8373967: [macos] User interactions with List do not trigger ItemEvent after programmatic change

Reviewed-by: azvegint

Author: mrserb

src/java.desktop/macosx/classes/sun/lwawt/LWListPeer.java

@@ -49,6 +49,10 @@
 import javax.swing.event.ListSelectionEvent;
 import javax.swing.event.ListSelectionListener;
 
+import static java.awt.event.ItemEvent.DESELECTED;
+import static java.awt.event.ItemEvent.ITEM_STATE_CHANGED;
+import static java.awt.event.ItemEvent.SELECTED;
+
 /**
  * Lightweight implementation of {@link ListPeer}. Delegates most of the work to
  * the {@link JList}, which is placed inside {@link JScrollPane}.
@@ -280,21 +284,18 @@ public void setSkipStateChangedEvent(boolean skipStateChangedEvent) {
 
         @Override
         public void valueChanged(final ListSelectionEvent e) {
-            if (!e.getValueIsAdjusting() && !isSkipStateChangedEvent()) {
-                final JList<?> source = (JList<?>) e.getSource();
-                for(int i = 0 ; i < source.getModel().getSize(); i++) {
-
-                    final boolean wasSelected = Arrays.binarySearch(oldSelectedIndices, i) >= 0;
-                    final boolean isSelected = source.isSelectedIndex(i);
-
-                    if (wasSelected == isSelected) {
-                        continue;
+            if (!e.getValueIsAdjusting()) {
+                JList<?> source = (JList<?>) e.getSource();
+                if (!isSkipStateChangedEvent()) {
+                    for (int i = 0; i < source.getModel().getSize(); i++) {
+                        boolean wasSelected =
+                                Arrays.binarySearch(oldSelectedIndices, i) >= 0;
+                        if (wasSelected != source.isSelectedIndex(i)) {
+                            int state = wasSelected ? DESELECTED : SELECTED;
+                            LWListPeer.this.postEvent(new ItemEvent(getTarget(),
+                                                ITEM_STATE_CHANGED, i, state));
+                        }
                     }
-
-                    final int state = !wasSelected && isSelected ? ItemEvent.SELECTED: ItemEvent.DESELECTED;
-
-                    LWListPeer.this.postEvent(new ItemEvent(getTarget(), ItemEvent.ITEM_STATE_CHANGED,
-                            i, state));
                 }
                 oldSelectedIndices = source.getSelectedIndices();
             }

test/jdk/java/awt/List/NoEvents/MixProgrammaticUserChange.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.awt.Frame;
+import java.awt.List;
+import java.awt.Point;
+import java.awt.Robot;
+import java.awt.event.ItemEvent;
+import java.awt.event.KeyEvent;
+import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.TimeUnit;
+
+import jdk.test.lib.Platform;
+
+/**
+ * @test
+ * @bug 8373967
+ * @key headful
+ * @summary Checks that programmatic changes to a List do not fire events,
+ *          only user interactions do
+ * @library /test/lib
+ * @build jdk.test.lib.Platform
+ * @run main/othervm MixProgrammaticUserChange
+ */
+public final class MixProgrammaticUserChange {
+
+    private static Robot robot;
+    private static final BlockingQueue<ItemEvent> events =
+            new ArrayBlockingQueue<>(10);
+
+    public static void main(String[] args) throws Exception {
+        Frame frame = new Frame();
+        try {
+            robot = new Robot();
+            robot.setAutoWaitForIdle(true);
+            robot.setAutoDelay(100);
+
+            List list = new List(1, true);
+            list.add("Item");
+            list.addItemListener(e -> {
+                if (e.getID() == ItemEvent.ITEM_STATE_CHANGED) {
+                    events.offer(e);
+                }
+            });
+
+            frame.add(list);
+            frame.setUndecorated(true);
+            frame.pack();
+            frame.setLocationRelativeTo(null);
+            frame.setVisible(true);
+            robot.waitForIdle(100);
+
+            Point loc = list.getLocationOnScreen();
+            loc.translate(list.getWidth() / 2, list.getHeight() / 2);
+
+            test(() -> click(loc), ItemEvent.SELECTED);
+            test(() -> list.deselect(0), -1);
+            test(() -> click(loc), ItemEvent.SELECTED);
+            test(() -> click(loc), ItemEvent.DESELECTED);
+            test(() -> list.select(0), -1);
+            test(() -> click(loc), ItemEvent.DESELECTED);
+        } finally {
+            frame.dispose();
+        }
+        if (!events.isEmpty()) {
+            throw new RuntimeException("Unexpected events: " + events);
+        }
+    }
+
+    private static void test(Runnable action, int state) throws Exception {
+        action.run();
+        // Large delay, we are waiting for unexpected events
+        ItemEvent e = events.poll(1, TimeUnit.SECONDS);
+        if (e == null && state == -1) {
+            return; // no events as expected
+        } else if (e != null && e.getStateChange() == state) {
+            return; // expected event received
+        }
+        String text = (state == -1) ? "null" : state == ItemEvent.SELECTED
+                                             ? "SELECTED" : "DESELECTED";
+        throw new RuntimeException("Expected: %s, got: %s".formatted(text, e));
+    }
+
+    private static void click(Point p) {
+        robot.mouseMove(p.x, p.y);
+        int keyCode = Platform.isOSX() ? KeyEvent.VK_META : KeyEvent.VK_CONTROL;
+        robot.keyPress(keyCode);
+        try {
+            robot.click();
+        } finally {
+            robot.keyRelease(keyCode);
+        }
+    }
+}