fix: improve appendToolCallStatus method to handle non-error statuses correctly

Author: jdneo

com.microsoft.copilot.eclipse.ui.test/src/com/microsoft/copilot/eclipse/ui/chat/BaseTurnWidgetToolCallStatusTest.java

@@ -181,6 +181,30 @@ void appendToolCallStatus_errorFallsBackToProgressMessage_whenErrorIsNull() {
     });
   }
 
+  @Test
+  void appendToolCallStatus_nonErrorStatusWithOnlyError_isIgnored() {
+    SwtUtils.invokeOnDisplayThread(() -> {
+      try (MockedStatic<CopilotUi> copilotUiMock = mockStatic(CopilotUi.class)) {
+        CopilotUi mockPlugin = mock(CopilotUi.class);
+        copilotUiMock.when(CopilotUi::getPlugin).thenReturn(mockPlugin);
+        lenient().when(mockPlugin.getChatServiceManager()).thenReturn(mockChatServiceManager);
+
+        CopilotTurnWidget widget = new CopilotTurnWidget(shell, SWT.NONE, mockChatServiceManager, TURN_ID);
+
+        // Non-error events with only `error` populated must be dropped; otherwise
+        // setRunningStatus/setCompletedStatus/setText would call setMarkup(null).
+        widget.appendToolCallStatus(buildToolCall("running", null, ERROR_MESSAGE));
+        widget.appendToolCallStatus(buildToolCall("completed", "   ", ERROR_MESSAGE));
+        widget.appendToolCallStatus(buildToolCall("cancelled", null, ERROR_MESSAGE));
+
+        @SuppressWarnings("unchecked")
+        Map<String, AgentStatusLabel> labels = (Map<String, AgentStatusLabel>) getField(widget, "statusLabels");
+        assertTrue(labels.isEmpty(),
+            "Non-error events without progressMessage should be ignored, got: " + labels.keySet());
+      }
+    });
+  }
+
   private static AgentToolCall buildToolCall(String status, String progressMessage, String error) {
     Gson gson = new Gson();
     java.util.Map<String, Object> fields = new java.util.HashMap<>();

com.microsoft.copilot.eclipse.ui/src/com/microsoft/copilot/eclipse/ui/chat/BaseTurnWidget.java

@@ -226,8 +226,16 @@ public void appendMessage(String message) {
    * @param toolCall the tool call of the agent turn
    */
   public void appendToolCallStatus(AgentToolCall toolCall) {
-    if (toolCall == null
-        || (StringUtils.isBlank(toolCall.getProgressMessage()) && StringUtils.isBlank(toolCall.getError()))) {
+    if (toolCall == null || toolCall.getStatus() == null) {
+      return;
+    }
+
+    String status = toolCall.getStatus().toLowerCase();
+    // Require a non-blank progressMessage for non-error events. For error events,
+    // also accept a non-blank `error` field as the displayable text.
+    boolean isError = "error".equals(status);
+    if (StringUtils.isBlank(toolCall.getProgressMessage())
+        && (!isError || StringUtils.isBlank(toolCall.getError()))) {
       return;
     }
 
@@ -255,7 +263,6 @@ public void appendToolCallStatus(AgentToolCall toolCall) {
     AgentStatusLabel statusLabel = statusLabels.computeIfAbsent(toolCall.getId(),
         id -> new AgentStatusLabel(this, SWT.LEFT));
 
-    String status = toolCall.getStatus().toLowerCase();
     switch (status) {
       case "running":
         statusLabel.setRunningStatus(toolCall.getProgressMessage());