatementID {
 			if h.statements[field.Value.(string)] {
-				return stopError
+				return errStop
 			}
 		}
 	}
 	return nil
 }
 
-// replacer creates a new log handler that does string replacement in log messages.
-func replacer(repl *strings.Replacer) logg.Handler {
-	return logg.HandlerFunc(func(e *logg.Entry) error {
-		e.Message = repl.Replace(e.Message)
-		for i, field := range e.Fields {
-			if s, ok := field.Value.(string); ok {
-				e.Fields[i].Value = repl.Replace(s)
-			}
-		}
-		return nil
-	})
-}
-
 // whiteSpaceTrimmer creates a new log handler that trims whitespace from log messages and string fields.
 func whiteSpaceTrimmer() logg.Handler {
 	return logg.HandlerFunc(func(e *logg.Entry) error {

common/loggers/handlerterminal.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -81,7 +81,7 @@ func (h *noColoursHandler) HandleLog(e *logg.Entry) error {
 		if strings.HasPrefix(field.Name, reservedFieldNamePrefix) {
 			continue
 		}
-		fmt.Fprintf(w, " %s %q", field.Name, field.Value)
+		fmt.Fprintf(w, " %s %v", field.Name, field.Value)
 
 	}
 	fmt.Fprintln(w)

common/loggers/logger.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -40,7 +40,7 @@ type Options struct {
 	Level              logg.Level
 	Stdout             io.Writer
 	Stderr             io.Writer
-	Distinct           bool
+	DistinctLevel      logg.Level
 	StoreErrors        bool
 	HandlerPost        func(e *logg.Entry) error
 	SuppressStatements map[string]bool
@@ -68,11 +68,24 @@ func New(opts Options) Logger {
 	errorsw := &strings.Builder{}
 	logCounters := newLogLevelCounter()
 	handlers := []logg.Handler{
-		whiteSpaceTrimmer(),
-		logHandler,
 		logCounters,
 	}
 
+	if opts.Level == logg.LevelTrace {
+		// Trace is used during development only, and it's useful to
+		// only see the trace messages.
+		handlers = append(handlers,
+			logg.HandlerFunc(func(e *logg.Entry) error {
+				if e.Level != logg.LevelTrace {
+					return logg.ErrStopLogEntry
+				}
+				return nil
+			}),
+		)
+	}
+
+	handlers = append(handlers, whiteSpaceTrimmer(), logHandler)
+
 	if opts.HandlerPost != nil {
 		var hookHandler logg.HandlerFunc = func(e *logg.Entry) error {
 			opts.HandlerPost(e)
@@ -92,8 +105,8 @@ func New(opts Options) Logger {
 	logHandler = multi.New(handlers...)
 
 	var logOnce *logOnceHandler
-	if opts.Distinct {
-		logOnce = newLogOnceHandler(logg.LevelWarn)
+	if opts.DistinctLevel != 0 {
+		logOnce = newLogOnceHandler(opts.DistinctLevel)
 		logHandler = newStopHandler(logOnce, logHandler)
 	}
 
@@ -127,6 +140,7 @@ func New(opts Options) Logger {
 		out:         opts.Stdout,
 		level:       opts.Level,
 		logger:      logger,
+		tracel:      l.WithLevel(logg.LevelTrace),
 		debugl:      l.WithLevel(logg.LevelDebug),
 		infol:       l.WithLevel(logg.LevelInfo),
 		warnl:       l.WithLevel(logg.LevelWarn),
@@ -137,10 +151,20 @@ func New(opts Options) Logger {
 // NewDefault creates a new logger with the default options.
 func NewDefault() Logger {
 	opts := Options{
-		Distinct: true,
-		Level:    logg.LevelWarn,
-		Stdout:   os.Stdout,
-		Stderr:   os.Stdout,
+		DistinctLevel: logg.LevelWarn,
+		Level:         logg.LevelWarn,
+		Stdout:        os.Stdout,
+		Stderr:        os.Stdout,
+	}
+	return New(opts)
+}
+
+func NewTrace() Logger {
+	opts := Options{
+		DistinctLevel: logg.LevelWarn,
+		Level:         logg.LevelTrace,
+		Stdout:        os.Stdout,
+		Stderr:        os.Stdout,
 	}
 	return New(opts)
 }
@@ -150,13 +174,14 @@ func LevelLoggerToWriter(l logg.LevelLogger) io.Writer {
 }
 
 type Logger interface {
+	Debug() logg.LevelLogger
 	Debugf(format string, v ...any)
 	Debugln(v ...any)
 	Error() logg.LevelLogger
 	Errorf(format string, v ...any)
+	Erroridf(id, format string, v ...any)
 	Errorln(v ...any)
 	Errors() string
-	Errorsf(id, format string, v ...any)
 	Info() logg.LevelLogger
 	InfoCommand(command string) logg.LevelLogger
 	Infof(format string, v ...any)
@@ -172,8 +197,10 @@ type Logger interface {
 	Warn() logg.LevelLogger
 	WarnCommand(command string) logg.LevelLogger
 	Warnf(format string, v ...any)
+	Warnidf(id, format string, v ...any)
 	Warnln(v ...any)
 	Deprecatef(fail bool, format string, v ...any)
+	Trace(s logg.StringFunc)
 }
 
 type logAdapter struct {
@@ -183,12 +210,17 @@ type logAdapter struct {
 	out         io.Writer
 	level       logg.Level
 	logger      logg.Logger
+	tracel      logg.LevelLogger
 	debugl      logg.LevelLogger
 	infol       logg.LevelLogger
 	warnl       logg.LevelLogger
 	errorl      logg.LevelLogger
 }
 
+func (l *logAdapter) Debug() logg.LevelLogger {
+	return l.debugl
+}
+
 func (l *logAdapter) Debugf(format string, v ...any) {
 	l.debugl.Logf(format, v...)
 }
@@ -290,10 +322,24 @@ func (l *logAdapter) Errors() string {
 	return l.errors.String()
 }
 
-func (l *logAdapter) Errorsf(id, format string, v ...any) {
+func (l *logAdapter) Erroridf(id, format string, v ...any) {
+	format += l.idfInfoStatement("error", id, format)
 	l.errorl.WithField(FieldNameStatementID, id).Logf(format, v...)
 }
 
+func (l *logAdapter) Warnidf(id, format string, v ...any) {
+	format += l.idfInfoStatement("warning", id, format)
+	l.warnl.WithField(FieldNameStatementID, id).Logf(format, v...)
+}
+
+func (l *logAdapter) idfInfoStatement(what, id, format string) string {
+	return fmt.Sprintf("\nYou can suppress this %s by adding the following to your site configuration:\nignoreLogs = ['%s']", what, id)
+}
+
+func (l *logAdapter) Trace(s logg.StringFunc) {
+	l.tracel.Log(s)
+}
+
 func (l *logAdapter) sprint(v ...any) string {
 	return strings.TrimRight(fmt.Sprintln(v...), "\n")
 }
@@ -315,3 +361,19 @@ func (w logWriter) Write(p []byte) (n int, err error) {
 	w.l.Log(logg.String(string(p)))
 	return len(p), nil
 }
+
+func TimeTrackf(l logg.LevelLogger, start time.Time, fields logg.Fields, format string, a ...any) {
+	elapsed := time.Since(start)
+	if fields != nil {
+		l = l.WithFields(fields)
+	}
+	l.WithField("duration", elapsed).Logf(format, a...)
+}
+
+func TimeTrackfn(fn func() (logg.LevelLogger, error)) error {
+	start := time.Now()
+	l, err := fn()
+	elapsed := time.Since(start)
+	l.WithField("duration", elapsed).Logf("")
+	return err
+}

common/loggers/logger_test.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -29,10 +29,10 @@ func TestLogDistinct(t *testing.T) {
 	c := qt.New(t)
 
 	opts := loggers.Options{
-		Distinct:    true,
-		StoreErrors: true,
-		Stdout:      io.Discard,
-		Stderr:      io.Discard,
+		DistinctLevel: logg.LevelWarn,
+		StoreErrors:   true,
+		Stdout:        io.Discard,
+		Stderr:        io.Discard,
 	}
 
 	l := loggers.New(opts)
@@ -85,7 +85,6 @@ func TestOptionStoreErrors(t *testing.T) {
 
 	c.Assert(sb.String(), qt.Contains, "error 1")
 	c.Assert(sb.String(), qt.Contains, "ERROR")
-
 }
 
 func TestLogCount(t *testing.T) {
@@ -124,17 +123,16 @@ func TestSuppressStatements(t *testing.T) {
 	c.Assert(errorsStr, qt.Not(qt.Contains), "error 1")
 	c.Assert(errorsStr, qt.Contains, "error 2")
 	c.Assert(l.LoggCount(logg.LevelError), qt.Equals, 1)
-
 }
 
 func TestReset(t *testing.T) {
 	c := qt.New(t)
 
 	opts := loggers.Options{
-		StoreErrors: true,
-		Distinct:    true,
-		Stdout:      io.Discard,
-		Stderr:      io.Discard,
+		StoreErrors:   true,
+		DistinctLevel: logg.LevelWarn,
+		Stdout:        io.Discard,
+		Stderr:        io.Discard,
 	}
 
 	l := loggers.New(opts)

common/loggers/loggerglobal.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 // Some functions in this file (see comments) is based on the Go source code,
 // copyright The Go Authors and  governed by a BSD-style license.
 //
@@ -21,7 +21,7 @@ import (
 	"github.com/bep/logg"
 )
 
-func InitGlobalLogger(panicOnWarnings bool) {
+func InitGlobalLogger(level logg.Level, panicOnWarnings bool) {
 	logMu.Lock()
 	defer logMu.Unlock()
 	var logHookLast func(e *logg.Entry) error
@@ -31,8 +31,9 @@ func InitGlobalLogger(panicOnWarnings bool) {
 
 	log = New(
 		Options{
-			Distinct:    true,
-			HandlerPost: logHookLast,
+			Level:         level,
+			DistinctLevel: logg.LevelInfo,
+			HandlerPost:   logHookLast,
 		},
 	)
 }
@@ -49,5 +50,5 @@ func Log() Logger {
 var log Logger
 
 func init() {
-	InitGlobalLogger(false)
+	InitGlobalLogger(logg.LevelWarn, false)
 }

common/maps/cache.go

@@ -0,0 +1,90 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package maps
+
+import "sync"
+
+// Cache is a simple thread safe cache backed by a map.
+type Cache[K comparable, T any] struct {
+	m map[K]T
+	sync.RWMutex
+}
+
+// NewCache creates a new Cache.
+func NewCache[K comparable, T any]() *Cache[K, T] {
+	return &Cache[K, T]{m: make(map[K]T)}
+}
+
+// Delete deletes the given key from the cache.
+func (c *Cache[K, T]) Get(key K) (T, bool) {
+	c.RLock()
+	v, found := c.m[key]
+	c.RUnlock()
+	return v, found
+}
+
+// GetOrCreate gets the value for the given key if it exists, or creates it if not.
+func (c *Cache[K, T]) GetOrCreate(key K, create func() T) T {
+	c.RLock()
+	v, found := c.m[key]
+	c.RUnlock()
+	if found {
+		return v
+	}
+	c.Lock()
+	defer c.Unlock()
+	v, found = c.m[key]
+	if found {
+		return v
+	}
+	v = create()
+	c.m[key] = v
+	return v
+}
+
+// Set sets the given key to the given value.
+func (c *Cache[K, T]) Set(key K, value T) {
+	c.Lock()
+	c.m[key] = value
+	c.Unlock()
+}
+
+// SliceCache is a simple thread safe cache backed by a map.
+type SliceCache[T any] struct {
+	m map[string][]T
+	sync.RWMutex
+}
+
+func NewSliceCache[T any]() *SliceCache[T] {
+	return &SliceCache[T]{m: make(map[string][]T)}
+}
+
+func (c *SliceCache[T]) Get(key string) ([]T, bool) {
+	c.RLock()
+	v, found := c.m[key]
+	c.RUnlock()
+	return v, found
+}
+
+func (c *SliceCache[T]) Append(key string, values ...T) {
+	c.Lock()
+	c.m[key] = append(c.m[key], values...)
+	c.Unlock()
+}
+
+func (c *SliceCache[T]) Reset() {
+	c.Lock()
+	c.m = make(map[string][]T)
+	c.Unlock()
+}

