Make it so that aspect ratio behaves like auto if it is 0 or inf

gentest/fixtures/YGAspectRatioTest.html

@@ -2,14 +2,18 @@
 <div id="aspect_ratio_does_not_stretch_cross_axis_dim" data-disabled="true" style="width: 300px; height: 300px;">
   <div style="flex: 1; overflow: scroll;">
     <div style="flex-direction: row;">
-        <div style="flex: 2; aspect-ratio: 1;"></div>
-        <div style="width: 5px"></div>
-        <div style="flex: 1">
-          <div style="flex: 1; aspect-ratio: 1;">
+      <div style="flex: 2; aspect-ratio: 1;"></div>
+      <div style="width: 5px"></div>
+      <div style="flex: 1">
+        <div style="flex: 1; aspect-ratio: 1;">
           <div style="width: 5px"></div>
           <div style="flex: 1; aspect-ratio: 1;"></div>
         </div>
       </div>
     </div>
   </div>
 </div>
+
+<div id="zero_aspect_ratio_behaves_like_auto" style="width: 300px; height: 300px;">
+  <div style="aspect-ratio: 0; width: 50px"></div>
+</div>

java/tests/generated/com/facebook/yoga/YGAspectRatioTest.java

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<e5092fdd5b7f67021254ae2bbc5a3684>>
+ * @generated SignedSource<<37a01c67158df025b1b43b8378071746>>
  * generated by gentest/gentest-driver.ts from gentest/fixtures/YGAspectRatioTest.html
  */
 
@@ -179,6 +179,46 @@ public void test_aspect_ratio_does_not_stretch_cross_axis_dim() {
     assertEquals(197f, root_child0_child0_child2_child0_child1.getLayoutHeight(), 0.0f);
   }
 
+  @Test
+  public void test_zero_aspect_ratio_behaves_like_auto() {
+    YogaConfig config = YogaConfigFactory.create();
+
+    final YogaNode root = createNode(config);
+    root.setPositionType(YogaPositionType.ABSOLUTE);
+    root.setWidth(300f);
+    root.setHeight(300f);
+
+    final YogaNode root_child0 = createNode(config);
+    root_child0.setWidth(50f);
+    root_child0.setAspectRatio(0 / 1f);
+    root.addChildAt(root_child0, 0);
+    root.setDirection(YogaDirection.LTR);
+    root.calculateLayout(YogaConstants.UNDEFINED, YogaConstants.UNDEFINED);
+
+    assertEquals(0f, root.getLayoutX(), 0.0f);
+    assertEquals(0f, root.getLayoutY(), 0.0f);
+    assertEquals(300f, root.getLayoutWidth(), 0.0f);
+    assertEquals(300f, root.getLayoutHeight(), 0.0f);
+
+    assertEquals(0f, root_child0.getLayoutX(), 0.0f);
+    assertEquals(0f, root_child0.getLayoutY(), 0.0f);
+    assertEquals(50f, root_child0.getLayoutWidth(), 0.0f);
+    assertEquals(0f, root_child0.getLayoutHeight(), 0.0f);
+
+    root.setDirection(YogaDirection.RTL);
+    root.calculateLayout(YogaConstants.UNDEFINED, YogaConstants.UNDEFINED);
+
+    assertEquals(0f, root.getLayoutX(), 0.0f);
+    assertEquals(0f, root.getLayoutY(), 0.0f);
+    assertEquals(300f, root.getLayoutWidth(), 0.0f);
+    assertEquals(300f, root.getLayoutHeight(), 0.0f);
+
+    assertEquals(250f, root_child0.getLayoutX(), 0.0f);
+    assertEquals(0f, root_child0.getLayoutY(), 0.0f);
+    assertEquals(50f, root_child0.getLayoutWidth(), 0.0f);
+    assertEquals(0f, root_child0.getLayoutHeight(), 0.0f);
+  }
+
   private YogaNode createNode(YogaConfig config) {
     return mNodeFactory.create(config);
   }

javascript/tests/generated/YGAspectRatioTest.test.ts

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<acd05459fdaeace7681295ee1812c3cb>>
+ * @generated SignedSource<<c9a86707a0d8554afa020ec319688655>>
  * generated by gentest/gentest-driver.ts from gentest/fixtures/YGAspectRatioTest.html
  */
 
