Java

src/java/tests/com/facebook/csslayout/LayoutCachingTest.java

@@ -0,0 +1,180 @@
+package com.facebook.csslayout;
+
+import org.junit.Test;
+
+import static junit.framework.Assert.*;
+
+/**
+ * Tests for {@link LayoutEngine} and {@link CSSNode} to make sure layouts are only generated when
+ * needed.
+ */
+public class LayoutCachingTest {
+
+  private void assertTreeHasNewLayout(boolean expectedHasNewLayout, CSSNode root) {
+    assertEquals(expectedHasNewLayout, root.hasNewLayout());
+
+    for (int i = 0; i < root.getChildCount(); i++) {
+      assertTreeHasNewLayout(expectedHasNewLayout, root.getChildAt(i));
+    }
+  }
+
+  private void markLayoutAppliedForTree(CSSNode root) {
+    root.markLayoutApplied();
+    for (int i = 0; i < root.getChildCount(); i++) {
+      markLayoutAppliedForTree(root.getChildAt(i));
+    }
+  }
+
+  @Test
+  public void testCachesFullTree() {
+    CSSNode root = new CSSNode();
+    CSSNode c0 = new CSSNode();
+    CSSNode c1 = new CSSNode();
+    CSSNode c0c0 = new CSSNode();
+    root.addChildAt(c0, 0);
+    root.addChildAt(c1, 1);
+    c0.addChildAt(c0c0, 0);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(true, root);
+    markLayoutAppliedForTree(root);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+  }
+
+  @Test
+  public void testInvalidatesCacheWhenChildAdded() {
+    CSSNode root = new CSSNode();
+    CSSNode c0 = new CSSNode();
+    CSSNode c1 = new CSSNode();
+    CSSNode c0c0 = new CSSNode();
+    CSSNode c0c1 = new CSSNode();
+    c0c1.setStyleWidth(200);
+    c0c1.setStyleHeight(200);
+    root.addChildAt(c0, 0);
+    root.addChildAt(c1, 1);
+    c0.addChildAt(c0c0, 0);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(true, root);
+    markLayoutAppliedForTree(root);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+
+    c0.addChildAt(c0c1, 1);
+
+    root.calculateLayout();
+    assertTrue(root.hasNewLayout());
+    assertTrue(c0.hasNewLayout());
+    assertTrue(c0c1.hasNewLayout());
+
+    assertFalse(c0c0.hasNewLayout());
+    assertFalse(c1.hasNewLayout());
+  }
+
+  @Test
+  public void testInvalidatesCacheWhenEnumPropertyChanges() {
+    CSSNode root = new CSSNode();
+    CSSNode c0 = new CSSNode();
+    CSSNode c1 = new CSSNode();
+    CSSNode c0c0 = new CSSNode();
+    root.addChildAt(c0, 0);
+    root.addChildAt(c1, 1);
+    c0.addChildAt(c0c0, 0);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(true, root);
+    markLayoutAppliedForTree(root);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+
+    c1.setAlignSelf(CSSAlign.CENTER);
+    root.calculateLayout();
+
+    assertTrue(root.hasNewLayout());
+    assertTrue(c1.hasNewLayout());
+
+    assertFalse(c0.hasNewLayout());
+    assertFalse(c0c0.hasNewLayout());
+  }
+
+  @Test
+  public void testInvalidatesCacheWhenFloatPropertyChanges() {
+    CSSNode root = new CSSNode();
+    CSSNode c0 = new CSSNode();
+    CSSNode c1 = new CSSNode();
+    CSSNode c0c0 = new CSSNode();
+    root.addChildAt(c0, 0);
+    root.addChildAt(c1, 1);
+    c0.addChildAt(c0c0, 0);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(true, root);
+    markLayoutAppliedForTree(root);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+
+    c1.setMarginLeft(10);
+    root.calculateLayout();
+
+    assertTrue(root.hasNewLayout());
+    assertTrue(c1.hasNewLayout());
+
+    assertFalse(c0.hasNewLayout());
+    assertFalse(c0c0.hasNewLayout());
+  }
+
+  @Test
+  public void testInvalidatesFullTreeWhenParentWidthChanges() {
+    CSSNode root = new CSSNode();
+    CSSNode c0 = new CSSNode();
+    CSSNode c1 = new CSSNode();
+    CSSNode c0c0 = new CSSNode();
+    root.addChildAt(c0, 0);
+    root.addChildAt(c1, 1);
+    c0.addChildAt(c0c0, 0);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(true, root);
+    markLayoutAppliedForTree(root);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+
+    c0.setStyleWidth(200);
+    root.calculateLayout();
+
+    assertTrue(root.hasNewLayout());
+    assertTrue(c0.hasNewLayout());
+    assertTrue(c0c0.hasNewLayout());
+
+    assertFalse(c1.hasNewLayout());
+  }
+
+  @Test
+  public void testDoesNotInvalidateCacheWhenPropertyIsTheSame() {
+    CSSNode root = new CSSNode();
+    CSSNode c0 = new CSSNode();
+    CSSNode c1 = new CSSNode();
+    CSSNode c0c0 = new CSSNode();
+    root.addChildAt(c0, 0);
+    root.addChildAt(c1, 1);
+    c0.addChildAt(c0c0, 0);
+    root.setStyleWidth(200);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(true, root);
+    markLayoutAppliedForTree(root);
+
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+
+    root.setStyleWidth(200);
+    root.calculateLayout();
+    assertTreeHasNewLayout(false, root);
+  }
+}