common/maps/maps.go

@@ -29,7 +29,7 @@ func ToStringMapE(in any) (map[string]any, error) {
 	case Params:
 		return vv, nil
 	case map[string]string:
-		var m = map[string]any{}
+		m := map[string]any{}
 		for k, v := range vv {
 			m[k] = v
 		}
@@ -192,21 +192,20 @@ func (KeyRenamer) keyPath(k1, k2 string) string {
 }
 
 func (r KeyRenamer) renamePath(parentKeyPath string, m map[string]any) {
-	for key, val := range m {
-		keyPath := r.keyPath(parentKeyPath, key)
-		switch val.(type) {
+	for k, v := range m {
+		keyPath := r.keyPath(parentKeyPath, k)
+		switch vv := v.(type) {
 		case map[any]any:
-			val = cast.ToStringMap(val)
-			r.renamePath(keyPath, val.(map[string]any))
+			r.renamePath(keyPath, cast.ToStringMap(vv))
 		case map[string]any:
-			r.renamePath(keyPath, val.(map[string]any))
+			r.renamePath(keyPath, vv)
 		}
 
 		newKey := r.getNewKey(keyPath)
 
 		if newKey != "" {
-			delete(m, key)
-			m[newKey] = val
+			delete(m, k)
+			m[newKey] = v
 		}
 	}
 }

common/maps/maps_test.go

@@ -192,5 +192,4 @@ func TestLookupEqualFold(t *testing.T) {
 	v, found = LookupEqualFold(m2, "b")
 	c.Assert(found, qt.IsTrue)
 	c.Assert(v, qt.Equals, "bv")
-
 }

common/maps/params.go

@@ -61,7 +61,7 @@ func SetParams(dst, src Params) {
 
 // IsZero returns true if p is considered empty.
 func (p Params) IsZero() bool {
-	if p == nil || len(p) == 0 {
+	if len(p) == 0 {
 		return true
 	}
 
@@ -74,7 +74,6 @@ func (p Params) IsZero() bool {
 	}
 
 	return false
-
 }
 
 // MergeParamsWithStrategy transfers values from src to dst for new keys using the merge strategy given.
@@ -93,7 +92,7 @@ func MergeParams(dst, src Params) {
 func (p Params) merge(ps ParamsMergeStrategy, pp Params) {
 	ns, found := p.GetMergeStrategy()
 
-	var ms = ns
+	ms := ns
 	if !found && ps != "" {
 		ms = ps
 	}
@@ -248,7 +247,7 @@ const (
 // CleanConfigStringMapString removes any processing instructions from m,
 // m will never be modified.
 func CleanConfigStringMapString(m map[string]string) map[string]string {
-	if m == nil || len(m) == 0 {
+	if len(m) == 0 {
 		return m
 	}
 	if _, found := m[MergeStrategyKey]; !found {
@@ -267,7 +266,7 @@ func CleanConfigStringMapString(m map[string]string) map[string]string {
 // CleanConfigStringMap is the same as CleanConfigStringMapString but for
 // map[string]any.
 func CleanConfigStringMap(m map[string]any) map[string]any {
-	if m == nil || len(m) == 0 {
+	if len(m) == 0 {
 		return m
 	}
 	if _, found := m[MergeStrategyKey]; !found {
@@ -291,7 +290,6 @@ func CleanConfigStringMap(m map[string]any) map[string]any {
 
 	}
 	return m2
-
 }
 
 func toMergeStrategy(v any) ParamsMergeStrategy {

common/maps/params_test.go

@@ -154,7 +154,6 @@ func TestParamsSetAndMerge(t *testing.T) {
 		"a": "av",
 		"c": "cv",
 	})
-
 }
 
 func TestParamsIsZero(t *testing.T) {

common/para/para_test.go

@@ -32,8 +32,9 @@ func TestPara(t *testing.T) {
 		t.Skipf("skip para test, CPU count is %d", runtime.NumCPU())
 	}
 
-	if !htesting.IsCI() {
-		t.Skip("skip para test when not running on CI")
+	// TODO(bep)
+	if htesting.IsCI() {
+		t.Skip("skip para test when running on CI")
 	}
 
 	c := qt.New(t)

common/paths/path.go

@@ -16,14 +16,18 @@ package paths
 import (
 	"errors"
 	"fmt"
+	"net/url"
 	"path"
 	"path/filepath"
-	"regexp"
 	"strings"
+	"unicode"
 )
 
 // FilePathSeparator as defined by os.Separator.
-const FilePathSeparator = string(filepath.Separator)
+const (
+	FilePathSeparator = string(filepath.Separator)
+	slash             = "/"
+)
 
 // filepathPathBridge is a bridge for common functionality in filepath vs path
 type filepathPathBridge interface {
@@ -72,6 +76,30 @@ func AbsPathify(workingDir, inPath string) string {
 	return filepath.Join(workingDir, inPath)
 }
 
+// AddTrailingSlash adds a trailing Unix styled slash (/) if not already
+// there.
+func AddTrailingSlash(path string) string {
+	if !strings.HasSuffix(path, "/") {
+		path += "/"
+	}
+	return path
+}
+
+// AddLeadingSlash adds a leading Unix styled slash (/) if not already
+// there.
+func AddLeadingSlash(path string) string {
+	if !strings.HasPrefix(path, "/") {
+		path = "/" + path
+	}
+	return path
+}
+
+// AddTrailingAndLeadingSlash adds a leading and trailing Unix styled slash (/) if not already
+// there.
+func AddLeadingAndTrailingSlash(path string) string {
+	return AddTrailingSlash(AddLeadingSlash(path))
+}
+
 // MakeTitle converts the path given to a suitable title, trimming whitespace
 // and replacing hyphens with whitespace.
 func MakeTitle(inpath string) string {
@@ -94,43 +122,6 @@ func makePathRelative(inPath string, possibleDirectories ...string) (string, err
 	return inPath, errors.New("can't extract relative path, unknown prefix")
 }
 
-// Should be good enough for Hugo.
-var isFileRe = regexp.MustCompile(`.*\..{1,6}$`)
-
-// GetDottedRelativePath expects a relative path starting after the content directory.
-// It returns a relative path with dots ("..") navigating up the path structure.
-func GetDottedRelativePath(inPath string) string {
-	inPath = path.Clean(filepath.ToSlash(inPath))
-
-	if inPath == "." {
-		return "./"
-	}
-
-	if !isFileRe.MatchString(inPath) && !strings.HasSuffix(inPath, "/") {
-		inPath += "/"
-	}
-
-	if !strings.HasPrefix(inPath, "/") {
-		inPath = "/" + inPath
-	}
-
-	dir, _ := filepath.Split(inPath)
-
-	sectionCount := strings.Count(dir, "/")
-
-	if sectionCount == 0 || dir == "/" {
-		return "./"
-	}
-
-	var dottedPath string
-
-	for i := 1; i < sectionCount; i++ {
-		dottedPath += "../"
-	}
-
-	return dottedPath
-}
-
 // ExtNoDelimiter takes a path and returns the extension, excluding the delimiter, i.e. "md".
 func ExtNoDelimiter(in string) string {
 	return strings.TrimPrefix(Ext(in), ".")
@@ -167,12 +158,6 @@ func Filename(in string) (name string) {
 	return
 }
 
-// PathNoExt takes a path, strips out the extension,
-// and returns the name of the file.
-func PathNoExt(in string) string {
-	return strings.TrimSuffix(in, path.Ext(in))
-}
-
 // FileAndExt returns the filename and any extension of a file path as
 // two separate strings.
 //
@@ -252,16 +237,125 @@ func prettifyPath(in string, b filepathPathBridge) string {
 	return b.Join(b.Dir(in), name, "index"+ext)
 }
 
-type NamedSlice struct {
-	Name  string
-	Slice []string
+// CommonDir returns the common directory of the given paths.
+func CommonDir(path1, path2 string) string {
+	if path1 == "" || path2 == "" {
+		return ""
+	}
+
+	p1 := strings.Split(path1, "/")
+	p2 := strings.Split(path2, "/")
+
+	var common []string
+
+	for i := 0; i < len(p1) && i < len(p2); i++ {
+		if p1[i] == p2[i] {
+			common = append(common, p1[i])
+		} else {
+			break
+		}
+	}
+
+	return strings.Join(common, "/")
 }
 
-func (n NamedSlice) String() string {
-	if len(n.Slice) == 0 {
-		return n.Name
+// Sanitize sanitizes string to be used in Hugo's file paths and URLs, allowing only
+// a predefined set of special Unicode characters.
+//
+// Spaces will be replaced with a single hyphen.
+//
+// This function is the core function used to normalize paths in Hugo.
+//
+// Note that this is the first common step for URL/path sanitation,
+// the final URL/path may end up looking differently  if the user has stricter rules defined (e.g. removePathAccents=true).
+func Sanitize(s string) string {
+	var willChange bool
+	for i, r := range s {
+		willChange = !isAllowedPathCharacter(s, i, r)
+		if willChange {
+			break
+		}
 	}
-	return fmt.Sprintf("%s%s{%s}", n.Name, FilePathSeparator, strings.Join(n.Slice, ","))
+
+	if !willChange {
+		// Prevent allocation when nothing changes.
+		return s
+	}
+
+	target := make([]rune, 0, len(s))
+	var (
+		prependHyphen bool
+		wasHyphen     bool
+	)
+
+	for i, r := range s {
+		isAllowed := isAllowedPathCharacter(s, i, r)
+
+		if isAllowed {
+			// track explicit hyphen in input; no need to add a new hyphen if
+			// we just saw one.
+			wasHyphen = r == '-'
+
+			if prependHyphen {
+				// if currently have a hyphen, don't prepend an extra one
+				if !wasHyphen {
+					target = append(target, '-')
+				}
+				prependHyphen = false
+			}
+			target = append(target, r)
+		} else if len(target) > 0 && !wasHyphen && unicode.IsSpace(r) {
+			prependHyphen = true
+		}
+	}
+
+	return string(target)
+}
+
+func isAllowedPathCharacter(s string, i int, r rune) bool {
+	if r == ' ' {
+		return false
+	}
+	// Check for the most likely first (faster).
+	isAllowed := unicode.IsLetter(r) || unicode.IsDigit(r)
+	isAllowed = isAllowed || r == '.' || r == '/' || r == '\\' || r == '_' || r == '#' || r == '+' || r == '~' || r == '-' || r == '@'
+	isAllowed = isAllowed || unicode.IsMark(r)
+	isAllowed = isAllowed || (r == '%' && i+2 < len(s) && ishex(s[i+1]) && ishex(s[i+2]))
+	return isAllowed
+}
+
+// From https://golang.org/src/net/url/url.go
+func ishex(c byte) bool {
+	switch {
+	case '0' <= c && c <= '9':
+		return true
+	case 'a' <= c && c <= 'f':
+		return true
+	case 'A' <= c && c <= 'F':
+		return true
+	}
+	return false
+}
+
+var slashFunc = func(r rune) bool {
+	return r == '/'
+}
+
+// Dir behaves like path.Dir without the path.Clean step.
+//
+//	The returned path ends in a slash only if it is the root "/".
+func Dir(s string) string {
+	dir, _ := path.Split(s)
+	if len(dir) > 1 && dir[len(dir)-1] == '/' {
+		return dir[:len(dir)-1]
+	}
+	return dir
+}
+
+// FieldsSlash cuts s into fields separated with '/'.
+func FieldsSlash(s string) []string {
+	f := strings.FieldsFunc(s, slashFunc)
+	return f
 }
 
