tpl/transform: Add transform.Unmarshal func

Fixes #5428

cache/namedmemcache/named_cache_test.go

@@ -0,0 +1,80 @@
+// 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"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestNamedCache(t *testing.T) {
+	t.Parallel()
+	assert := require.New(t)
+
+	cache := New()
+
+	counter := 0
+	create := func() (interface{}, error) {
+		counter++
+		return counter, nil
+	}
+
+	for i := 0; i < 5; i++ {
+		v1, err := cache.GetOrCreate("a1", create)
+		assert.NoError(err)
+		assert.Equal(1, v1)
+		v2, err := cache.GetOrCreate("a2", create)
+		assert.NoError(err)
+		assert.Equal(2, v2)
+	}
+
+	cache.Clear()
+
+	v3, err := cache.GetOrCreate("a2", create)
+	assert.NoError(err)
+	assert.Equal(3, v3)
+}
+
+func TestNamedCacheConcurrent(t *testing.T) {
+	t.Parallel()
+
+	assert := require.New(t)
+
+	var wg sync.WaitGroup
+
+	cache := New()
+
+	create := func(i int) func() (interface{}, error) {
+		return func() (interface{}, 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))
+				assert.NoError(err)
+				assert.Equal(j, v)
+			}
+		}()
+	}
+	wg.Wait()
+}