internal/shaderlister: enable to specify multiple patterns

Updates #3157

internal/shaderlister/main.go

@@ -188,7 +188,7 @@ const (
 
 var (
 	reShaderSourceDirective = regexp.MustCompile(`(?m)^\s*//` + regexp.QuoteMeta(shaderSourceDirective) + `$`)
-	reShaderFileDirective   = regexp.MustCompile(`(?m)^\s*//` + regexp.QuoteMeta(shaderFileDirective) + ` (.+)$`)
+	reShaderFileDirective   = regexp.MustCompile(`(?m)^\s*//` + regexp.QuoteMeta(shaderFileDirective) + ` `)
 )
 
 func hasShaderSourceDirectiveInComment(commentGroup *ast.CommentGroup) bool {
@@ -200,6 +200,10 @@ func hasShaderSourceDirectiveInComment(commentGroup *ast.CommentGroup) bool {
 	return false
 }
 
+func isAsciiSpace(r rune) bool {
+	return r == ' ' || r == '\t' || r == '\v' || r == '\n' || r == '\r'
+}
+
 func appendShaderSources(shaders []Shader, pkg *packages.Package) ([]Shader, error) {
 	topLevelDecls := map[ast.Decl]struct{}{}
 	for _, file := range pkg.Syntax {
@@ -213,14 +217,22 @@ func appendShaderSources(shaders []Shader, pkg *packages.Package) ([]Shader, err
 	}
 
 	// Resolve ebitengine:shaderfile directives.
+	visitedPatterns := map[string]struct{}{}
+	visitedPaths := map[string]struct{}{}
 	for _, f := range pkg.Syntax {
 		for _, c := range f.Comments {
 			for _, l := range c.List {
-				m := reShaderFileDirective.FindStringSubmatch(l.Text)
-				if len(m) == 0 {
+				m := reShaderFileDirective.FindString(l.Text)
+				if m == "" {
 					continue
 				}
-				pattern := filepath.Join(pkg.Dir, filepath.FromSlash(m[1]))
+				patterns := strings.TrimPrefix(l.Text, m)
+				for _, pattern := range strings.FieldsFunc(patterns, isAsciiSpace) {
+					pattern := filepath.Join(pkg.Dir, filepath.FromSlash(pattern))
+					if _, ok := visitedPatterns[pattern]; ok {
+						continue
+					}
+					visitedPatterns[pattern] = struct{}{}
 					stat, err := os.Stat(pattern)
 					if err == nil && stat.IsDir() {
 						// If the pattern is a directory, read all files in the directory recursively.
@@ -231,6 +243,10 @@ func appendShaderSources(shaders []Shader, pkg *packages.Package) ([]Shader, err
 							if d.IsDir() {
 								return nil
 							}
+							if _, ok := visitedPaths[path]; ok {
+								return nil
+							}
+							visitedPaths[path] = struct{}{}
 							shaders, err = appendShaderFromFile(shaders, pkg.PkgPath, path)
 							if err != nil {
 								return err
@@ -249,6 +265,10 @@ func appendShaderSources(shaders []Shader, pkg *packages.Package) ([]Shader, err
 						return nil, err
 					}
 					for _, path := range paths {
+						if _, ok := visitedPaths[path]; ok {
+							continue
+						}
+						visitedPaths[path] = struct{}{}
 						shaders, err = appendShaderFromFile(shaders, pkg.PkgPath, path)
 						if err != nil {
 							return nil, err
@@ -257,6 +277,7 @@ func appendShaderSources(shaders []Shader, pkg *packages.Package) ([]Shader, err
 				}
 			}
 		}
+	}
 
 	// Resolve ebitengine:shadersource directives.
 	var genDeclStack []*ast.GenDecl

internal/shaderlister/shaderlistertest/def.go

@@ -69,7 +69,9 @@ const (
 	_, _ = "ignored", "ignored again" // multiple consts are ignored to avoid confusion.
 )
 
-//ebitengine:shaderfile *_kage.go
-//ebitengine:shaderfile resource
+//ebitengine:shaderfile *_kage.go resource nonexistent.go
+
+// Duplicated files are ignored.
+//ebitengine:shaderfile *_kage.go *_kage.go *_kage.go
 
 //ebitengine:shaderfile nonexistent.go