 // DirFile holds the result from path.Split.
@@ -274,3 +368,32 @@ type DirFile struct {
 func (df DirFile) String() string {
 	return fmt.Sprintf("%s|%s", df.Dir, df.File)
 }
+
+// PathEscape escapes unicode letters in pth.
+// Use URLEscape to escape full URLs including scheme, query etc.
+// This is slightly faster for the common case.
+// Note, there is a url.PathEscape function, but that also
+// escapes /.
+func PathEscape(pth string) string {
+	u, err := url.Parse(pth)
+	if err != nil {
+		panic(err)
+	}
+	return u.EscapedPath()
+}
+
+// ToSlashTrimLeading is just a filepath.ToSlash with an added / prefix trimmer.
+func ToSlashTrimLeading(s string) string {
+	return strings.TrimPrefix(filepath.ToSlash(s), "/")
+}
+
+// ToSlashTrimTrailing is just a filepath.ToSlash with an added / suffix trimmer.
+func ToSlashTrimTrailing(s string) string {
+	return strings.TrimSuffix(filepath.ToSlash(s), "/")
+}
+
+// ToSlashPreserveLeading converts the path given to a forward slash separated path
+// and preserves the leading slash if present trimming any trailing slash.
+func ToSlashPreserveLeading(s string) string {
+	return "/" + strings.Trim(filepath.ToSlash(s), "/")
+}

common/paths/path_test.go

@@ -1,4 +1,4 @@
-// Copyright 2021 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -75,44 +75,6 @@ func TestMakePathRelative(t *testing.T) {
 	}
 }
 
-func TestGetDottedRelativePath(t *testing.T) {
-	// on Windows this will receive both kinds, both country and western ...
-	for _, f := range []func(string) string{filepath.FromSlash, func(s string) string { return s }} {
-		doTestGetDottedRelativePath(f, t)
-	}
-}
-
-func doTestGetDottedRelativePath(urlFixer func(string) string, t *testing.T) {
-	type test struct {
-		input, expected string
-	}
-	data := []test{
-		{"", "./"},
-		{urlFixer("/"), "./"},
-		{urlFixer("post"), "../"},
-		{urlFixer("/post"), "../"},
-		{urlFixer("post/"), "../"},
-		{urlFixer("tags/foo.html"), "../"},
-		{urlFixer("/tags/foo.html"), "../"},
-		{urlFixer("/post/"), "../"},
-		{urlFixer("////post/////"), "../"},
-		{urlFixer("/foo/bar/index.html"), "../../"},
-		{urlFixer("/foo/bar/foo/"), "../../../"},
-		{urlFixer("/foo/bar/foo"), "../../../"},
-		{urlFixer("foo/bar/foo/"), "../../../"},
-		{urlFixer("foo/bar/foo/bar"), "../../../../"},
-		{"404.html", "./"},
-		{"404.xml", "./"},
-		{"/404.html", "./"},
-	}
-	for i, d := range data {
-		output := GetDottedRelativePath(d.input)
-		if d.expected != output {
-			t.Errorf("Test %d failed. Expected %q got %q", i, d.expected, output)
-		}
-	}
-}
-
 func TestMakeTitle(t *testing.T) {
 	type test struct {
 		input, expected string
@@ -226,3 +188,77 @@ func TestFileAndExt(t *testing.T) {
 		}
 	}
 }
+
+func TestSanitize(t *testing.T) {
+	c := qt.New(t)
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"  Foo bar  ", "Foo-bar"},
+		{"Foo.Bar/foo_Bar-Foo", "Foo.Bar/foo_Bar-Foo"},
+		{"fOO,bar:foobAR", "fOObarfoobAR"},
+		{"FOo/BaR.html", "FOo/BaR.html"},
+		{"FOo/Ba---R.html", "FOo/Ba---R.html"}, /// See #10104
+		{"FOo/Ba       R.html", "FOo/Ba-R.html"},
+		{"трям/трям", "трям/трям"},
+		{"은행", "은행"},
+		{"Банковский кассир", "Банковский-кассир"},
+		// Issue #1488
+		{"संस्कृत", "संस्कृत"},
+		{"a%C3%B1ame", "a%C3%B1ame"},         // Issue #1292
+		{"this+is+a+test", "this+is+a+test"}, // Issue #1290
+		{"~foo", "~foo"},                     // Issue #2177
+
+	}
+
+	for _, test := range tests {
+		c.Assert(Sanitize(test.input), qt.Equals, test.expected)
+	}
+}
+
+func BenchmarkSanitize(b *testing.B) {
+	const (
+		allAlowedPath = "foo/bar"
+		spacePath     = "foo bar"
+	)
+
+	// This should not allocate any memory.
+	b.Run("All allowed", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			got := Sanitize(allAlowedPath)
+			if got != allAlowedPath {
+				b.Fatal(got)
+			}
+		}
+	})
+
+	// This will allocate some memory.
+	b.Run("Spaces", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			got := Sanitize(spacePath)
+			if got != "foo-bar" {
+				b.Fatal(got)
+			}
+		}
+	})
+}
+
+func TestDir(t *testing.T) {
+	c := qt.New(t)
+	c.Assert(Dir("/a/b/c/d"), qt.Equals, "/a/b/c")
+	c.Assert(Dir("/a"), qt.Equals, "/")
+	c.Assert(Dir("/"), qt.Equals, "/")
+	c.Assert(Dir(""), qt.Equals, "")
+}
+
+func TestFieldsSlash(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(FieldsSlash("a/b/c"), qt.DeepEquals, []string{"a", "b", "c"})
+	c.Assert(FieldsSlash("/a/b/c"), qt.DeepEquals, []string{"a", "b", "c"})
+	c.Assert(FieldsSlash("/a/b/c/"), qt.DeepEquals, []string{"a", "b", "c"})
+	c.Assert(FieldsSlash("a/b/c/"), qt.DeepEquals, []string{"a", "b", "c"})
+	c.Assert(FieldsSlash("/"), qt.DeepEquals, []string{})
+	c.Assert(FieldsSlash(""), qt.DeepEquals, []string{})
+}

