fix(gmail): guard watch retry rollback

vincentkoc · vincentkoc · commit a2d1d8f0cb4d · 2026-06-09T13:47:33.000+09:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## 0.23.1 - Unreleased
 
+### Added
+
+- Gmail: add `gmail watch pull` for Pub/Sub pull subscription consumers with hook retry support. (#700) — thanks @joshp123.
+
 ## 0.23.0 - 2026-06-09
 
 ### Added
diff --git a/docs/commands/README.md b/docs/commands/README.md
@@ -2,7 +2,7 @@
 
 Every `gog` command has a generated docs page. The source of truth is the live CLI schema; run `make docs-commands` after changing command names, flags, help text, aliases, or arguments.
 
-Generated pages: 588.
+Generated pages: 589.
 
 ## Top-level Commands
 
diff --git a/internal/cmd/gmail_watch_pull.go b/internal/cmd/gmail_watch_pull.go
@@ -299,7 +299,7 @@ func (s *gmailWatchServer) processGmailWatchPayload(ctx context.Context, payload
 	if err := s.sendHook(ctx, result); err != nil {
 		s.warnf("watch: hook failed: %v", err)
 		processed.HookFailed = true
-		if restoreErr := s.restoreWatchProgressForRetry(progressBefore); restoreErr != nil {
+		if restoreErr := s.restoreWatchProgressForRetry(progressBefore, result.HistoryID, payload.MessageID); restoreErr != nil {
 			s.warnf("watch: failed to preserve retry state after hook failure: %v", restoreErr)
 		}
 		return processed, &gmailWatchHookDeliveryError{Err: err}
@@ -324,11 +324,17 @@ func (e *gmailWatchHookDeliveryError) Unwrap() error {
 	return e.Err
 }
 
-func (s *gmailWatchServer) restoreWatchProgressForRetry(before gmailWatchState) error {
+func (s *gmailWatchServer) restoreWatchProgressForRetry(before gmailWatchState, historyID, pushMessageID string) error {
 	if s.store == nil {
 		return nil
 	}
 	return s.store.Update(func(state *gmailWatchState) error {
+		if state.HistoryID != historyID {
+			return nil
+		}
+		if pushMessageID != "" && state.LastPushMessageID != pushMessageID {
+			return nil
+		}
 		state.HistoryID = before.HistoryID
 		state.LastPushMessageID = before.LastPushMessageID
 		return nil
diff --git a/internal/cmd/gmail_watch_pull_test.go b/internal/cmd/gmail_watch_pull_test.go
@@ -233,6 +233,46 @@ func TestGmailWatchPullMessage_NacksHookFailureAndPreservesProgress(t *testing.T
 	}
 }
 
+func TestGmailWatchRestoreProgressForRetrySkipsNewerProgress(t *testing.T) {
+	setWatchTestConfigHome(t)
+
+	store, err := newGmailWatchStore("a@b.com")
+	if err != nil {
+		t.Fatalf("store: %v", err)
+	}
+	if updateErr := store.Update(func(s *gmailWatchState) error {
+		*s = gmailWatchState{
+			Account:           "a@b.com",
+			HistoryID:         "100",
+			LastPushMessageID: "msg-before",
+		}
+		return nil
+	}); updateErr != nil {
+		t.Fatalf("seed: %v", updateErr)
+	}
+	before := store.Get()
+	if updateErr := store.Update(func(s *gmailWatchState) error {
+		s.HistoryID = "300"
+		s.LastPushMessageID = "msg-newer"
+		return nil
+	}); updateErr != nil {
+		t.Fatalf("advance: %v", updateErr)
+	}
+
+	server := &gmailWatchServer{store: store}
+	if err := server.restoreWatchProgressForRetry(before, "200", "msg-failed"); err != nil {
+		t.Fatalf("restore: %v", err)
+	}
+
+	state := store.Get()
+	if state.HistoryID != "300" {
+		t.Fatalf("history id = %q", state.HistoryID)
+	}
+	if state.LastPushMessageID != "msg-newer" {
+		t.Fatalf("last push message id = %q", state.LastPushMessageID)
+	}
+}
+
 func TestGmailWatchPullMessage_RetriesHookFailureThenAcksSuccess(t *testing.T) {
 	server, hook, cleanup := newPullProcessorTestServer(t, http.StatusOK)
 	defer cleanup()
