github.com/shohhei1126/hugo@v0.42.2-0.20180623210752-3d5928889ad7/hugolib/pages_language_merge.go (about) 1 // Copyright 2018 The Hugo Authors. All rights reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // http://www.apache.org/licenses/LICENSE-2.0 7 // 8 // Unless required by applicable law or agreed to in writing, software 9 // distributed under the License is distributed on an "AS IS" BASIS, 10 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 11 // See the License for the specific language governing permissions and 12 // limitations under the License. 13 14 package hugolib 15 16 import ( 17 "fmt" 18 ) 19 20 var ( 21 _ pagesLanguageMerger = (*Pages)(nil) 22 ) 23 24 type pagesLanguageMerger interface { 25 MergeByLanguage(other Pages) Pages 26 // Needed for integration with the tpl package. 27 MergeByLanguageInterface(other interface{}) (interface{}, error) 28 } 29 30 // MergeByLanguage supplies missing translations in p1 with values from p2. 31 // The result is sorted by the default sort order for pages. 32 func (p1 Pages) MergeByLanguage(p2 Pages) Pages { 33 merge := func(pages *Pages) { 34 m := make(map[string]bool) 35 for _, p := range *pages { 36 m[p.TranslationKey()] = true 37 } 38 39 for _, p := range p2 { 40 if _, found := m[p.TranslationKey()]; !found { 41 *pages = append(*pages, p) 42 } 43 } 44 45 pages.Sort() 46 } 47 48 out, _ := spc.getP("pages.MergeByLanguage", merge, p1, p2) 49 50 return out 51 } 52 53 // MergeByLanguageInterface is the generic version of MergeByLanguage. It 54 // is here just so it can be called from the tpl package. 55 func (p1 Pages) MergeByLanguageInterface(in interface{}) (interface{}, error) { 56 p2, ok := in.(Pages) 57 if !ok { 58 return nil, fmt.Errorf("%T cannot be merged by language", in) 59 } 60 return p1.MergeByLanguage(p2), nil 61 }