common/paths/pathparser.go

@@ -0,0 +1,511 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package paths
+
+import (
+	"path"
+	"path/filepath"
+	"runtime"
+	"strings"
+
+	"github.com/gohugoio/hugo/common/types"
+	"github.com/gohugoio/hugo/hugofs/files"
+)
+
+var defaultPathParser PathParser
+
+// PathParser parses a path into a Path.
+type PathParser struct {
+	// Maps the language code to its index in the languages/sites slice.
+	LanguageIndex map[string]int
+
+	// Reports whether the given language is disabled.
+	IsLangDisabled func(string) bool
+}
+
+// Parse parses component c with path s into Path using the default path parser.
+func Parse(c, s string) *Path {
+	return defaultPathParser.Parse(c, s)
+}
+
+// NormalizePathString returns a normalized path string using the very basic Hugo rules.
+func NormalizePathStringBasic(s string) string {
+	// All lower case.
+	s = strings.ToLower(s)
+
+	// Replace spaces with hyphens.
+	s = strings.ReplaceAll(s, " ", "-")
+
+	return s
+}
+
+// Parse parses component c with path s into Path using Hugo's content path rules.
+func (parser PathParser) Parse(c, s string) *Path {
+	p, err := parser.parse(c, s)
+	if err != nil {
+		panic(err)
+	}
+	return p
+}
+
+func (pp *PathParser) parse(component, s string) (*Path, error) {
+	ss := NormalizePathStringBasic(s)
+
+	p, err := pp.doParse(component, ss)
+	if err != nil {
+		return nil, err
+	}
+
+	if s != ss {
+		var err error
+		// Preserve the original case for titles etc.
+		p.unnormalized, err = pp.doParse(component, s)
+
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		p.unnormalized = p
+	}
+
+	return p, nil
+}
+
+func (pp *PathParser) doParse(component, s string) (*Path, error) {
+	p := &Path{
+		component:             component,
+		posContainerLow:       -1,
+		posContainerHigh:      -1,
+		posSectionHigh:        -1,
+		posIdentifierLanguage: -1,
+	}
+
+	hasLang := pp.LanguageIndex != nil
+	hasLang = hasLang && (component == files.ComponentFolderContent || component == files.ComponentFolderLayouts)
+
+	if runtime.GOOS == "windows" {
+		s = path.Clean(filepath.ToSlash(s))
+		if s == "." {
+			s = ""
+		}
+	}
+
+	if s == "" {
+		s = "/"
+	}
+
+	// Leading slash, no trailing slash.
+	if !strings.HasPrefix(s, "/") {
+		s = "/" + s
+	}
+
+	if s != "/" && s[len(s)-1] == '/' {
+		s = s[:len(s)-1]
+	}
+
+	p.s = s
+	slashCount := 0
+
+	for i := len(s) - 1; i >= 0; i-- {
+		c := s[i]
+
+		switch c {
+		case '.':
+			if p.posContainerHigh == -1 {
+				var high int
+				if len(p.identifiers) > 0 {
+					high = p.identifiers[len(p.identifiers)-1].Low - 1
+				} else {
+					high = len(p.s)
+				}
+				id := types.LowHigh{Low: i + 1, High: high}
+				if len(p.identifiers) == 0 {
+					p.identifiers = append(p.identifiers, id)
+				} else if len(p.identifiers) == 1 {
+					// Check for a valid language.
+					s := p.s[id.Low:id.High]
+
+					if hasLang {
+						var disabled bool
+						_, langFound := pp.LanguageIndex[s]
+						if !langFound {
+							disabled = pp.IsLangDisabled != nil && pp.IsLangDisabled(s)
+							if disabled {
+								p.disabled = true
+								langFound = true
+							}
+						}
+						if langFound {
+							p.posIdentifierLanguage = 1
+							p.identifiers = append(p.identifiers, id)
+						}
+					}
+				}
+			}
+		case '/':
+			slashCount++
+			if p.posContainerHigh == -1 {
+				p.posContainerHigh = i + 1
+			} else if p.posContainerLow == -1 {
+				p.posContainerLow = i + 1
+			}
+			if i > 0 {
+				p.posSectionHigh = i
+			}
+		}
+	}
+
+	isContentComponent := p.component == files.ComponentFolderContent || p.component == files.ComponentFolderArchetypes
+	isContent := isContentComponent && files.IsContentExt(p.Ext())
+
+	if isContent {
+		id := p.identifiers[len(p.identifiers)-1]
+		b := p.s[p.posContainerHigh : id.Low-1]
+		switch b {
+		case "index":
+			p.bundleType = PathTypeLeaf
+		case "_index":
+			p.bundleType = PathTypeBranch
+		default:
+			p.bundleType = PathTypeContentSingle
+		}
+
+		if slashCount == 2 && p.IsLeafBundle() {
+			p.posSectionHigh = 0
+		}
+	}
+
+	return p, nil
+}
+
+func ModifyPathBundleTypeResource(p *Path) {
+	if p.IsContent() {
+		p.bundleType = PathTypeContentResource
+	} else {
+		p.bundleType = PathTypeFile
+	}
+}
+
+type PathType int
+
+const (
+	// A generic resource, e.g. a JSON file.
+	PathTypeFile PathType = iota
+
+	// All below are content files.
+	// A resource of a content type with front matter.
+	PathTypeContentResource
+
+	// E.g. /blog/my-post.md
+	PathTypeContentSingle
+
+	// All bewlow are bundled content files.
+
+	// Leaf bundles, e.g. /blog/my-post/index.md
+	PathTypeLeaf
+
+	// Branch bundles, e.g. /blog/_index.md
+	PathTypeBranch
+)
+
+type Path struct {
+	s string
+
+	posContainerLow  int
+	posContainerHigh int
+	posSectionHigh   int
+
+	component  string
+	bundleType PathType
+
+	identifiers []types.LowHigh
+
+	posIdentifierLanguage int
+	disabled              bool
+
+	trimLeadingSlash bool
+
+	unnormalized *Path
+}
+
+// TrimLeadingSlash returns a copy of the Path with the leading slash removed.
+func (p Path) TrimLeadingSlash() *Path {
+	p.trimLeadingSlash = true
+	return &p
+}
+
+func (p *Path) norm(s string) string {
+	if p.trimLeadingSlash {
+		s = strings.TrimPrefix(s, "/")
+	}
+	return s
+}
+
+// IdentifierBase satifies identity.Identity.
+func (p *Path) IdentifierBase() string {
+	return p.Base()[1:]
+}
+
+// Component returns the component for this path (e.g. "content").
+func (p *Path) Component() string {
+	return p.component
+}
+
+// Container returns the base name of the container directory for this path.
+func (p *Path) Container() string {
+	if p.posContainerLow == -1 {
+		return ""
+	}
+	return p.norm(p.s[p.posContainerLow : p.posContainerHigh-1])
+}
+
+// ContainerDir returns the container directory for this path.
+// For content bundles this will be the parent directory.
+func (p *Path) ContainerDir() string {
+	if p.posContainerLow == -1 || !p.IsBundle() {
+		return p.Dir()
+	}
+	return p.norm(p.s[:p.posContainerLow-1])
+}
+
+// Section returns the first path element (section).
+func (p *Path) Section() string {
+	if p.posSectionHigh <= 0 {
+		return ""
+	}
+	return p.norm(p.s[1:p.posSectionHigh])
+}
+
+// IsContent returns true if the path is a content file (e.g. mypost.md).
+// Note that this will also return true for content files in a bundle.
+func (p *Path) IsContent() bool {
+	return p.BundleType() >= PathTypeContentResource
+}
+
+// isContentPage returns true if the path is a content file (e.g. mypost.md),
+// but nof if inside a leaf bundle.
+func (p *Path) isContentPage() bool {
+	return p.BundleType() >= PathTypeContentSingle
+}
+
+// Name returns the last element of path.
+func (p *Path) Name() string {
+	if p.posContainerHigh > 0 {
+		return p.s[p.posContainerHigh:]
+	}
+	return p.s
+}
+
+// Name returns the last element of path withhout any extension.
+func (p *Path) NameNoExt() string {
+	if i := p.identifierIndex(0); i != -1 {
+		return p.s[p.posContainerHigh : p.identifiers[i].Low-1]
+	}
+	return p.s[p.posContainerHigh:]
+}
+
+// Name returns the last element of path withhout any language identifier.
+func (p *Path) NameNoLang() string {
+	i := p.identifierIndex(p.posIdentifierLanguage)
+	if i == -1 {
+		return p.Name()
+	}
+
+	return p.s[p.posContainerHigh:p.identifiers[i].Low-1] + p.s[p.identifiers[i].High:]
+}
+
+// BaseNameNoIdentifier returns the logcical base name for a resource without any idenifier (e.g. no extension).
+// For bundles this will be the containing directory's name, e.g. "blog".
+func (p *Path) BaseNameNoIdentifier() string {
+	if p.IsBundle() {
+		return p.Container()
+	}
+	return p.NameNoIdentifier()
+}
+
+// NameNoIdentifier returns the last element of path withhout any identifier (e.g. no extension).
+func (p *Path) NameNoIdentifier() string {
+	if len(p.identifiers) > 0 {
+		return p.s[p.posContainerHigh : p.identifiers[len(p.identifiers)-1].Low-1]
+	}
+	return p.s[p.posContainerHigh:]
+}
+
+// Dir returns all but the last element of path, typically the path's directory.
+func (p *Path) Dir() (d string) {
+	if p.posContainerHigh > 0 {
+		d = p.s[:p.posContainerHigh-1]
+	}
+	if d == "" {
+		d = "/"
+	}
+	d = p.norm(d)
+	return
+}
+
+// Path returns the full path.
+func (p *Path) Path() (d string) {
+	return p.norm(p.s)
+}
+
+// Unnormalized returns the Path with the original case preserved.
+func (p *Path) Unnormalized() *Path {
+	return p.unnormalized
+}
+
+// PathNoLang returns the Path but with any language identifier removed.
+func (p *Path) PathNoLang() string {
+	return p.base(true, false)
+}
+
+// PathNoIdentifier returns the Path but with any identifier (ext, lang) removed.
+func (p *Path) PathNoIdentifier() string {
+	return p.base(false, false)
+}
+
+// PathRel returns the path relativeto the given owner.
+func (p *Path) PathRel(owner *Path) string {
+	ob := owner.Base()
+	if !strings.HasSuffix(ob, "/") {
+		ob += "/"
+	}
+	return strings.TrimPrefix(p.Path(), ob)
+}
+
+// BaseRel returns the base path relative to the given owner.
+func (p *Path) BaseRel(owner *Path) string {
+	ob := owner.Base()
+	if ob == "/" {
+		ob = ""
+	}
+	return p.Base()[len(ob)+1:]
+}
+
+// For content files, Base returns the path without any identifiers (extension, language code etc.).
+// Any 'index' as the last path element is ignored.
+//
+// For other files (Resources), any extension is kept.
+func (p *Path) Base() string {
+	return p.base(!p.isContentPage(), p.IsBundle())
+}
+
+// BaseNoLeadingSlash returns the base path without the leading slash.
+func (p *Path) BaseNoLeadingSlash() string {
+	return p.Base()[1:]
+}
+
+func (p *Path) base(preserveExt, isBundle bool) string {
+	if len(p.identifiers) == 0 {
+		return p.norm(p.s)
+	}
+
+	if preserveExt && len(p.identifiers) == 1 {
+		// Preserve extension.
+		return p.norm(p.s)
+	}
+
+	id := p.identifiers[len(p.identifiers)-1]
+	high := id.Low - 1
+
+	if isBundle {
+		high = p.posContainerHigh - 1
+	}
+
+	if high == 0 {
+		high++
+	}
+
+	if !preserveExt {
+		return p.norm(p.s[:high])
+	}
+
+	// For txt files etc. we want to preserve the extension.
+	id = p.identifiers[0]
+
+	return p.norm(p.s[:high] + p.s[id.Low-1:id.High])
+}
+
+func (p *Path) Ext() string {
+	return p.identifierAsString(0)
+}
+
+func (p *Path) Lang() string {
+	return p.identifierAsString(1)
+}
+
+func (p *Path) Identifier(i int) string {
+	return p.identifierAsString(i)
+}
+
+func (p *Path) Disabled() bool {
+	return p.disabled
+}
+
+func (p *Path) Identifiers() []string {
+	ids := make([]string, len(p.identifiers))
+	for i, id := range p.identifiers {
+		ids[i] = p.s[id.Low:id.High]
+	}
+	return ids
+}
+
+func (p *Path) IsHTML() bool {
+	return files.IsHTML(p.Ext())
+}
+
+func (p *Path) BundleType() PathType {
+	return p.bundleType
+}
+
+func (p *Path) IsBundle() bool {
+	return p.bundleType >= PathTypeLeaf
+}
+
+func (p *Path) IsBranchBundle() bool {
+	return p.bundleType == PathTypeBranch
+}
+
+func (p *Path) IsLeafBundle() bool {
+	return p.bundleType == PathTypeLeaf
+}
+
+func (p *Path) identifierAsString(i int) string {
+	i = p.identifierIndex(i)
+	if i == -1 {
+		return ""
+	}
+
+	id := p.identifiers[i]
+	return p.s[id.Low:id.High]
+}
+
+func (p *Path) identifierIndex(i int) int {
+	if i < 0 || i >= len(p.identifiers) {
+		return -1
+	}
+	return i
+}
+
+// HasExt returns true if the Unix styled path has an extension.
+func HasExt(p string) bool {
+	for i := len(p) - 1; i >= 0; i-- {
+		if p[i] == '.' {
+			return true
+		}
+		if p[i] == '/' {
+			return false
+		}
+	}
+	return false
+}

