Make label templates have consistent behavior and priority (#23749) (#24071)

Backport #23749

Fix https://github.com/go-gitea/gitea/issues/23715

Backported manually and tested manually.

modules/repository/init.go

@@ -8,7 +8,6 @@ import (
 	"context"
 	"fmt"
 	"os"
-	"path"
 	"path/filepath"
 	"sort"
 	"strings"
@@ -27,6 +26,11 @@ import (
 	asymkey_service "code.gitea.io/gitea/services/asymkey"
 )
 
+type OptionFile struct {
+	DisplayName string
+	Description string
+}
+
 var (
 	// Gitignores contains the gitiginore files
 	Gitignores []string
@@ -37,65 +41,73 @@ var (
 	// Readmes contains the readme files
 	Readmes []string
 
-	// LabelTemplates contains the label template files and the list of labels for each file
-	LabelTemplates map[string]string
+	// LabelTemplateFiles contains the label template files, each item has its DisplayName and Description
+	LabelTemplateFiles   []OptionFile
+	labelTemplateFileMap = map[string]string{} // DisplayName => FileName mapping
 )
 
-// LoadRepoConfig loads the repository config
-func LoadRepoConfig() {
-	// Load .gitignore and license files and readme templates.
-	types := []string{"gitignore", "license", "readme", "label"}
-	typeFiles := make([][]string, 4)
-	for i, t := range types {
-		files, err := options.Dir(t)
-		if err != nil {
-			log.Fatal("Failed to get %s files: %v", t, err)
-		}
-		if t == "label" {
-			for i, f := range files {
-				ext := strings.ToLower(filepath.Ext(f))
-				if ext == ".yaml" || ext == ".yml" {
-					files[i] = f[:len(f)-len(ext)]
-				}
-			}
-		}
-		customPath := path.Join(setting.CustomPath, "options", t)
-		isDir, err := util.IsDir(customPath)
-		if err != nil {
-			log.Fatal("Failed to get custom %s files: %v", t, err)
-		}
-		if isDir {
-			customFiles, err := util.StatDir(customPath)
-			if err != nil {
-				log.Fatal("Failed to get custom %s files: %v", t, err)
-			}
+type optionFileList struct {
+	all    []string // all files provided by bindata & custom-path. Sorted.
+	custom []string // custom files provided by custom-path. Non-sorted, internal use only.
+}
 
-			for _, f := range customFiles {
-				if !util.SliceContainsString(files, f, true) {
-					files = append(files, f)
-				}
+// mergeCustomLabelFiles merges the custom label files. Always use the file's main name (DisplayName) as the key to de-duplicate.
+func mergeCustomLabelFiles(fl optionFileList) []string {
+	exts := map[string]int{"": 0, ".yml": 1, ".yaml": 2} // "yaml" file has the highest priority to be used.
+
+	m := map[string]string{}
+	merge := func(list []string) {
+		sort.Slice(list, func(i, j int) bool { return exts[filepath.Ext(list[i])] < exts[filepath.Ext(list[j])] })
+		for _, f := range list {
+			m[strings.TrimSuffix(f, filepath.Ext(f))] = f
+		}
+	}
+	merge(fl.all)
+	merge(fl.custom)
+
+	files := make([]string, 0, len(m))
+	for _, f := range m {
+		files = append(files, f)
+	}
+	sort.Strings(files)
+	return files
+}
+
+// LoadRepoConfig loads the repository config
+func LoadRepoConfig() error {
+	types := []string{"gitignore", "license", "readme", "label"} // option file directories
+	typeFiles := make([]optionFileList, len(types))
+	for i, t := range types {
+		var err error
+		if typeFiles[i].all, err = options.Dir(t); err != nil {
+			return fmt.Errorf("failed to list %s files: %w", t, err)
+		}
+		sort.Strings(typeFiles[i].all)
+		customPath := filepath.Join(setting.CustomPath, "options", t)
+		if isDir, err := util.IsDir(customPath); err != nil {
+			return fmt.Errorf("failed to check custom %s dir: %w", t, err)
+		} else if isDir {
+			if typeFiles[i].custom, err = util.StatDir(customPath); err != nil {
+				return fmt.Errorf("failed to list custom %s files: %w", t, err)
 			}
 		}
-		typeFiles[i] = files
 	}
 
-	Gitignores = typeFiles[0]
-	Licenses = typeFiles[1]
-	Readmes = typeFiles[2]
-	LabelTemplatesFiles := typeFiles[3]
-	sort.Strings(Gitignores)
-	sort.Strings(Licenses)
-	sort.Strings(Readmes)
-	sort.Strings(LabelTemplatesFiles)
+	Gitignores = typeFiles[0].all
+	Licenses = typeFiles[1].all
+	Readmes = typeFiles[2].all
 
 	// Load label templates
-	LabelTemplates = make(map[string]string)
-	for _, templateFile := range LabelTemplatesFiles {
-		labels, err := label.LoadFormatted(templateFile)
+	LabelTemplateFiles = nil
+	labelTemplateFileMap = map[string]string{}
+	for _, file := range mergeCustomLabelFiles(typeFiles[3]) {
+		description, err := label.LoadTemplateDescription(file)
 		if err != nil {
-			log.Error("Failed to load labels: %v", err)
+			return fmt.Errorf("failed to load labels: %w", err)
 		}
-		LabelTemplates[templateFile] = labels
+		displayName := strings.TrimSuffix(file, filepath.Ext(file))
+		labelTemplateFileMap[displayName] = file
+		LabelTemplateFiles = append(LabelTemplateFiles, OptionFile{DisplayName: displayName, Description: description})
 	}
 
 	// Filter out invalid names and promote preferred licenses.
@@ -111,6 +123,7 @@ func LoadRepoConfig() {
 		}
 	}
 	Licenses = sortedLicenses
+	return nil
 }
 
 func prepareRepoCommit(ctx context.Context, repo *repo_model.Repository, tmpDir, repoPath string, opts CreateRepoOptions) error {
@@ -344,7 +357,7 @@ func initRepository(ctx context.Context, repoPath string, u *user_model.User, re
 
 // InitializeLabels adds a label set to a repository using a template
 func InitializeLabels(ctx context.Context, id int64, labelTemplate string, isOrg bool) error {
-	list, err := label.GetTemplateFile(labelTemplate)
+	list, err := LoadTemplateLabelsByDisplayName(labelTemplate)
 	if err != nil {
 		return err
 	}
@@ -370,3 +383,11 @@ func InitializeLabels(ctx context.Context, id int64, labelTemplate string, isOrg
 	}
 	return nil
 }
+
+// LoadTemplateLabelsByDisplayName loads a label template by its display name
+func LoadTemplateLabelsByDisplayName(displayName string) ([]*label.Label, error) {
+	if fileName, ok := labelTemplateFileMap[displayName]; ok {
+		return label.LoadTemplateFile(fileName)
+	}
+	return nil, label.ErrTemplateLoad{TemplateFile: displayName, OriginalError: fmt.Errorf("label template %q not found", displayName)}
+}