ref: c624a77992c4f7c1bcb5f659e89332d8588986b7
parent: 020086cb2b0396909d831abf66b8f1455e6f7e6a
author: Bjørn Erik Pedersen <bjorn.erik.pedersen@gmail.com>
date: Thu Jul 11 03:12:44 EDT 2019
tpl/collections: Add Merge function Merges two maps recursively and returns a new one. Merge is case-insensitive. Fixes #5992
--- a/tpl/collections/init.go
+++ b/tpl/collections/init.go
@@ -183,6 +183,16 @@
},
)
+ ns.AddMethodMapping(ctx.Merge,
+ []string{"merge"},+ [][2]string{+ {`{{ dict "title" "Hugo Rocks!" | collections.Merge (dict "title" "Default Title" "description" "Yes, Hugo Rocks!") | sort }}`,+ `[Yes, Hugo Rocks! Hugo Rocks!]`},
+ {`{{ merge (dict "title" "Default Title" "description" "Yes, Hugo Rocks!") (dict "title" "Hugo Rocks!") | sort }}`,+ `[Yes, Hugo Rocks! Hugo Rocks!]`},
+ },
+ )
+
return ns
}
--- /dev/null
+++ b/tpl/collections/merge.go
@@ -1,0 +1,98 @@
+// Copyright 2019 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 (
+ "reflect"
+ "strings"
+
+ "github.com/gohugoio/hugo/common/hreflect"
+
+ "github.com/pkg/errors"
+)
+
+// Merge creates a copy of dst and merges src into it.
+// Currently only maps supported. Key handling is case insensitive.
+func (ns *Namespace) Merge(src, dst interface{}) (interface{}, error) {+
+ vdst, vsrc := reflect.ValueOf(dst), reflect.ValueOf(src)
+
+ if vdst.Kind() != reflect.Map {+ return nil, errors.Errorf("destination must be a map, got %T", dst)+ }
+
+ if !hreflect.IsTruthfulValue(vsrc) {+ return dst, nil
+ }
+
+ if vsrc.Kind() != reflect.Map {+ return nil, errors.Errorf("source must be a map, got %T", src)+ }
+
+ if vsrc.Type() != vdst.Type() {+ return nil, errors.Errorf("incompatible map types, got %T to %T", src, dst)+ }
+
+ return mergeMap(vdst, vsrc).Interface(), nil
+}
+
+func caseInsensitiveLookup(m, k reflect.Value) (reflect.Value, bool) {+ if m.Type().Key().Kind() != reflect.String || k.Kind() != reflect.String {+ // Fall back to direct lookup.
+ v := m.MapIndex(k)
+ return v, hreflect.IsTruthfulValue(v)
+ }
+
+ for _, key := range m.MapKeys() {+ if strings.EqualFold(k.String(), key.String()) {+ return m.MapIndex(key), true
+ }
+
+ }
+
+ return reflect.Value{}, false+}
+
+func mergeMap(dst, src reflect.Value) reflect.Value {+
+ out := reflect.MakeMap(dst.Type())
+
+ // Copy the destination map.
+ for _, key := range dst.MapKeys() {+ v := dst.MapIndex(key)
+ out.SetMapIndex(key, v)
+ }
+
+ // Add all keys in src not already in destination.
+ // Maps of the same type will be merged.
+ for _, key := range src.MapKeys() {+ sv := src.MapIndex(key)
+ dv, found := caseInsensitiveLookup(dst, key)
+
+ if found {+ // If both are the same map type, merge.
+ dve := dv.Elem()
+ if dve.Kind() == reflect.Map {+ sve := sv.Elem()
+ if dve.Type() == sve.Type() {+ out.SetMapIndex(key, mergeMap(dve, sve))
+ }
+ }
+ } else {+ out.SetMapIndex(key, sv)
+ }
+ }
+
+ return out
+}
--- /dev/null
+++ b/tpl/collections/merge_test.go
@@ -1,0 +1,173 @@
+// Copyright 2019 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 (
+ "bytes"
+ "fmt"
+ "reflect"
+ "runtime"
+ "strings"
+ "testing"
+
+ "github.com/gohugoio/hugo/parser"
+
+ "github.com/gohugoio/hugo/parser/metadecoders"
+
+ "github.com/gohugoio/hugo/deps"
+ "github.com/stretchr/testify/require"
+)
+
+func TestMerge(t *testing.T) {+
+ ns := New(&deps.Deps{})+
+ simpleMap := map[string]interface{}{"a": 1, "b": 2}+
+ for i, test := range []struct {+ name string
+ dst interface{}+ src interface{}+ expect interface{}+ isErr bool
+ }{+ {+ "basic",
+ map[string]interface{}{"a": 1, "b": 2},+ map[string]interface{}{"a": 42, "c": 3},+ map[string]interface{}{"a": 1, "b": 2, "c": 3}, false},+ {+ "basic case insensitive",
+ map[string]interface{}{"a": 1, "b": 2},+ map[string]interface{}{"A": 42, "c": 3},+ map[string]interface{}{"a": 1, "b": 2, "c": 3}, false},+ {+ "nested",
+ map[string]interface{}{"a": 1, "b": map[string]interface{}{"d": 1, "e": 2}},+ map[string]interface{}{"a": 42, "c": 3, "b": map[string]interface{}{"d": 55, "e": 66, "f": 3}},+ map[string]interface{}{"a": 1, "b": map[string]interface{}{"d": 1, "e": 2, "f": 3}, "c": 3}, false},+ {"src nil", simpleMap, nil, simpleMap, false},+ // Error cases.