common/paths/pathparser_test.go

@@ -0,0 +1,351 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package paths
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/gohugoio/hugo/hugofs/files"
+
+	qt "github.com/frankban/quicktest"
+)
+
+var testParser = &PathParser{
+	LanguageIndex: map[string]int{
+		"no": 0,
+		"en": 1,
+	},
+}
+
+func TestParse(t *testing.T) {
+	c := qt.New(t)
+
+	tests := []struct {
+		name   string
+		path   string
+		assert func(c *qt.C, p *Path)
+	}{
+		{
+			"Basic text file",
+			"/a/b.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Name(), qt.Equals, "b.txt")
+				c.Assert(p.Base(), qt.Equals, "/a/b.txt")
+				c.Assert(p.Container(), qt.Equals, "a")
+				c.Assert(p.Dir(), qt.Equals, "/a")
+				c.Assert(p.Ext(), qt.Equals, "txt")
+				c.Assert(p.IsContent(), qt.IsFalse)
+			},
+		},
+		{
+			"Basic text file, upper case",
+			"/A/B.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Name(), qt.Equals, "b.txt")
+				c.Assert(p.NameNoExt(), qt.Equals, "b")
+				c.Assert(p.NameNoIdentifier(), qt.Equals, "b")
+				c.Assert(p.BaseNameNoIdentifier(), qt.Equals, "b")
+				c.Assert(p.Base(), qt.Equals, "/a/b.txt")
+				c.Assert(p.Ext(), qt.Equals, "txt")
+			},
+		},
+		{
+			"Basic text file, 1 space in dir",
+			"/a b/c.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a-b/c.txt")
+			},
+		},
+		{
+			"Basic text file, 2 spaces in dir",
+			"/a  b/c.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a--b/c.txt")
+			},
+		},
+		{
+			"Basic text file, 1 space in filename",
+			"/a/b c.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a/b-c.txt")
+			},
+		},
+		{
+			"Basic text file, 2 spaces in filename",
+			"/a/b  c.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a/b--c.txt")
+			},
+		},
+		{
+			"Basic text file, mixed case and spaces, unnormalized",
+			"/a/Foo BAR.txt",
+			func(c *qt.C, p *Path) {
+				pp := p.Unnormalized()
+				c.Assert(pp, qt.IsNotNil)
+				c.Assert(pp.BaseNameNoIdentifier(), qt.Equals, "Foo BAR")
+			},
+		},
+		{
+			"Basic Markdown file",
+			"/a/b/c.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.IsContent(), qt.IsTrue)
+				c.Assert(p.IsLeafBundle(), qt.IsFalse)
+				c.Assert(p.Name(), qt.Equals, "c.md")
+				c.Assert(p.Base(), qt.Equals, "/a/b/c")
+				c.Assert(p.Section(), qt.Equals, "a")
+				c.Assert(p.BaseNameNoIdentifier(), qt.Equals, "c")
+				c.Assert(p.Path(), qt.Equals, "/a/b/c.md")
+				c.Assert(p.Dir(), qt.Equals, "/a/b")
+				c.Assert(p.Container(), qt.Equals, "b")
+				c.Assert(p.ContainerDir(), qt.Equals, "/a/b")
+				c.Assert(p.Ext(), qt.Equals, "md")
+			},
+		},
+		{
+			"Content resource",
+			"/a/b.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Name(), qt.Equals, "b.md")
+				c.Assert(p.Base(), qt.Equals, "/a/b")
+				c.Assert(p.BaseNoLeadingSlash(), qt.Equals, "a/b")
+				c.Assert(p.Section(), qt.Equals, "a")
+				c.Assert(p.BaseNameNoIdentifier(), qt.Equals, "b")
+
+				// Reclassify it as a content resource.
+				ModifyPathBundleTypeResource(p)
+				c.Assert(p.BundleType(), qt.Equals, PathTypeContentResource)
+				c.Assert(p.IsContent(), qt.IsTrue)
+				c.Assert(p.Name(), qt.Equals, "b.md")
+				c.Assert(p.Base(), qt.Equals, "/a/b.md")
+			},
+		},
+		{
+			"No ext",
+			"/a/b",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Name(), qt.Equals, "b")
+				c.Assert(p.NameNoExt(), qt.Equals, "b")
+				c.Assert(p.Base(), qt.Equals, "/a/b")
+				c.Assert(p.Ext(), qt.Equals, "")
+			},
+		},
+		{
+			"No ext, trailing slash",
+			"/a/b/",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Name(), qt.Equals, "b")
+				c.Assert(p.Base(), qt.Equals, "/a/b")
+				c.Assert(p.Ext(), qt.Equals, "")
+			},
+		},
+		{
+			"Identifiers",
+			"/a/b.a.b.no.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Name(), qt.Equals, "b.a.b.no.txt")
+				c.Assert(p.NameNoIdentifier(), qt.Equals, "b.a.b")
+				c.Assert(p.NameNoLang(), qt.Equals, "b.a.b.txt")
+				c.Assert(p.Identifiers(), qt.DeepEquals, []string{"txt", "no"})
+				c.Assert(p.Base(), qt.Equals, "/a/b.a.b.txt")
+				c.Assert(p.BaseNoLeadingSlash(), qt.Equals, "a/b.a.b.txt")
+				c.Assert(p.PathNoLang(), qt.Equals, "/a/b.a.b.txt")
+				c.Assert(p.Ext(), qt.Equals, "txt")
+				c.Assert(p.PathNoIdentifier(), qt.Equals, "/a/b.a.b")
+			},
+		},
+		{
+			"Home branch cundle",
+			"/_index.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/")
+				c.Assert(p.Path(), qt.Equals, "/_index.md")
+				c.Assert(p.Container(), qt.Equals, "")
+				c.Assert(p.ContainerDir(), qt.Equals, "/")
+			},
+		},
+		{
+			"Index content file in root",
+			"/a/index.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a")
+				c.Assert(p.BaseNameNoIdentifier(), qt.Equals, "a")
+				c.Assert(p.Container(), qt.Equals, "a")
+				c.Assert(p.Container(), qt.Equals, "a")
+				c.Assert(p.ContainerDir(), qt.Equals, "")
+				c.Assert(p.Dir(), qt.Equals, "/a")
+				c.Assert(p.Ext(), qt.Equals, "md")
+				c.Assert(p.Identifiers(), qt.DeepEquals, []string{"md"})
+				c.Assert(p.IsBranchBundle(), qt.IsFalse)
+				c.Assert(p.IsBundle(), qt.IsTrue)
+				c.Assert(p.IsLeafBundle(), qt.IsTrue)
+				c.Assert(p.Lang(), qt.Equals, "")
+				c.Assert(p.NameNoExt(), qt.Equals, "index")
+				c.Assert(p.NameNoIdentifier(), qt.Equals, "index")
+				c.Assert(p.NameNoLang(), qt.Equals, "index.md")
+				c.Assert(p.Section(), qt.Equals, "")
+			},
+		},
+		{
+			"Index content file with lang",
+			"/a/b/index.no.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a/b")
+				c.Assert(p.BaseNameNoIdentifier(), qt.Equals, "b")
+				c.Assert(p.Container(), qt.Equals, "b")
+				c.Assert(p.ContainerDir(), qt.Equals, "/a")
+				c.Assert(p.Dir(), qt.Equals, "/a/b")
+				c.Assert(p.Ext(), qt.Equals, "md")
+				c.Assert(p.Identifiers(), qt.DeepEquals, []string{"md", "no"})
+				c.Assert(p.IsBranchBundle(), qt.IsFalse)
+				c.Assert(p.IsBundle(), qt.IsTrue)
+				c.Assert(p.IsLeafBundle(), qt.IsTrue)
+				c.Assert(p.Lang(), qt.Equals, "no")
+				c.Assert(p.NameNoExt(), qt.Equals, "index.no")
+				c.Assert(p.NameNoIdentifier(), qt.Equals, "index")
+				c.Assert(p.NameNoLang(), qt.Equals, "index.md")
+				c.Assert(p.PathNoLang(), qt.Equals, "/a/b/index.md")
+				c.Assert(p.Section(), qt.Equals, "a")
+			},
+		},
+		{
+			"Index branch content file",
+			"/a/b/_index.no.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a/b")
+				c.Assert(p.BaseNameNoIdentifier(), qt.Equals, "b")
+				c.Assert(p.Container(), qt.Equals, "b")
+				c.Assert(p.ContainerDir(), qt.Equals, "/a")
+				c.Assert(p.Ext(), qt.Equals, "md")
+				c.Assert(p.Identifiers(), qt.DeepEquals, []string{"md", "no"})
+				c.Assert(p.IsBranchBundle(), qt.IsTrue)
+				c.Assert(p.IsBundle(), qt.IsTrue)
+				c.Assert(p.IsLeafBundle(), qt.IsFalse)
+				c.Assert(p.NameNoExt(), qt.Equals, "_index.no")
+				c.Assert(p.NameNoLang(), qt.Equals, "_index.md")
+			},
+		},
+		{
+			"Index root no slash",
+			"_index.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/")
+				c.Assert(p.Ext(), qt.Equals, "md")
+				c.Assert(p.Name(), qt.Equals, "_index.md")
+			},
+		},
+		{
+			"Index root",
+			"/_index.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/")
+				c.Assert(p.Ext(), qt.Equals, "md")
+				c.Assert(p.Name(), qt.Equals, "_index.md")
+			},
+		},
+		{
+			"Index first",
+			"/a/_index.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Section(), qt.Equals, "a")
+			},
+		},
+		{
+			"Index text file",
+			"/a/b/index.no.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a/b/index.txt")
+				c.Assert(p.Ext(), qt.Equals, "txt")
+				c.Assert(p.Identifiers(), qt.DeepEquals, []string{"txt", "no"})
+				c.Assert(p.IsLeafBundle(), qt.IsFalse)
+				c.Assert(p.PathNoIdentifier(), qt.Equals, "/a/b/index")
+			},
+		},
+		{
+			"Empty",
+			"",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/")
+				c.Assert(p.Ext(), qt.Equals, "")
+				c.Assert(p.Name(), qt.Equals, "")
+				c.Assert(p.Path(), qt.Equals, "/")
+			},
+		},
+		{
+			"Slash",
+			"/",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/")
+				c.Assert(p.Ext(), qt.Equals, "")
+				c.Assert(p.Name(), qt.Equals, "")
+			},
+		},
+		{
+			"Trim Leading Slash bundle",
+			"foo/bar/index.no.md",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Path(), qt.Equals, "/foo/bar/index.no.md")
+				pp := p.TrimLeadingSlash()
+				c.Assert(pp.Path(), qt.Equals, "foo/bar/index.no.md")
+				c.Assert(pp.PathNoLang(), qt.Equals, "foo/bar/index.md")
+				c.Assert(pp.Base(), qt.Equals, "foo/bar")
+				c.Assert(pp.Dir(), qt.Equals, "foo/bar")
+				c.Assert(pp.ContainerDir(), qt.Equals, "foo")
+				c.Assert(pp.Container(), qt.Equals, "bar")
+				c.Assert(pp.BaseNameNoIdentifier(), qt.Equals, "bar")
+			},
+		},
+		{
+			"Trim Leading Slash file",
+			"foo/bar.txt",
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Path(), qt.Equals, "/foo/bar.txt")
+				pp := p.TrimLeadingSlash()
+				c.Assert(pp.Path(), qt.Equals, "foo/bar.txt")
+				c.Assert(pp.PathNoLang(), qt.Equals, "foo/bar.txt")
+				c.Assert(pp.Base(), qt.Equals, "foo/bar.txt")
+				c.Assert(pp.Dir(), qt.Equals, "foo")
+				c.Assert(pp.ContainerDir(), qt.Equals, "foo")
+				c.Assert(pp.Container(), qt.Equals, "foo")
+				c.Assert(pp.BaseNameNoIdentifier(), qt.Equals, "bar")
+			},
+		},
+		{
+			"File separator",
+			filepath.FromSlash("/a/b/c.txt"),
+			func(c *qt.C, p *Path) {
+				c.Assert(p.Base(), qt.Equals, "/a/b/c.txt")
+				c.Assert(p.Ext(), qt.Equals, "txt")
+				c.Assert(p.Name(), qt.Equals, "c.txt")
+				c.Assert(p.Path(), qt.Equals, "/a/b/c.txt")
+			},
+		},
+	}
+	for _, test := range tests {
+		c.Run(test.name, func(c *qt.C) {
+			test.assert(c, testParser.Parse(files.ComponentFolderContent, test.path))
+		})
+	}
+}
+
+func TestHasExt(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(HasExt("/a/b/c.txt"), qt.IsTrue)
+	c.Assert(HasExt("/a/b.c/d.txt"), qt.IsTrue)
+	c.Assert(HasExt("/a/b/c"), qt.IsFalse)
+	c.Assert(HasExt("/a/b.c/d"), qt.IsFalse)
+}

common/paths/paths_integration_test.go

@@ -0,0 +1,80 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package paths_test
+
+import (
+	"testing"
+
+	"github.com/gohugoio/hugo/hugolib"
+)
+
+func TestRemovePathAccents(t *testing.T) {
+	t.Parallel()
+
+	files := `
+-- hugo.toml --
+disableKinds = ["taxonomy", "term"]
+defaultContentLanguage = "en"
+defaultContentLanguageInSubdir = true
+[languages]
+[languages.en]
+weight = 1
+[languages.fr]
+weight = 2
+removePathAccents = true
+-- content/διακριτικός.md --
+-- content/διακριτικός.fr.md --
+-- layouts/_default/single.html --
+{{ .Language.Lang }}|Single.
+-- layouts/_default/list.html --
+List
+`
+	b := hugolib.Test(t, files)
+
+	b.AssertFileContent("public/en/διακριτικός/index.html", "en|Single")
+	b.AssertFileContent("public/fr/διακριτικος/index.html", "fr|Single")
+}
+
+func TestDisablePathToLower(t *testing.T) {
+	t.Parallel()
+
+	files := `
+-- hugo.toml --
+disableKinds = ["taxonomy", "term"]
+defaultContentLanguage = "en"
+defaultContentLanguageInSubdir = true
+[languages]
+[languages.en]
+weight = 1
+[languages.fr]
+weight = 2
+disablePathToLower = true
+-- content/MySection/MyPage.md --
+-- content/MySection/MyPage.fr.md --
+-- content/MySection/MyBundle/index.md --
+-- content/MySection/MyBundle/index.fr.md --
+-- layouts/_default/single.html --
+{{ .Language.Lang }}|Single.
+-- layouts/_default/list.html --
+{{ .Language.Lang }}|List.
+`
+	b := hugolib.Test(t, files)
+
+	b.AssertFileContent("public/en/mysection/index.html", "en|List")
+	b.AssertFileContent("public/en/mysection/mypage/index.html", "en|Single")
+	b.AssertFileContent("public/fr/MySection/index.html", "fr|List")
+	b.AssertFileContent("public/fr/MySection/MyPage/index.html", "fr|Single")
+	b.AssertFileContent("public/en/mysection/mybundle/index.html", "en|Single")
+	b.AssertFileContent("public/fr/MySection/MyBundle/index.html", "fr|Single")
+}

common/paths/pathtype_string.go

@@ -0,0 +1,27 @@
+// Code generated by "stringer -type=PathType"; DO NOT EDIT.
+
+package paths
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[PathTypeFile-0]
+	_ = x[PathTypeContentResource-1]
+	_ = x[PathTypeContentSingle-2]
+	_ = x[PathTypeLeaf-3]
+	_ = x[PathTypeBranch-4]
+}
+
+const _PathType_name = "PathTypeFilePathTypeContentResourcePathTypeContentSinglePathTypeLeafPathTypeBranch"
+
+var _PathType_index = [...]uint8{0, 12, 35, 56, 68, 82}
+
+func (i PathType) String() string {
+	if i < 0 || i >= PathType(len(_PathType_index)-1) {
+		return "PathType(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _PathType_name[_PathType_index[i]:_PathType_index[i+1]]
+}

common/paths/url.go

@@ -51,9 +51,10 @@ var pb pathBridge
 
 // MakePermalink combines base URL with content path to create full URL paths.
 // Example
-//    base:   http://spf13.com/
-//    path:   post/how-i-blog
-//    result: http://spf13.com/post/how-i-blog
+//
+//	base:   http://spf13.com/
+//	path:   post/how-i-blog
+//	result: http://spf13.com/post/how-i-blog
 func MakePermalink(host, plink string) *url.URL {
 	base, err := url.Parse(host)
 	if err != nil {
@@ -70,6 +71,8 @@ func MakePermalink(host, plink string) *url.URL {
 	}
 
 	base.Path = path.Join(base.Path, p.Path)
+	base.Fragment = p.Fragment
+	base.RawQuery = p.RawQuery
 