@@ -183,3 +183,48 @@ test.skip('aspect_ratio_does_not_stretch_cross_axis_dim', () => {
     config.free();
   }
 });
+test('zero_aspect_ratio_behaves_like_auto', () => {
+  const config = Yoga.Config.create();
+  let root;
+
+  try {
+    root = Yoga.Node.create(config);
+    root.setPositionType(PositionType.Absolute);
+    root.setWidth(300);
+    root.setHeight(300);
+
+    const root_child0 = Yoga.Node.create(config);
+    root_child0.setWidth(50);
+    root_child0.setAspectRatio(0 / 1);
+    root.insertChild(root_child0, 0);
+    root.calculateLayout(undefined, undefined, Direction.LTR);
+
+    expect(root.getComputedLeft()).toBe(0);
+    expect(root.getComputedTop()).toBe(0);
+    expect(root.getComputedWidth()).toBe(300);
+    expect(root.getComputedHeight()).toBe(300);
+
+    expect(root_child0.getComputedLeft()).toBe(0);
+    expect(root_child0.getComputedTop()).toBe(0);
+    expect(root_child0.getComputedWidth()).toBe(50);
+    expect(root_child0.getComputedHeight()).toBe(0);
+
+    root.calculateLayout(undefined, undefined, Direction.RTL);
+
+    expect(root.getComputedLeft()).toBe(0);
+    expect(root.getComputedTop()).toBe(0);
+    expect(root.getComputedWidth()).toBe(300);
+    expect(root.getComputedHeight()).toBe(300);
+
+    expect(root_child0.getComputedLeft()).toBe(250);
+    expect(root_child0.getComputedTop()).toBe(0);
+    expect(root_child0.getComputedWidth()).toBe(50);
+    expect(root_child0.getComputedHeight()).toBe(0);
+  } finally {
+    if (typeof root !== 'undefined') {
+      root.freeRecursive();
+    }
+
+    config.free();
+  }
+});

tests/generated/YGAspectRatioTest.cpp

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  *
  * clang-format off
- * @generated SignedSource<<bca5b9517b7a728b30eb070a33de0bdf>>
+ * @generated SignedSource<<0894aa78d01d5194e4c042491128cd1c>>
  * generated by gentest/gentest-driver.ts from gentest/fixtures/YGAspectRatioTest.html
  */
 
@@ -166,3 +166,44 @@ TEST(YogaTest, aspect_ratio_does_not_stretch_cross_axis_dim) {
 
   YGConfigFree(config);
 }
+
+TEST(YogaTest, zero_aspect_ratio_behaves_like_auto) {
+  YGConfigRef config = YGConfigNew();
+
+  YGNodeRef root = YGNodeNewWithConfig(config);
+  YGNodeStyleSetPositionType(root, YGPositionTypeAbsolute);
+  YGNodeStyleSetWidth(root, 300);
+  YGNodeStyleSetHeight(root, 300);
+
+  YGNodeRef root_child0 = YGNodeNewWithConfig(config);
+  YGNodeStyleSetWidth(root_child0, 50);
+  YGNodeStyleSetAspectRatio(root_child0, 0 / 1);
+  YGNodeInsertChild(root, root_child0, 0);
+  YGNodeCalculateLayout(root, YGUndefined, YGUndefined, YGDirectionLTR);
+
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetLeft(root));
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetTop(root));
+  ASSERT_FLOAT_EQ(300, YGNodeLayoutGetWidth(root));
+  ASSERT_FLOAT_EQ(300, YGNodeLayoutGetHeight(root));
+
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetLeft(root_child0));
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetTop(root_child0));
+  ASSERT_FLOAT_EQ(50, YGNodeLayoutGetWidth(root_child0));
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetHeight(root_child0));
+
+  YGNodeCalculateLayout(root, YGUndefined, YGUndefined, YGDirectionRTL);
+
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetLeft(root));
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetTop(root));
+  ASSERT_FLOAT_EQ(300, YGNodeLayoutGetWidth(root));
+  ASSERT_FLOAT_EQ(300, YGNodeLayoutGetHeight(root));
+
+  ASSERT_FLOAT_EQ(250, YGNodeLayoutGetLeft(root_child0));
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetTop(root_child0));
+  ASSERT_FLOAT_EQ(50, YGNodeLayoutGetWidth(root_child0));
+  ASSERT_FLOAT_EQ(0, YGNodeLayoutGetHeight(root_child0));
+
+  YGNodeFreeRecursive(root);
+
+  YGConfigFree(config);
+}

yoga/style/Style.h

@@ -199,7 +199,11 @@ class YG_EXPORT Style {
     return pool_.getNumber(aspectRatio_);
   }
   void setAspectRatio(FloatOptional value) {
-    pool_.store(aspectRatio_, value);
+    // degenerate aspect ratios act as auto.
+    // see https://drafts.csswg.org/css-sizing-4/#valdef-aspect-ratio-ratio
+    pool_.store(
+        aspectRatio_,
+        value == 0.0f || std::isinf(value.unwrap()) ? FloatOptional{} : value);
   }
 
   bool horizontalInsetsDefined() const {