Web Animations CSS: Assert underlying value is not used

Source/core/animation/KeyframeAnimationEffectTest.cpp

Index: Source/core/animation/KeyframeAnimationEffectTest.cpp
diff --git a/Source/core/animation/KeyframeAnimationEffectTest.cpp b/Source/core/animation/KeyframeAnimationEffectTest.cpp
index 9975981cddd3a54ab0cd02c51b5051df2b163f4d..07f1a5e734b8b3a7158d46da48116dce25a89433 100644
--- a/Source/core/animation/KeyframeAnimationEffectTest.cpp
+++ b/Source/core/animation/KeyframeAnimationEffectTest.cpp
@@ -341,4 +341,26 @@ TEST(KeyframeAnimationEffect, MultipleIterations)
     expectDoubleValue(2.0, effect->sample(2, 0.5)->begin()->value->compositeOnto(unknownAnimatableValue(0.0)));
 }
 
+TEST(KeyframeAnimationEffect, DependsOnUnderlyingValue)
+{
+    KeyframeAnimationEffect::KeyframeVector keyframes(3);
+    keyframes[0] = Keyframe::create();
+    keyframes[0]->setOffset(0.0);
+    keyframes[0]->setPropertyValue(CSSPropertyLeft, pixelAnimatableValue(1.0));
+    keyframes[0]->setComposite(AnimationEffect::CompositeAdd);
+    keyframes[1] = Keyframe::create();
+    keyframes[1]->setOffset(0.5);
+    keyframes[1]->setPropertyValue(CSSPropertyLeft, pixelAnimatableValue(1.0));
+    keyframes[2] = Keyframe::create();
+    keyframes[2]->setOffset(1.0);
+    keyframes[2]->setPropertyValue(CSSPropertyLeft, pixelAnimatableValue(1.0));
+
+    RefPtr<KeyframeAnimationEffect> effect = KeyframeAnimationEffect::create(keyframes);
+    EXPECT_TRUE(effect->sample(0, 0)->begin()->value->dependsOnUnderlyingValue());
+    EXPECT_TRUE(effect->sample(0, 0.25)->begin()->value->dependsOnUnderlyingValue());

[Steve Block, 2013/08/09 04:32:31]

Testing at 0.25 is a little confusing - it implies there's something special
about the half-way point. We expect the value to be true all the way up to
0.499999, right?

[alancutter (OOO until 2018), 2013/08/09 05:46:31]

Added more stops to test.

+    EXPECT_FALSE(effect->sample(0, 0.5)->begin()->value->dependsOnUnderlyingValue());
+    EXPECT_FALSE(effect->sample(0, 0.75)->begin()->value->dependsOnUnderlyingValue());
+    EXPECT_FALSE(effect->sample(0, 1)->begin()->value->dependsOnUnderlyingValue());
+}
+
 } // namespace