 	// path.Join will strip off the last /, so put it back if it was there.
 	hadTrailingSlash := (plink == "" && strings.HasSuffix(host, "/")) || strings.HasSuffix(p.Path, "/")
@@ -117,17 +120,19 @@ func PrettifyURL(in string) string {
 
 // PrettifyURLPath takes a URL path to a content and converts it
 // to enable pretty URLs.
-//     /section/name.html       becomes /section/name/index.html
-//     /section/name/           becomes /section/name/index.html
-//     /section/name/index.html becomes /section/name/index.html
+//
+//	/section/name.html       becomes /section/name/index.html
+//	/section/name/           becomes /section/name/index.html
+//	/section/name/index.html becomes /section/name/index.html
 func PrettifyURLPath(in string) string {
 	return prettifyPath(in, pb)
 }
 
 // Uglify does the opposite of PrettifyURLPath().
-//     /section/name/index.html becomes /section/name.html
-//     /section/name/           becomes /section/name.html
-//     /section/name.html       becomes /section/name.html
+//
+//	/section/name/index.html becomes /section/name.html
+//	/section/name/           becomes /section/name.html
+//	/section/name.html       becomes /section/name.html
 func Uglify(in string) string {
 	if path.Ext(in) == "" {
 		if len(in) < 2 {
@@ -158,7 +163,6 @@ func Uglify(in string) string {
 // If ParseRequestURI fails, the input is just converted to OS specific slashes and returned.
 func UrlToFilename(s string) (string, bool) {
 	u, err := url.ParseRequestURI(s)
-
 	if err != nil {
 		return filepath.FromSlash(s), false
 	}
@@ -179,3 +183,13 @@ func UrlToFilename(s string) (string, bool) {
 
 	return p, true
 }
+
+// URLEscape escapes unicode letters.
+func URLEscape(uri string) string {
+	// escape unicode letters
+	u, err := url.Parse(uri)
+	if err != nil {
+		panic(err)
+	}
+	return u.String()
+}

common/paths/url_test.go

@@ -31,6 +31,7 @@ func TestMakePermalink(t *testing.T) {
 		{"http://abc.com", "bar", "http://abc.com/bar"},
 		{"http://abc.com/foo/bar", "post/bar", "http://abc.com/foo/bar/post/bar"},
 		{"http://abc.com/foo/bar", "post/bar/", "http://abc.com/foo/bar/post/bar/"},
+		{"http://abc.com/foo", "post/bar?a=b#c", "http://abc.com/foo/post/bar?a=b#c"},
 	}
 
 	for i, d := range data {

common/predicate/predicate.go

@@ -0,0 +1,72 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package predicate
+
+// P is a predicate function that tests whether a value of type T satisfies some condition.
+type P[T any] func(T) bool
+
+// And returns a predicate that is a short-circuiting logical AND of this and the given predicates.
+func (p P[T]) And(ps ...P[T]) P[T] {
+	return func(v T) bool {
+		for _, pp := range ps {
+			if !pp(v) {
+				return false
+			}
+		}
+		return p(v)
+	}
+}
+
+// Or returns a predicate that is a short-circuiting logical OR of this and the given predicates.
+func (p P[T]) Or(ps ...P[T]) P[T] {
+	return func(v T) bool {
+		for _, pp := range ps {
+			if pp(v) {
+				return true
+			}
+		}
+		return p(v)
+	}
+}
+
+// Negate returns a predicate that is a logical negation of this predicate.
+func (p P[T]) Negate() P[T] {
+	return func(v T) bool {
+		return !p(v)
+	}
+}
+
+// Filter returns a new slice holding only the elements of s that satisfy p.
+// Filter modifies the contents of the slice s and returns the modified slice, which may have a smaller length.
+func (p P[T]) Filter(s []T) []T {
+	var n int
+	for _, v := range s {
+		if p(v) {
+			s[n] = v
+			n++
+		}
+	}
+	return s[:n]
+}
+
+// FilterCopy returns a new slice holding only the elements of s that satisfy p.
+func (p P[T]) FilterCopy(s []T) []T {
+	var result []T
+	for _, v := range s {
+		if p(v) {
+			result = append(result, v)
+		}
+	}
+	return result
+}

common/predicate/predicate_test.go

@@ -0,0 +1,83 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package predicate_test
+
+import (
+	"testing"
+
+	qt "github.com/frankban/quicktest"
+	"github.com/gohugoio/hugo/common/predicate"
+)
+
+func TestAdd(t *testing.T) {
+	c := qt.New(t)
+
+	var p predicate.P[int] = intP1
+
+	c.Assert(p(1), qt.IsTrue)
+	c.Assert(p(2), qt.IsFalse)
+
+	neg := p.Negate()
+	c.Assert(neg(1), qt.IsFalse)
+	c.Assert(neg(2), qt.IsTrue)
+
+	and := p.And(intP2)
+	c.Assert(and(1), qt.IsFalse)
+	c.Assert(and(2), qt.IsFalse)
+	c.Assert(and(10), qt.IsTrue)
+
+	or := p.Or(intP2)
+	c.Assert(or(1), qt.IsTrue)
+	c.Assert(or(2), qt.IsTrue)
+	c.Assert(or(10), qt.IsTrue)
+	c.Assert(or(11), qt.IsFalse)
+}
+
+func TestFilter(t *testing.T) {
+	c := qt.New(t)
+
+	var p predicate.P[int] = intP1
+	p = p.Or(intP2)
+
+	ints := []int{1, 2, 3, 4, 1, 6, 7, 8, 2}
+
+	c.Assert(p.Filter(ints), qt.DeepEquals, []int{1, 2, 1, 2})
+	c.Assert(ints, qt.DeepEquals, []int{1, 2, 1, 2, 1, 6, 7, 8, 2})
+}
+
+func TestFilterCopy(t *testing.T) {
+	c := qt.New(t)
+
+	var p predicate.P[int] = intP1
+	p = p.Or(intP2)
+
+	ints := []int{1, 2, 3, 4, 1, 6, 7, 8, 2}
+
+	c.Assert(p.FilterCopy(ints), qt.DeepEquals, []int{1, 2, 1, 2})
+	c.Assert(ints, qt.DeepEquals, []int{1, 2, 3, 4, 1, 6, 7, 8, 2})
+}
+
+var intP1 = func(i int) bool {
+	if i == 10 {
+		return true
+	}
+	return i == 1
+}
+
+var intP2 = func(i int) bool {
+	if i == 10 {
+		return true
+	}
+	return i == 2
+}

common/rungroup/rungroup.go

@@ -0,0 +1,93 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package rungroup
+
+import (
+	"context"
+
+	"golang.org/x/sync/errgroup"
+)
+
+// Group is a group of workers that can be used to enqueue work and wait for
+// them to finish.
+type Group[T any] interface {
+	Enqueue(T) error
+	Wait() error
+}
+
+type runGroup[T any] struct {
+	ctx context.Context
+	g   *errgroup.Group
+	ch  chan T
+}
+
+// Config is the configuration for a new Group.
+type Config[T any] struct {
+	NumWorkers int
+	Handle     func(context.Context, T) error
+}
+
+// Run creates a new Group with the given configuration.
+func Run[T any](ctx context.Context, cfg Config[T]) Group[T] {
+	if cfg.NumWorkers <= 0 {
+		cfg.NumWorkers = 1
+	}
+	if cfg.Handle == nil {
+		panic("Handle must be set")
+	}
+
+	g, ctx := errgroup.WithContext(ctx)
+	// Buffered for performance.
+	ch := make(chan T, cfg.NumWorkers)
+
+	for i := 0; i < cfg.NumWorkers; i++ {
+		g.Go(func() error {
+			for {
+				select {
+				case <-ctx.Done():
+					return nil
+				case v, ok := <-ch:
+					if !ok {
+						return nil
+					}
+					if err := cfg.Handle(ctx, v); err != nil {
+						return err
+					}
+				}
+			}
+		})
+	}
+
+	return &runGroup[T]{
+		ctx: ctx,
+		g:   g,
+		ch:  ch,
+	}
+}
+
+// Enqueue enqueues a new item to be handled by the workers.
+func (r *runGroup[T]) Enqueue(t T) error {
+	select {
+	case <-r.ctx.Done():
+		return nil
+	case r.ch <- t:
+	}
+	return nil
+}
+
+// Wait waits for all workers to finish and returns the first error.
+func (r *runGroup[T]) Wait() error {
+	close(r.ch)
+	return r.g.Wait()
+}

common/rungroup/rungroup_test.go

@@ -0,0 +1,44 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package rungroup
+
+import (
+	"context"
+	"testing"
+
+	qt "github.com/frankban/quicktest"
+)
+
+func TestNew(t *testing.T) {
+	c := qt.New(t)
+
+	var result int
+	adder := func(ctx context.Context, i int) error {
+		result += i
+		return nil
+	}
+
+	g := Run[int](
+		context.Background(),
+		Config[int]{
+			Handle: adder,
+		},
+	)
+
+	c.Assert(g, qt.IsNotNil)
+	g.Enqueue(32)
+	g.Enqueue(33)
+	c.Assert(g.Wait(), qt.IsNil)
+	c.Assert(result, qt.Equals, 65)
+}

common/terminal/colors.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/text/transform.go

@@ -23,6 +23,64 @@ import (
 	"golang.org/x/text/unicode/norm"
 )
 
+var transliteratePool = &sync.Pool{
+	New: func() any {
+		return transform.Chain(norm.NFD, runes.Remove(runes.In(unicode.Mn)),
+			runes.Map(func(r rune) rune {
+				switch r {
+				case 'ą':
+					return 'a'
+				case 'ć':
+					return 'c'
+				case 'ę':
+					return 'e'
+				case 'ł':
+					return 'l'
+				case 'ń':
+					return 'n'
+				case 'ó':
+					return 'o'
+				case 'ś':
+					return 's'
+				case 'ż':
+					return 'z'
+				case 'ź':
+					return 'z'
+				case 'ø':
+					return 'o'
+				}
+				return r
+			}),
+			norm.NFC)
+	},
+}
+
+var transliterateMap = map[rune]rune{
+	'ą': 'a',
+	'ć': 'c',
+	'ę': 'e',
+	'ł': 'l',
+	'ń': 'n',
+	'ó': 'o',
+	'ś': 's',
+	'ż': 'z',
+	'ź': 'z',
+	'ø': 'o',
+}
+
+var transliteratePoolMap = &sync.Pool{
+	New: func() any {
+		return transform.Chain(norm.NFD, runes.Remove(runes.In(unicode.Mn)),
+			runes.Map(func(r rune) rune {
+				if rr, ok := transliterateMap[r]; ok {
+					return rr
+				}
+				return r
+			}),
+			norm.NFC)
+	},
+}
+
 var accentTransformerPool = &sync.Pool{
 	New: func() any {
 		return transform.Chain(norm.NFD, runes.Remove(runes.In(unicode.Mn)), norm.NFC)
@@ -47,6 +105,22 @@ func RemoveAccentsString(s string) string {
 	return s
 }
 
