fix: panic if theme defines custom copied dirs & files other than bundle

This fixes #110 .

main.go

@@ -43,6 +43,7 @@ toc: {{.Toc}}
 )
 
 var globalConfig *GlobalConfig
+var themeConfig *ThemeConfig
 var rootPath string
 
 func main() {
@@ -187,8 +188,8 @@ func ParseGlobalConfigByCli(c *cli.Context, develop bool) {
 
 func ParseGlobalConfigWrap(root string, develop bool) {
 	rootPath = root
-	globalConfig = ParseGlobalConfig(filepath.Join(rootPath, "config.yml"), develop)
-	if globalConfig == nil {
+	globalConfig, themeConfig = ParseGlobalConfig(filepath.Join(rootPath, "config.yml"), develop)
+	if globalConfig == nil || themeConfig == nil {
 		return
 	}
 }

parse.go

@@ -148,12 +148,12 @@ func ReplaceRootFlag(content string) string {
 	return strings.Replace(content, "-/", globalConfig.Site.Root+"/", -1)
 }
 
-func ParseGlobalConfig(configPath string, develop bool) *GlobalConfig {
+func ParseGlobalConfig(configPath string, develop bool) (*GlobalConfig, *ThemeConfig) {
 	var config *GlobalConfig
 	// Parse Global Config
 	data, err := os.ReadFile(configPath)
 	if err != nil {
-		return nil
+		return nil, nil
 	}
 	if err = yaml.Unmarshal(data, &config); err != nil {
 		Fatal(err.Error())
@@ -181,7 +181,7 @@ func ParseGlobalConfig(configPath string, develop bool) *GlobalConfig {
 	for item, langItem := range themeConfig.Lang {
 		config.I18n[item] = langItem[config.Site.Lang]
 	}
-	return config
+	return config, themeConfig
 }
 
 func ParseThemeConfig(configPath string) *ThemeConfig {

serve.go

@@ -3,6 +3,7 @@ package main
 import (
 	"os"
 	"path/filepath"
+	"reflect"
 
 	"github.com/InkProject/ink.go"
 	"github.com/facebookgo/symwalk"
@@ -13,12 +14,61 @@ import (
 var watcher *fsnotify.Watcher
 var conn *websocket.Conn
 
+func buildWatchList() (files []string, dirs []string) {
+	dirs = []string{
+		filepath.Join(rootPath, "source"),
+	}
+	files = []string{
+		filepath.Join(rootPath, "config.yml"),
+		filepath.Join(themePath),
+	}
+
+	// Add files and directories defined in theme's config.yml to watcher
+	for _, themeCopiedPath := range themeConfig.Copy {
+		if themeCopiedPath != "" {
+			fullPath := filepath.Join(themePath, themeCopiedPath)
+			s, err := os.Stat(fullPath)
+			if s == nil || err != nil {
+				continue
+			}
+
+			if s.IsDir() {
+				dirs = append(dirs, fullPath)
+			} else {
+				files = append(files, fullPath)
+			}
+		}
+	}
+	return files, dirs
+}
+
+// Add files and dirs to watcher
+func configureWatcher(watcher *fsnotify.Watcher, files []string, dirs []string) error {
+	for _, source := range dirs {
+		symwalk.Walk(source, func(path string, f os.FileInfo, err error) error {
+			if f != nil && f.IsDir() {
+				if err := watcher.Add(path); err != nil {
+					Warn(err.Error())
+				}
+			}
+			return nil
+		})
+	}
+	for _, source := range files {
+		if err := watcher.Add(source); err != nil {
+			Warn(err.Error())
+		}
+	}
+	return nil
+}
+
 func Watch() {
 	// Listen watched file change event
 	if watcher != nil {
 		watcher.Close()
 	}
 	watcher, _ = fsnotify.NewWatcher()
+	files, dirs := buildWatchList()
 	go func() {
 		for {
 			select {
@@ -27,6 +77,15 @@ func Watch() {
 					// Handle when file change
 					Log(event.Name)
 					ParseGlobalConfigWrap(rootPath, true)
+
+					newFiles, newDirs := buildWatchList()
+					// If file list changed, reconfigure watcher
+					if !reflect.DeepEqual(files, newFiles) || !reflect.DeepEqual(dirs, newDirs) {
+						configureWatcher(watcher, newFiles, newDirs)
+						files = newFiles
+						dirs = newDirs
+					}
+
 					Build()
 					if conn != nil {
 						if err := conn.WriteMessage(websocket.TextMessage, []byte("change")); err != nil {
@@ -39,29 +98,7 @@ func Watch() {
 			}
 		}
 	}()
-	var dirs = []string{
-		filepath.Join(rootPath, "source"),
-		filepath.Join(themePath, "bundle"),
-	}
-	var files = []string{
-		filepath.Join(rootPath, "config.yml"),
-		filepath.Join(themePath),
-	}
-	for _, source := range dirs {
-		symwalk.Walk(source, func(path string, f os.FileInfo, err error) error {
-			if f.IsDir() {
-				if err := watcher.Add(path); err != nil {
-					Warn(err.Error())
-				}
-			}
-			return nil
-		})
-	}
-	for _, source := range files {
-		if err := watcher.Add(source); err != nil {
-			Warn(err.Error())
-		}
-	}
+	configureWatcher(watcher, files, dirs)
 }
 
 func Websocket(ctx *ink.Context) {