Fix test to fail without the fix

modules/javafx.graphics/src/main/native-glass/gtk/glass_window.cpp

@@ -1114,7 +1114,6 @@ void WindowContextTop::set_bounds(int x, int y, bool xSet, bool ySet, int w, int
         newH = ch;
     }
 
-
     if (newW > 0 || newH > 0) {
         // call update_window_constraints() to let gtk_window_resize succeed, because it's bound to geometry constraints
         update_window_constraints();

tests/system/src/test/java/test/robot/javafx/stage/StageMixedSizeTest.java

@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2024 Oracle and/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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+package test.robot.javafx.stage;
+
+import javafx.animation.KeyFrame;
+import javafx.animation.Timeline;
+import javafx.geometry.Insets;
+import javafx.scene.Scene;
+import javafx.scene.layout.Background;
+import javafx.scene.layout.BackgroundFill;
+import javafx.scene.layout.CornerRadii;
+import javafx.scene.layout.Pane;
+import javafx.scene.paint.Color;
+import javafx.stage.Stage;
+import javafx.stage.StageStyle;
+import javafx.util.Duration;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+import test.robot.testharness.VisualTestBase;
+
+import java.util.Map;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static test.util.Util.TIMEOUT;
+
+public class StageMixedSizeTest extends VisualTestBase {
+    private static final Color BACKGROUND_COLOR = Color.YELLOW;
+    private static final double TOLERANCE = 0.07;
+    private Stage testStage;
+
+    @Test
+    public void testSetWidthOnlyAfterShownOnContentSizeWindow() throws Exception {
+        CountDownLatch latch = new CountDownLatch(1);
+        final int finalWidth = 200;
+
+        setupContentSizeTestStage(300, 300,
+                () -> doTimeLine(Map.of(500L, () -> testStage.setWidth(finalWidth),
+                                       1000L, latch::countDown)));
+
+        assertTrue(latch.await(TIMEOUT, TimeUnit.MILLISECONDS), "Timeout waiting for test stage to be shown");
+
+        runAndWait(() -> assertColorDoesNotEqual(BACKGROUND_COLOR, getColor(290, 100), TOLERANCE));
+        Assertions.assertEquals(finalWidth, testStage.getWidth(), "Window width should be " + finalWidth);
+    }
+
+    @Test
+    public void testSetHeightOnlyAfterShownOnContentSizeWindow() throws Exception {
+        CountDownLatch latch = new CountDownLatch(1);
+        final int finalHeight = 200;
+
+        setupContentSizeTestStage(300, 300,
+                () -> doTimeLine(Map.of(500L, () -> testStage.setHeight(finalHeight),
+                                       1000L, latch::countDown)));
+
+        assertTrue(latch.await(TIMEOUT, TimeUnit.MILLISECONDS), "Timeout waiting for test stage to be shown");
+
+        runAndWait(() -> assertColorDoesNotEqual(BACKGROUND_COLOR, getColor(100, 290), TOLERANCE));
+        Assertions.assertEquals(finalHeight, testStage.getHeight(), "Window height should be " + finalHeight);
+
+    }
+
+    private void setupContentSizeTestStage(int width, int height, Runnable onShown) {
+        runAndWait(() -> {
+            testStage = getStage(true);
+            testStage.initStyle(StageStyle.TRANSPARENT);
+            Pane pane = new Pane();
+            pane.setPrefSize(width, height);
+            pane.setBackground(new Background(new BackgroundFill(BACKGROUND_COLOR, CornerRadii.EMPTY, Insets.EMPTY)));
+            Scene scene = new Scene(pane);
+            testStage.setScene(scene);
+            testStage.setX(0);
+            testStage.setY(0);
+            testStage.setOnShown(e -> onShown.run());
+            testStage.show();
+        });
+    }
+
+
+    private void doTimeLine(Map<Long, Runnable> keyFrames) {
+        Timeline timeline = new Timeline();
+        timeline.setCycleCount(1);
+        keyFrames.forEach((duration, runnable) ->
+                timeline.getKeyFrames().add(new KeyFrame(Duration.millis(duration), e -> runnable.run())));
+        timeline.play();
+    }
+}