+func TransliterateString(s string) string {
+	t := transliteratePool.Get().(transform.Transformer)
+	s, _, _ = transform.String(t, s)
+	t.Reset()
+	transliteratePool.Put(t)
+	return s
+}
+
+func TransliterateStringMap(s string) string {
+	t := transliteratePoolMap.Get().(transform.Transformer)
+	s, _, _ = transform.String(t, s)
+	t.Reset()
+	transliteratePoolMap.Put(t)
+	return s
+}
+
 // Chomp removes trailing newline characters from s.
 func Chomp(s string) string {
 	return strings.TrimRightFunc(s, func(r rune) bool {

common/text/transform_test.go

@@ -57,7 +57,6 @@ line 3`
 	c := qt.New(t)
 
 	c.Assert(collected, qt.DeepEquals, []string{"line 1\n", "line 2\n", "\n", "line 3"})
-
 }
 
 func BenchmarkVisitLinesAfter(b *testing.B) {
@@ -68,9 +67,22 @@ func BenchmarkVisitLinesAfter(b *testing.B) {
 
 	for i := 0; i < b.N; i++ {
 		VisitLinesAfter(lines, func(s string) {
-
 		})
-
 	}
-
+}
+
+func BenchmarkTransliterate(b *testing.B) {
+	s := "ƀ Ɓ Ƃ ƃ Ƅ ƅ Ɔ Ƈ ƈ Ɖ Ɗ Ƌ ƌ ƍ Ǝ Ə Ɛ Ƒ ƒ Ɠ Ɣ ƕ Ɩ Ɨ Ƙ ƙ ƚ ƛ Ɯ Ɲ ƞ Ɵ Ơ ơ Ƣ ƣ Ƥ ƥ Ʀ Ƨ ƨ Ʃ ƪ ƫ Ƭ ƭ Ʈ Ư ư Ʊ Ʋ Ƴ ƴ Ƶ ƶ Ʒ Ƹ ƹ ƺ ƻ Ƽ ƽ ƾ ƿ ǀ ǁ ǂ ǃ DŽ Dž dž LJ Lj lj NJ Nj nj Ǎ ǎ Ǐ ǐ Ǒ ǒ Ǔ ǔ Ǖ ǖ Ǘ ǘ Ǚ ǚ Ǜ ǜ ǝ Ǟ ǟ Ǡ ǡ Ǣ ǣ Ǥ ǥ Ǧ ǧ Ǩ ǩ Ǫ ǫ Ǭ ǭ Ǯ ǯ ǰ DZ Dz dz Ǵ ǵ Ǻ ǻ Ǽ ǽ Ǿ ǿ Ȁ ȁ Ȃ ȃ"
+
+	b.Run("switch", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			_ = TransliterateString(s)
+		}
+	})
+
+	b.Run("map", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			_ = TransliterateStringMap(s)
+		}
+	})
 }

common/types/convert.go

@@ -80,7 +80,6 @@ func ToStringSlicePreserveStringE(v any) ([]string, error) {
 	default:
 		return nil, fmt.Errorf("failed to convert %T to a string slice", v)
 	}
-
 }
 
 // TypeToString converts v to a string if it's a valid string type.

common/types/convert_test.go

@@ -45,5 +45,4 @@ func TestToDuration(t *testing.T) {
 	c.Assert(ToDuration("200"), qt.Equals, 200*time.Millisecond)
 	c.Assert(ToDuration("4m"), qt.Equals, 4*time.Minute)
 	c.Assert(ToDuration("asdfadf"), qt.Equals, time.Duration(0))
-
 }

common/types/css/csstypes.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/types/evictingqueue.go

@@ -35,11 +35,11 @@ func NewEvictingStringQueue(size int) *EvictingStringQueue {
 }
 
 // Add adds a new string to the tail of the queue if it's not already there.
-func (q *EvictingStringQueue) Add(v string) {
+func (q *EvictingStringQueue) Add(v string) *EvictingStringQueue {
 	q.mu.Lock()
 	if q.set[v] {
 		q.mu.Unlock()
-		return
+		return q
 	}
 
 	if len(q.set) == q.size {
@@ -50,6 +50,17 @@ func (q *EvictingStringQueue) Add(v string) {
 	q.set[v] = true
 	q.vals = append(q.vals, v)
 	q.mu.Unlock()
+
+	return q
+}
+
+func (q *EvictingStringQueue) Len() int {
+	if q == nil {
+		return 0
+	}
+	q.mu.Lock()
+	defer q.mu.Unlock()
+	return len(q.vals)
 }
 
 // Contains returns whether the queue contains v.

common/types/hstring/stringtypes.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/types/hstring/stringtypes_test.go

@@ -1,4 +1,4 @@
-// Copyright 2022 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

common/types/types.go

@@ -92,5 +92,23 @@ type DevMarker interface {
 	DevOnly()
 }
 
+// Unwrapper is implemented by types that can unwrap themselves.
+type Unwrapper interface {
+	// Unwrapv is for internal use only.
+	// It got its slightly odd name to prevent collisions with user types.
+	Unwrapv() any
+}
+
+// LowHigh is typically used to represent a slice boundary.
+type LowHigh struct {
+	Low  int
+	High int
+}
+
 // This is only used for debugging purposes.
 var InvocationCounter atomic.Int64
+
+// NewTrue returns a pointer to b.
+func NewBool(b bool) *bool {
+	return &b
+}

common/urls/baseURL.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -23,10 +23,12 @@ import (
 // A BaseURL in Hugo is normally on the form scheme://path, but the
 // form scheme: is also valid (mailto:hugo@rules.com).
 type BaseURL struct {
-	url         *url.URL
-	WithPath    string
-	WithoutPath string
-	BasePath    string
+	url                     *url.URL
+	WithPath                string
+	WithPathNoTrailingSlash string
+	WithoutPath             string
+	BasePath                string
+	BasePathNoTrailingSlash string
 }
 
 func (b BaseURL) String() string {
@@ -92,19 +94,19 @@ func NewBaseURLFromString(b string) (BaseURL, error) {
 		return BaseURL{}, err
 	}
 	return newBaseURLFromURL(u)
-
 }
 
 func newBaseURLFromURL(u *url.URL) (BaseURL, error) {
-	baseURL := BaseURL{url: u, WithPath: u.String()}
-	var baseURLNoPath = baseURL.URL()
+	// A baseURL should always have a trailing slash, see #11669.
+	if !strings.HasSuffix(u.Path, "/") {
+		u.Path += "/"
+	}
+	baseURL := BaseURL{url: u, WithPath: u.String(), WithPathNoTrailingSlash: strings.TrimSuffix(u.String(), "/")}
+	baseURLNoPath := baseURL.URL()
 	baseURLNoPath.Path = ""
 	baseURL.WithoutPath = baseURLNoPath.String()
-
-	basePath := u.Path
-	if basePath != "" && basePath != "/" {
-		baseURL.BasePath = basePath
-	}
+	baseURL.BasePath = u.Path
+	baseURL.BasePathNoTrailingSlash = strings.TrimSuffix(u.Path, "/")
 
 	return baseURL, nil
 }

common/urls/baseURL_test.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -21,17 +21,24 @@ import (
 
 func TestBaseURL(t *testing.T) {
 	c := qt.New(t)
-	b, err := NewBaseURLFromString("http://example.com")
+
+	b, err := NewBaseURLFromString("http://example.com/")
 	c.Assert(err, qt.IsNil)
-	c.Assert(b.String(), qt.Equals, "http://example.com")
+	c.Assert(b.String(), qt.Equals, "http://example.com/")
+
+	b, err = NewBaseURLFromString("http://example.com")
+	c.Assert(err, qt.IsNil)
+	c.Assert(b.String(), qt.Equals, "http://example.com/")
+	c.Assert(b.WithPathNoTrailingSlash, qt.Equals, "http://example.com")
+	c.Assert(b.BasePath, qt.Equals, "/")
 
 	p, err := b.WithProtocol("webcal://")
 	c.Assert(err, qt.IsNil)
-	c.Assert(p.String(), qt.Equals, "webcal://example.com")
+	c.Assert(p.String(), qt.Equals, "webcal://example.com/")
 
 	p, err = b.WithProtocol("webcal")
 	c.Assert(err, qt.IsNil)
-	c.Assert(p.String(), qt.Equals, "webcal://example.com")
+	c.Assert(p.String(), qt.Equals, "webcal://example.com/")
 
 	_, err = b.WithProtocol("mailto:")
 	c.Assert(err, qt.Not(qt.IsNil))
@@ -57,11 +64,18 @@ func TestBaseURL(t *testing.T) {
 
 	b, err = NewBaseURLFromString("")
 	c.Assert(err, qt.IsNil)
-	c.Assert(b.String(), qt.Equals, "")
+	c.Assert(b.String(), qt.Equals, "/")
 
 	// BaseURL with sub path
 	b, err = NewBaseURLFromString("http://example.com/sub")
 	c.Assert(err, qt.IsNil)
-	c.Assert(b.String(), qt.Equals, "http://example.com/sub")
+	c.Assert(b.String(), qt.Equals, "http://example.com/sub/")
+	c.Assert(b.WithPathNoTrailingSlash, qt.Equals, "http://example.com/sub")
+	c.Assert(b.BasePath, qt.Equals, "/sub/")
+	c.Assert(b.BasePathNoTrailingSlash, qt.Equals, "/sub")
+
+	b, err = NewBaseURLFromString("http://example.com/sub/")
+	c.Assert(err, qt.IsNil)
+	c.Assert(b.String(), qt.Equals, "http://example.com/sub/")
 	c.Assert(b.HostURL(), qt.Equals, "http://example.com")
 }

compare/compare.go

@@ -52,3 +52,16 @@ func Eq(v1, v2 any) bool {
 
 	return v1 == v2
 }
+
+// ProbablyEq returns whether v1 is probably equal to v2.
+func ProbablyEq(v1, v2 any) bool {
+	if Eq(v1, v2) {
+		return true
+	}
+
+	if peqer, ok := v1.(ProbablyEqer); ok {
+		return peqer.ProbablyEq(v2)
+	}
+
+	return false
+}

compare/compare_strings_test.go

@@ -79,5 +79,4 @@ func BenchmarkStringSort(b *testing.B) {
 			})
 		}
 	})
-
 }

config/allconfig/allconfig.go

@@ -1,4 +1,4 @@
-// Copyright 2023 The Hugo Authors. All rights reserved.
+// Copyright 2024 The Hugo Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -27,8 +27,11 @@ import (
 	"time"
 
 	"github.com/gohugoio/hugo/cache/filecache"
+	"github.com/gohugoio/hugo/common/hugo"
 	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/common/maps"
+	"github.com/gohugoio/hugo/common/paths"
+	"github.com/gohugoio/hugo/common/types"
 	"github.com/gohugoio/hugo/common/urls"
 	"github.com/gohugoio/hugo/config"
 	"github.com/gohugoio/hugo/config/privacy"
@@ -62,6 +65,7 @@ type InternalConfig struct {
 	Verbose        bool
 	Clock          string
 	Watch          bool
+	FastRenderMode bool
 	LiveReloadPort int
 }
 
@@ -204,7 +208,7 @@ func (c Config) cloneForLang() *Config {
 	x.DisableKinds = copyStringSlice(x.DisableKinds)
 	x.DisableLanguages = copyStringSlice(x.DisableLanguages)
 	x.MainSections = copyStringSlice(x.MainSections)
-	x.IgnoreErrors = copyStringSlice(x.IgnoreErrors)
+	x.IgnoreLogs = copyStringSlice(x.IgnoreLogs)
 	x.IgnoreFiles = copyStringSlice(x.IgnoreFiles)
 	x.Theme = copyStringSlice(x.Theme)
 
@@ -282,12 +286,13 @@ func (c *Config) CompileConfig(logger loggers.Logger) error {
 
 	disabledLangs := make(map[string]bool)
 	for _, lang := range c.DisableLanguages {
-		if lang == c.DefaultContentLanguage {
-			return fmt.Errorf("cannot disable default content language %q", lang)
-		}
 		disabledLangs[lang] = true
 	}
 	for lang, language := range c.Languages {
+		if !language.Disabled && disabledLangs[lang] {
+			language.Disabled = true
+			c.Languages[lang] = language
+		}
 		if language.Disabled {
 			disabledLangs[lang] = true
 			if lang == c.DefaultContentLanguage {
@@ -296,9 +301,9 @@ func (c *Config) CompileConfig(logger loggers.Logger) error {
 		}
 	}
 
