tpl/data: Clean up data namespace

- Move the main GetCSV and GetJSON into data.go.
- Add error returns to GetCSV and GetJSON.
- Add http client to Namespace for test mocking.
- Send accept headers on remote requests. Fixes #3395
- Return an error on non-2XX HTTP response codes and don't retry.
- Move cache tests to cache_test.go.

tpl/data/cache_test.go

@@ -0,0 +1,63 @@
+// Copyright 2017 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 data
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/spf13/afero"
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCache(t *testing.T) {
+	t.Parallel()
+
+	fs := new(afero.MemMapFs)
+
+	for i, test := range []struct {
+		path    string
+		content []byte
+		ignore  bool
+	}{
+		{"http://Foo.Bar/foo_Bar-Foo", []byte(`T€st Content 123`), false},
+		{"fOO,bar:foo%bAR", []byte(`T€st Content 123 fOO,bar:foo%bAR`), false},
+		{"FOo/BaR.html", []byte(`FOo/BaR.html T€st Content 123`), false},
+		{"трям/трям", []byte(`T€st трям/трям Content 123`), false},
+		{"은행", []byte(`T€st C은행ontent 123`), false},
+		{"Банковский кассир", []byte(`Банковский кассир T€st Content 123`), false},
+		{"Банковский кассир", []byte(`Банковский кассир T€st Content 456`), true},
+	} {
+		msg := fmt.Sprintf("Test #%d: %v", i, test)
+
+		cfg := viper.New()
+
+		c, err := getCache(test.path, fs, cfg, test.ignore)
+		assert.NoError(t, err, msg)
+		assert.Nil(t, c, msg)
+
+		err = writeCache(test.path, test.content, fs, cfg, test.ignore)
+		assert.NoError(t, err, msg)
+
+		c, err = getCache(test.path, fs, cfg, test.ignore)
+		assert.NoError(t, err, msg)
+
+		if test.ignore {
+			assert.Nil(t, c, msg)
+		} else {
+			assert.Equal(t, string(test.content), string(c))
+		}
+	}
+}