fix(chat): expire typing indicators by deadline instead of timestamp equality

On Windows the coarse clock can return the same time for two addTyper
calls, so a stale expiry matched the extended indicator and removed it
early. Compare the stored deadline against the current time instead.

internal/ui/chat/model.go

@@ -257,7 +257,7 @@ func (m *Model) Update(msg tview.Msg) tview.Cmd {
 	case messageslist.Msg:
 		return m.messagesList.Update(msg)
 	case typingExpiredMsg:
-		if m.typers[msg.userID] == msg.until {
+		if until, ok := m.typers[msg.userID]; ok && !time.Now().Before(until) {
 			m.removeTyper(msg.userID)
 		}
 		return nil
@@ -421,10 +421,9 @@ func (m *Model) View() tview.Element {
 	)
 }
 
-// typingExpiredMsg ends a user's typing indicator unless they typed again after it was set to expire at until.
+// typingExpiredMsg ends a user's typing indicator unless they typed again and extended it.
 type typingExpiredMsg struct {
 	userID discord.UserID
-	until  time.Time
 }
 
 func (m *Model) clearTypers() {
@@ -434,12 +433,11 @@ func (m *Model) clearTypers() {
 
 // addTyper shows userID as typing and returns a command that ends it after the typing duration.
 func (m *Model) addTyper(userID discord.UserID) tview.Cmd {
-	until := time.Now().Add(composer.TypingDuration)
+	m.typers[userID] = time.Now().Add(composer.TypingDuration)
-	m.typers[userID] = until
 	m.updateFooter()
 	return func() tview.Msg {
 		time.Sleep(composer.TypingDuration)
-		return typingExpiredMsg{userID, until}
+		return typingExpiredMsg{userID}
 	}
 }
 

internal/ui/chat/model_test.go

@@ -3,6 +3,7 @@ package chat
 import (
 	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/ayn2op/arikawa/v3/discord"
 	"github.com/ayn2op/arikawa/v3/gateway"
@@ -41,13 +42,13 @@ func TestModelUpdate(t *testing.T) {
 	t.Run("typing expires unless extended", func(t *testing.T) {
 		m := newTestModel(t)
 		m.addTyper(1)
-		first := m.typers[1]
 		m.addTyper(1)
-		m.Update(typingExpiredMsg{userID: 1, until: first})
+		m.Update(typingExpiredMsg{userID: 1})
 		if _, ok := m.typers[1]; !ok {
 			t.Fatal("an extended typing indicator expired early")
 		}
-		m.Update(typingExpiredMsg{userID: 1, until: m.typers[1]})
+		m.typers[1] = time.Now().Add(-time.Second)
+		m.Update(typingExpiredMsg{userID: 1})
 		if _, ok := m.typers[1]; ok {
 			t.Fatal("the typing indicator did not expire")
 		}