Initialize clipboard asynchronously to avoid startup delay in WSL2

cmd/micro/micro.go

@@ -370,7 +370,7 @@ func main() {
 	signal.Notify(sighup, syscall.SIGHUP)
 
 	m := clipboard.SetMethod(config.GetGlobalOption("clipboard").(string))
-	clipErr := clipboard.Initialize(m)
+	clipboard.InitAsync(m)
 
 	defer func() {
 		if err := recover(); err != nil {
@@ -441,10 +441,6 @@ func main() {
 		screen.TermMessage(err)
 	}
 
-	if clipErr != nil {
-		log.Println(clipErr, " or change 'clipboard' option")
-	}
-
 	config.StartAutoSave()
 	if a := config.GetGlobalOption("autosave").(float64); a > 0 {
 		config.SetAutoTime(a)

internal/clipboard/clipboard.go

@@ -2,6 +2,8 @@ package clipboard
 
 import (
 	"errors"
+	"log"
+	"sync"
 
 	"github.com/zyedidia/clipper"
 )
@@ -37,6 +39,11 @@ const (
 
 var clipboard clipper.Clipboard
 
+var (
+	initDone   = make(chan struct{})
+	initClosed sync.Once
+)
+
 // Initialize attempts to initialize the clipboard using the given method
 func Initialize(m Method) error {
 	var err error
@@ -52,9 +59,19 @@ func Initialize(m Method) error {
 	if err != nil {
 		CurrentMethod = Internal
 	}
+	initClosed.Do(func() { close(initDone) })
 	return err
 }
 
+// InitAsync runs Initialize in a background goroutine
+func InitAsync(m Method) {
+	go func() {
+		if err := Initialize(m); err != nil {
+			log.Println(err, " or change 'clipboard' option")
+		}
+	}()
+}
+
 // SetMethod changes the clipboard access method
 func SetMethod(m string) Method {
 	switch m {
@@ -70,11 +87,13 @@ func SetMethod(m string) Method {
 
 // Read reads from a clipboard register
 func Read(r Register) (string, error) {
+	<-initDone
 	return read(r, CurrentMethod)
 }
 
 // Write writes text to a clipboard register
 func Write(text string, r Register) error {
+	<-initDone
 	return write(text, r, CurrentMethod)
 }
 
@@ -92,6 +111,7 @@ func ReadMulti(r Register, num, ncursors int) (string, error) {
 
 // WriteMulti writes text to a clipboard register for a certain multi-cursor
 func WriteMulti(text string, r Register, num int, ncursors int) error {
+	<-initDone
 	return writeMulti(text, r, num, ncursors, CurrentMethod)
 }