fix(client): preserve terminal watch outcomes

submitqueue/client/history_read_test.go

@@ -44,6 +44,35 @@ func (f historySourceFunc) GetRequestHistoryByID(
 	return f(ctx, request)
 }
 
+func TestHistoryLateEventsPreserveTerminalOutcome(t *testing.T) {
+	for _, terminal := range []string{"landed", "cancelled", "error"} {
+		for _, late := range []*pb.HistoryEvent{{Status: "cancelling"}, {Event: "built"}} {
+			t.Run(terminal+"/"+late.Status+late.Event, func(t *testing.T) {
+				note := ""
+				if terminal == "error" {
+					note = "merge conflict"
+				}
+				row := &Row{SQID: "42"}
+				tracker := NewTracker([]*Row{row})
+				reader := historyReaderFunc(func(context.Context, string, string) ([]*pb.HistoryEvent, error) {
+					return []*pb.HistoryEvent{{Status: terminal, LastError: note}, late}, nil
+				})
+				captureStdout(t, func() {
+					tracker.Seal()
+					require.NoError(t, tracker.refreshHistory(context.Background(), reader, "queue", true))
+				})
+				assert.Equal(t, terminal, row.Status)
+				assert.Equal(t, note, row.Note)
+				assert.True(t, row.Done)
+				assert.True(t, isClosed(tracker.Settled()))
+				if terminal == "landed" {
+					assert.NoError(t, summarize([]*Row{row}))
+				}
+			})
+		}
+	}
+}
+
 func TestPollHistoryPermanentFailures(t *testing.T) {
 	for _, code := range []codes.Code{codes.PermissionDenied, codes.Unauthenticated, codes.InvalidArgument} {
 		t.Run(code.String(), func(t *testing.T) {

submitqueue/client/view.go

@@ -148,8 +148,8 @@ func Draw(rows []*Row, status string) {
 }
 
 // digest reduces a request's recorded history to the trail worth showing, the
-// status it currently holds, and the error the latest event carried. A status
-// recorded more than once in a row is one step in the trail, not several.
+// status it currently holds, and its diagnostic. Terminal outcomes take precedence
+// over later nonterminal entries. Consecutive repeated statuses form one trail step.
 //
 // The history holds two kinds of entry. A status is a position the request
 // reached, and those are the trail's spine. An event is something that happened
@@ -193,13 +193,17 @@ func digest(events []*pb.HistoryEvent) (trail []string, status, note string) {
 	}
 
 	for _, e := range events {
-		if e == nil {
+		if e == nil || (e.Status == "" && e.Event == "") {
 			continue
 		}
-		if e.Status == "" {
-			if e.Event == "" {
-				continue
+		// Late cancellation intents and background work cannot reopen a settled request.
+		if !terminalStatuses[status] || terminalStatuses[e.Status] {
+			if e.Status != "" {
+				status = e.Status
 			}
+			note = e.LastError
+		}
+		if e.Status == "" {
 			if counts[e.Event] == 0 {
 				pending = append(pending, e.Event)
 			}
@@ -217,13 +221,6 @@ func digest(events []*pb.HistoryEvent) (trail []string, status, note string) {
 	}
 	flush()
 
-	if last := events[len(events)-1]; last != nil {
-		status, note = last.Status, last.LastError
-	}
-	// The last entry may be an event, which leaves the request where it was.
-	if status == "" {
-		status = currentStatus(events)
-	}
 	return trail, status, note
 }
 
@@ -241,17 +238,6 @@ func annotate(order []string, counts map[string]int) []string {
 	return out
 }
 
-// currentStatus is the last position the request reached, ignoring anything
-// recorded while it sat there.
-func currentStatus(events []*pb.HistoryEvent) string {
-	for i := len(events) - 1; i >= 0; i-- {
-		if e := events[i]; e != nil && e.Status != "" {
-			return e.Status
-		}
-	}
-	return ""
-}
-
 // outcome is the one-line verdict shown under the finished table.
 func outcome(rows []*Row) string {
 	landed := 0

submitqueue/client/view_test.go

@@ -169,6 +169,34 @@ func TestDigest(t *testing.T) {
 			wantStatus: "speculating",
 			wantNote:   "runner unreachable",
 		},
+		{
+			name: "a late cancellation stays in the trail without reopening a landed request",
+			events: []*pb.HistoryEvent{
+				{Status: "landed"}, {Status: "cancelling"},
+			},
+			wantTrail:  []string{"landed", "cancelling"},
+			wantStatus: "landed",
+		},
+		{
+			name: "background work cannot replace a terminal failure reason",
+			events: []*pb.HistoryEvent{
+				{Status: "error", LastError: "merge conflict"},
+				{Event: "built", LastError: "unused build failed"},
+			},
+			wantTrail:  []string{"error [after: built]"},
+			wantStatus: "error",
+			wantNote:   "merge conflict",
+		},
+		{
+			name: "a repeated terminal status updates its diagnostic",
+			events: []*pb.HistoryEvent{
+				{Status: "error", LastError: "failed"}, {Status: "cancelling"},
+				{Status: "error", LastError: "merge conflict"},
+			},
+			wantTrail:  []string{"error", "cancelling", "error"},
+			wantStatus: "error",
+			wantNote:   "merge conflict",
+		},
 	}
 
 	for _, tt := range tests {