-	ignoredErrors := make(map[string]bool)
-	for _, err := range c.IgnoreErrors {
-		ignoredErrors[strings.ToLower(err)] = true
+	ignoredLogIDs := make(map[string]bool)
+	for _, err := range c.IgnoreLogs {
+		ignoredLogIDs[strings.ToLower(err)] = true
 	}
 
 	baseURL, err := urls.NewBaseURLFromString(c.BaseURL)
@@ -354,7 +359,7 @@ func (c *Config) CompileConfig(logger loggers.Logger) error {
 		BaseURLLiveReload: baseURL,
 		DisabledKinds:     disabledKinds,
 		DisabledLanguages: disabledLangs,
-		IgnoredErrors:     ignoredErrors,
+		IgnoredLogs:       ignoredLogIDs,
 		KindOutputFormats: kindOutputFormats,
 		CreateTitle:       helpers.GetTitleFunc(c.TitleCaseStyle),
 		IsUglyURLSection:  isUglyURL,
@@ -391,7 +396,7 @@ type ConfigCompiled struct {
 	KindOutputFormats map[string]output.Formats
 	DisabledKinds     map[string]bool
 	DisabledLanguages map[string]bool
-	IgnoredErrors     map[string]bool
+	IgnoredLogs       map[string]bool
 	CreateTitle       func(s string) string
 	IsUglyURLSection  func(section string) bool
 	IgnoreFile        func(filename string) bool
@@ -407,15 +412,19 @@ type ConfigCompiled struct {
 }
 
 // This may be set after the config is compiled.
-func (c *ConfigCompiled) SetMainSectionsIfNotSet(sections []string) {
+func (c *ConfigCompiled) SetMainSections(sections []string) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	if c.MainSections != nil {
-		return
-	}
 	c.MainSections = sections
 }
 
+// IsMainSectionsSet returns whether the main sections have been set.
+func (c *ConfigCompiled) IsMainSectionsSet() bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.MainSections != nil
+}
+
 // This is set after the config is compiled by the server command.
 func (c *ConfigCompiled) SetBaseURL(baseURL, baseURLLiveReload urls.BaseURL) {
 	c.BaseURL = baseURL
@@ -424,7 +433,6 @@ func (c *ConfigCompiled) SetBaseURL(baseURL, baseURLLiveReload urls.BaseURL) {
 
 // RootConfig holds all the top-level configuration options in Hugo
 type RootConfig struct {
-
 	// The base URL of the site.
 	// Note that the default value is empty, but Hugo requires a valid URL (e.g. "https://example.com/") to work properly.
 	// <docsmeta>{"identifiers": ["URL"] }</docsmeta>
@@ -495,8 +503,8 @@ type RootConfig struct {
 	// Enable to disable the build lock file.
 	NoBuildLock bool
 
-	// A list of error IDs to ignore.
-	IgnoreErrors []string
+	// A list of log IDs to ignore.
+	IgnoreLogs []string
 
 	// A list of regexps that match paths to ignore.
 	// Deprecated: Use the settings on module imports.
@@ -647,13 +655,16 @@ type Configs struct {
 	LanguageConfigMap   map[string]*Config
 	LanguageConfigSlice []*Config
 
-	IsMultihost           bool
-	Languages             langs.Languages
-	LanguagesDefaultFirst langs.Languages
+	IsMultihost bool
 
 	Modules       modules.Modules
 	ModulesClient *modules.Client
 
+	// All below is set in Init.
+	Languages             langs.Languages
+	LanguagesDefaultFirst langs.Languages
+	ContentPathParser     paths.PathParser
+
 	configLangs []config.AllProvider
 }
 
@@ -673,6 +684,59 @@ func (c *Configs) IsZero() bool {
 }
 
 func (c *Configs) Init() error {
+	var languages langs.Languages
+	defaultContentLanguage := c.Base.DefaultContentLanguage
+	for k, v := range c.LanguageConfigMap {
+		c.LanguageConfigSlice = append(c.LanguageConfigSlice, v)
+		languageConf := v.Languages[k]
+		language, err := langs.NewLanguage(k, defaultContentLanguage, v.TimeZone, languageConf)
+		if err != nil {
+			return err
+		}
+		languages = append(languages, language)
+	}
+
+	// Sort the sites by language weight (if set) or lang.
+	sort.Slice(languages, func(i, j int) bool {
+		li := languages[i]
+		lj := languages[j]
+		if li.Weight != lj.Weight {
+			return li.Weight < lj.Weight
+		}
+		return li.Lang < lj.Lang
+	})
+
+	for _, l := range languages {
+		c.LanguageConfigSlice = append(c.LanguageConfigSlice, c.LanguageConfigMap[l.Lang])
+	}
+
+	// Filter out disabled languages.
+	var n int
+	for _, l := range languages {
+		if !l.Disabled {
+			languages[n] = l
+			n++
+		}
+	}
+	languages = languages[:n]
+
+	var languagesDefaultFirst langs.Languages
+	for _, l := range languages {
+		if l.Lang == defaultContentLanguage {
+			languagesDefaultFirst = append(languagesDefaultFirst, l)
+		}
+	}
+	for _, l := range languages {
+		if l.Lang != defaultContentLanguage {
+			languagesDefaultFirst = append(languagesDefaultFirst, l)
+		}
+	}
+
+	c.Languages = languages
+	c.LanguagesDefaultFirst = languagesDefaultFirst
+
+	c.ContentPathParser = paths.PathParser{LanguageIndex: languagesDefaultFirst.AsIndexSet(), IsLangDisabled: c.Base.IsLangDisabled}
+
 	c.configLangs = make([]config.AllProvider, len(c.Languages))
 	for i, l := range c.LanguagesDefaultFirst {
 		c.configLangs[i] = ConfigLanguage{
@@ -750,7 +814,6 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 	}
 
 	langConfigMap := make(map[string]*Config)
-	var langConfigs []*Config
 
 	languagesConfig := cfg.GetStringMap("languages")
 	var isMultiHost bool
@@ -784,7 +847,7 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 					// We accidentally allowed it in the past, so we need to support it a little longer,
 					// But log a warning.
 					if _, found := params[kk]; !found {
-						helpers.Deprecated(fmt.Sprintf("config: languages.%s.%s: custom params on the language top level", k, kk), fmt.Sprintf("Put the value below [languages.%s.params]. See https://gohugo.io/content-management/multilingual/#changes-in-hugo-01120", k), false)
+						hugo.Deprecate(fmt.Sprintf("config: languages.%s.%s: custom params on the language top level", k, kk), fmt.Sprintf("Put the value below [languages.%s.params]. See https://gohugo.io/content-management/multilingual/#changes-in-hugo-01120", k), "v0.112.0")
 						params[kk] = vv
 					}
 				}
@@ -839,6 +902,18 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 				return nil, err
 			}
 
+			// Adjust Goldmark config defaults for multilingual, single-host sites.
+			if len(languagesConfig) > 1 && !isMultiHost && !clone.Markup.Goldmark.DuplicateResourceFiles {
+				if !clone.Markup.Goldmark.DuplicateResourceFiles {
+					if clone.Markup.Goldmark.RenderHooks.Link.EnableDefault == nil {
+						clone.Markup.Goldmark.RenderHooks.Link.EnableDefault = types.NewBool(true)
+					}
+					if clone.Markup.Goldmark.RenderHooks.Image.EnableDefault == nil {
+						clone.Markup.Goldmark.RenderHooks.Image.EnableDefault = types.NewBool(true)
+					}
+				}
+			}
+
 			langConfigMap[k] = clone
 		case maps.ParamsMergeStrategy:
 		default:
@@ -847,65 +922,24 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 		}
 	}
 
-	var languages langs.Languages
-	defaultContentLanguage := all.DefaultContentLanguage
-	for k, v := range langConfigMap {
-		languageConf := v.Languages[k]
-		language, err := langs.NewLanguage(k, defaultContentLanguage, v.TimeZone, languageConf)
-		if err != nil {
-			return nil, err
-		}
-		languages = append(languages, language)
-	}
-
-	// Sort the sites by language weight (if set) or lang.
-	sort.Slice(languages, func(i, j int) bool {
-		li := languages[i]
-		lj := languages[j]
-		if li.Weight != lj.Weight {
-			return li.Weight < lj.Weight
-		}
-		return li.Lang < lj.Lang
-	})
-
-	for _, l := range languages {
-		langConfigs = append(langConfigs, langConfigMap[l.Lang])
-	}
-
-	var languagesDefaultFirst langs.Languages
-	for _, l := range languages {
-		if l.Lang == defaultContentLanguage {
-			languagesDefaultFirst = append(languagesDefaultFirst, l)
-		}
-	}
-	for _, l := range languages {
-		if l.Lang != defaultContentLanguage {
-			languagesDefaultFirst = append(languagesDefaultFirst, l)
-		}
-	}
-
 	bcfg.PublishDir = all.PublishDir
 	res.BaseConfig = bcfg
 	all.CommonDirs.CacheDir = bcfg.CacheDir
-	for _, l := range langConfigs {
+	for _, l := range langConfigMap {
 		l.CommonDirs.CacheDir = bcfg.CacheDir
 	}
 
 	cm := &Configs{
-		Base:                  all,
-		LanguageConfigMap:     langConfigMap,
-		LanguageConfigSlice:   langConfigs,
-		LoadingInfo:           res,
-		IsMultihost:           isMultiHost,
-		Languages:             languages,
-		LanguagesDefaultFirst: languagesDefaultFirst,
+		Base:              all,
+		LanguageConfigMap: langConfigMap,
+		LoadingInfo:       res,
+		IsMultihost:       isMultiHost,
 	}
 
 	return cm, nil
 }
 
 func decodeConfigFromParams(fs afero.Fs, logger loggers.Logger, bcfg config.BaseConfig, p config.Provider, target *Config, keys []string) error {
-
 	var decoderSetups []decodeWeight
 
 	if len(keys) == 0 {
@@ -932,7 +966,7 @@ func decodeConfigFromParams(fs afero.Fs, logger loggers.Logger, bcfg config.Base
 	})
 
 	for _, v := range decoderSetups {
-		p := decodeConfig{p: p, c: target, fs: fs, bcfg: bcfg}
+		p := decodeConfig{p: p, c: target, fs: fs, logger: logger, bcfg: bcfg}
 		if err := v.decode(v, p); err != nil {
 			return fmt.Errorf("failed to decode %q: %w", v.key, err)
 		}

config/allconfig/allconfig_integration_test.go

@@ -10,7 +10,6 @@ import (
 )
 
 func TestDirsMount(t *testing.T) {
-
 	files := `
 -- hugo.toml --
 baseURL = "https://example.com"
@@ -44,7 +43,7 @@ Title: {{ .Title }}
 		hugolib.IntegrationTestConfig{T: t, TxtarString: files},
 	).Build()
 
-	//b.AssertFileContent("public/p1/index.html", "Title: p1")
+	// b.AssertFileContent("public/p1/index.html", "Title: p1")
 
 	sites := b.H.Sites
 	b.Assert(len(sites), qt.Equals, 2)
@@ -58,7 +57,7 @@ Title: {{ .Title }}
 	enConcp := sites[0].Conf
 	enConf := enConcp.GetConfig().(*allconfig.Config)
 
-	b.Assert(enConcp.BaseURL().String(), qt.Equals, "https://example.com")
+	b.Assert(enConcp.BaseURL().String(), qt.Equals, "https://example.com/")
 	modConf := enConf.Module
 	b.Assert(modConf.Mounts, qt.HasLen, 8)
 	b.Assert(modConf.Mounts[0].Source, qt.Equals, filepath.FromSlash("content/en"))
@@ -67,11 +66,9 @@ Title: {{ .Title }}
 	b.Assert(modConf.Mounts[1].Source, qt.Equals, filepath.FromSlash("content/sv"))
 	b.Assert(modConf.Mounts[1].Target, qt.Equals, "content")
 	b.Assert(modConf.Mounts[1].Lang, qt.Equals, "sv")
-
 }
 
 func TestConfigAliases(t *testing.T) {
-
 	files := `
 -- hugo.toml --
 baseURL = "https://example.com"