Merge pull request #643 from peco/fix-input-alt-key-race

Handle esc in the input loop as well

input.go

@@ -11,9 +11,10 @@ import (
 
 func NewInput(state *Peco, am ActionMap, src chan Event) *Input {
 	return &Input{
-		actions: am,
-		evsrc:   src,
-		state:   state,
+		actions:    am,
+		evsrc:      src,
+		pendingEsc: make(chan Event, 1),
+		state:      state,
 	}
 }
 
@@ -24,6 +25,11 @@ func (i *Input) Loop(ctx context.Context, cancel func()) error {
 		select {
 		case <-ctx.Done():
 			return nil
+		case ev := <-i.pendingEsc:
+			// Timer fired and determined this was a standalone Esc press.
+			// Execute the action here on the input loop goroutine, not
+			// on the timer goroutine, to avoid concurrent ExecuteAction calls.
+			i.state.Keymap().ExecuteAction(ctx, i.state, ev)
 		case ev, ok := <-i.evsrc:
 			if !ok {
 				return nil
@@ -73,7 +79,13 @@ func (i *Input) handleInputEvent(ctx context.Context, ev Event) error {
 				}
 				i.mod = nil
 				m.Unlock()
-				i.state.Keymap().ExecuteAction(ctx, i.state, tmp)
+				// Send to the input loop instead of calling ExecuteAction
+				// directly, so all action execution is serialized on the
+				// input loop goroutine.
+				select {
+				case i.pendingEsc <- tmp:
+				case <-ctx.Done():
+				}
 			})
 			m.Unlock()
 			return nil

input_test.go

@@ -85,9 +85,23 @@ func TestInputModifierKeyRace(t *testing.T) {
 		state.config.Action = map[string][]string{}
 		require.NoError(t, state.populateKeymap())
 
-		ctx := context.Background()
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
 		input := NewInput(state, state.Keymap(), make(chan Event))
 
+		// Start a goroutine that drains pendingEsc and executes actions,
+		// simulating what Loop does.
+		go func() {
+			for {
+				select {
+				case <-ctx.Done():
+					return
+				case ev := <-input.pendingEsc:
+					input.state.Keymap().ExecuteAction(ctx, input.state, ev)
+				}
+			}
+		}()
+
 		// Send Esc event — starts the 50ms timer
 		escEv := Event{Type: EventKey, Key: keyseq.KeyEsc, Ch: 0}
 		input.handleInputEvent(ctx, escEv)

interface.go

@@ -504,14 +504,15 @@ type ActionMap interface {
 }
 
 type Input struct {
-	actions ActionMap
-	evsrc   chan Event
-	mod     *time.Timer
-	modGen  uint64 // generation counter to invalidate stale timer callbacks.
+	actions    ActionMap
+	evsrc      chan Event
+	pendingEsc chan Event // receives Esc events from the timer callback
+	mod        *time.Timer
+	modGen     uint64 // generation counter to invalidate stale timer callbacks.
 	// uint64 holds up to ~1.8×10¹⁹. At most 2 increments per Esc key event
 	// and a generous 100 keystrokes/second, overflow would take ~2.9 trillion years.
-	mutex   sync.Mutex
-	state   *Peco
+	mutex sync.Mutex
+	state *Peco
 }
 
 // HubSender provides methods for sending messages to the hub.