Use Cut, Fields.

cmd/zenity/main.go

@@ -741,12 +741,12 @@ func addColumn(s string) error {
 func addFileFilter(s string) error {
 	var filter zenity.FileFilter
 
-	if head, tail, cut := strings.Cut(s, "|"); cut {
-		filter.Name = head
-		s = tail
+	if name, rest, cut := strings.Cut(s, "|"); cut {
+		filter.Name = name
+		s = rest
 	}
 
-	filter.Patterns = strings.Split(strings.Trim(s, " "), " ")
+	filter.Patterns = strings.Fields(s)
 	fileFilters = append(fileFilters, filter)
 	return nil
 }

cmd/zenity/notify.go

@@ -25,14 +25,13 @@ func notify(opts ...zenity.Option) error {
 	ico := zenity.NoIcon
 	for scanner := bufio.NewScanner(os.Stdin); scanner.Scan(); {
 		line := scanner.Text()
-		var cmd, msg string
-		if n := strings.IndexByte(line, ':'); n >= 0 {
-			cmd = strings.TrimSpace(line[:n])
-			msg = strings.TrimSpace(zencmd.Unescape(line[n+1:]))
-		} else {
+		cmd, msg, cut := strings.Cut(line, ":")
+		if !cut {
 			os.Stderr.WriteString("Could not parse command from stdin\n")
 			continue
 		}
+		cmd = strings.TrimSpace(cmd)
+		msg = strings.TrimSpace(zencmd.Unescape(msg))
 		switch cmd {
 		case "icon":
 			switch msg {
@@ -51,9 +50,9 @@ func notify(opts ...zenity.Option) error {
 			}
 		case "message", "tooltip":
 			opts := []zenity.Option{ico}
-			if n := strings.IndexByte(msg, '\n'); n >= 0 {
-				opts = append(opts, zenity.Title(msg[:n]))
-				msg = msg[n+1:]
+			if title, rest, cut := strings.Cut(msg, "\n"); cut {
+				opts = append(opts, zenity.Title(title))
+				msg = rest
 			}
 			if err := zenity.Notify(msg, opts...); err != nil {
 				return err

internal/win/ole32.go

@@ -60,5 +60,6 @@ type IBindCtx struct{ IUnknown }
 //sys CoCreateInstance(clsid *GUID, unkOuter *IUnknown, clsContext int32, iid *GUID, address unsafe.Pointer) (res error) = ole32.CoCreateInstance
 
 func guid(s string) *GUID {
+	// TODO: use unsafe.StringData after 1.20
 	return (*GUID)(unsafe.Pointer((*reflect.StringHeader)(unsafe.Pointer(&s)).Data))
 }

internal/zencmd/window_unix.go

@@ -92,12 +92,10 @@ func getWindowIDs() ([]string, error) {
 		return nil, err
 	}
 
-	if i := bytes.IndexByte(out, '\t'); i < 0 {
-		return nil, fmt.Errorf("xprop: unexpected output: %q", out)
-	} else {
-		out = out[i+1:]
-	}
+	if _, out, cut := bytes.Cut(out, []byte("\t")); cut {
 		return strings.Split(string(out), ", "), nil
+	}
+	return nil, fmt.Errorf("xprop: unexpected output: %q", out)
 }
 
 func getWindowPid(id string) (int, error) {
@@ -106,10 +104,8 @@ func getWindowPid(id string) (int, error) {
 		return 0, err
 	}
 
-	if i := bytes.IndexByte(out, '\t'); i < 0 {
-		return 0, fmt.Errorf("xprop: unexpected output: %q", out)
-	} else {
-		out = out[i+1:]
-	}
+	if _, out, cut := bytes.Cut(out, []byte("\t")); cut {
 		return strconv.Atoi(string(out))
+	}
+	return 0, fmt.Errorf("xprop: unexpected output: %q", out)
 }

internal/zenutil/osa_generator.go

@@ -33,7 +33,7 @@ func main() {
 		if err != nil {
 			log.Fatal(err)
 		}
-		if bytes.ContainsAny(data, "`") {
+		if bytes.ContainsRune(data, '`') {
 			log.Fatalf("illegal character: %s: `", name)
 		}
 		_, err = template.New(file.Name()).Funcs(funcs).Parse(string(data))

notify_darwin.go

@@ -8,13 +8,14 @@ import (
 
 func notify(text string, opts options) error {
 	var data zenutil.Notify
-	data.Text = text
 	data.Options.Title = opts.title
-
-	if i := strings.IndexByte(text, '\n'); i >= 0 && i < len(text) {
-		data.Options.Subtitle = text[:i]
-		data.Text = text[i+1:]
+	if sub, body, cut := strings.Cut(text, "\n"); cut {
+		data.Options.Subtitle = sub
+		data.Text = body
+	} else {
+		data.Text = text
 	}
+
 	_, err := zenutil.Run(opts.ctx, "notify", data)
 	if err != nil {
 		return err