+ {"dst not a map", "not a map", nil, nil, true},+ {"src not a map", simpleMap, "not a map", nil, true},+ {"diferent map typs", simpleMap, map[int]interface{}{32: "a"}, nil, true},+ {"all nil", nil, nil, nil, true},+ } {+
+ test := test
+
+ t.Run(test.name, func(t *testing.T) {+ t.Parallel()
+ errMsg := fmt.Sprintf("[%d] %v", i, test)+
+ assert := require.New(t)
+
+ srcStr, dstStr := fmt.Sprint(test.src), fmt.Sprint(test.dst)
+
+ result, err := ns.Merge(test.src, test.dst)
+
+ if test.isErr {+ assert.Error(err, errMsg)
+ return
+ }
+
+ assert.NoError(err, errMsg)
+ assert.Equal(test.expect, result, errMsg)
+
+ // map sort in fmt was fixed in go 1.12.
+ if !strings.HasPrefix(runtime.Version(), "go1.11") {+ // Verify that the original maps are preserved.
+ assert.Equal(srcStr, fmt.Sprint(test.src))
+ assert.Equal(dstStr, fmt.Sprint(test.dst))
+ }
+
+ })
+ }
+}
+
+func TestMergeDataFormats(t *testing.T) {+ assert := require.New(t)
+ ns := New(&deps.Deps{})+
+ toml1 := `
+V1 = "v1_1"
+
+[V2s]
+V21 = "v21_1"
+
+`
+
+ toml2 := `
+V1 = "v1_2"
+V2 = "v2_2"
+
+[V2s]
+V21 = "v21_2"
+V22 = "v22_2"
+
+`
+
+ meta1, err := metadecoders.Default.UnmarshalToMap([]byte(toml1), metadecoders.TOML)
+ assert.NoError(err)
+ meta2, err := metadecoders.Default.UnmarshalToMap([]byte(toml2), metadecoders.TOML)
+ assert.NoError(err)
+
+ for _, format := range []metadecoders.Format{metadecoders.JSON, metadecoders.YAML, metadecoders.TOML} {+
+ var dataStr1, dataStr2 bytes.Buffer
+ err = parser.InterfaceToConfig(meta1, format, &dataStr1)
+ assert.NoError(err)
+ err = parser.InterfaceToConfig(meta2, format, &dataStr2)
+ assert.NoError(err)
+
+ dst, err := metadecoders.Default.UnmarshalToMap(dataStr1.Bytes(), format)
+ assert.NoError(err)
+ src, err := metadecoders.Default.UnmarshalToMap(dataStr2.Bytes(), format)
+ assert.NoError(err)
+
+ merged, err := ns.Merge(src, dst)
+ assert.NoError(err)
+
+ assert.Equal(map[string]interface{}{"V1": "v1_1", "V2": "v2_2", "V2s": map[string]interface{}{"V21": "v21_1", "V22": "v22_2"}}, merged)+ }
+
+}
+
+func TestCaseInsensitiveMapLookup(t *testing.T) {+ assert := require.New(t)
+
+ m1 := reflect.ValueOf(map[string]interface{}{+ "a": 1,
+ "B": 2,
+ })
+
+ m2 := reflect.ValueOf(map[int]interface{}{+ 1: 1,
+ 2: 2,
+ })
+
+ var found bool
+
+ a, found := caseInsensitiveLookup(m1, reflect.ValueOf("A"))+ assert.True(found)
+ assert.Equal(1, a.Interface())
+
+ b, found := caseInsensitiveLookup(m1, reflect.ValueOf("b"))+ assert.True(found)
+ assert.Equal(2, b.Interface())
+
+ two, found := caseInsensitiveLookup(m2, reflect.ValueOf(2))
+ assert.True(found)
+ assert.Equal(2, two.Interface())
+}