Handle direction control in compositor Animations

cc/animation/animation_unittest.cc

Index: cc/animation/animation_unittest.cc
diff --git a/cc/animation/animation_unittest.cc b/cc/animation/animation_unittest.cc
index 8223cee5855d10a69fa91b4155fc5f5cd81a2eec..3be1818b9e7ab5f4e7ffbbf805531c494f19b5ce 100644
--- a/cc/animation/animation_unittest.cc
+++ b/cc/animation/animation_unittest.cc
@@ -49,15 +49,39 @@ TEST(AnimationTest, TrimTimeInfiniteIterations) {
   EXPECT_EQ(0.5, anim->TrimTimeToCurrentIteration(1.5));
 }
 
-TEST(AnimationTest, TrimTimeAlternating) {
+TEST(AnimationTest, TrimTimeReverse) {

[mithro-old, 2014/03/03 06:30:52]

This suggestion is **optional**, it doesn't block landing this patch.

It would be nice to see a simple test which showed TrimTimeReverse/Alternative
interacting with pause time, start time and offset. 

   scoped_ptr<Animation> anim(CreateAnimation(-1));
-  anim->set_alternates_direction(true);
+  anim->set_direction(Animation::Reverse);
+  EXPECT_EQ(1.0, anim->TrimTimeToCurrentIteration(0));
+  EXPECT_EQ(0.75, anim->TrimTimeToCurrentIteration(0.25));
+  EXPECT_EQ(0.5, anim->TrimTimeToCurrentIteration(0.5));
+  EXPECT_EQ(0.25, anim->TrimTimeToCurrentIteration(0.75));
+  EXPECT_EQ(1.0, anim->TrimTimeToCurrentIteration(1.0));
+  EXPECT_EQ(0.75, anim->TrimTimeToCurrentIteration(1.25));
+}
+
+TEST(AnimationTest, TrimTimeAlternate) {
+  scoped_ptr<Animation> anim(CreateAnimation(-1));
+  anim->set_direction(Animation::Alternate);
   EXPECT_EQ(0, anim->TrimTimeToCurrentIteration(0.0));
+  EXPECT_EQ(0.25, anim->TrimTimeToCurrentIteration(0.25));
   EXPECT_EQ(0.5, anim->TrimTimeToCurrentIteration(0.5));
+  EXPECT_EQ(0.75, anim->TrimTimeToCurrentIteration(0.75));
   EXPECT_EQ(1, anim->TrimTimeToCurrentIteration(1.0));
   EXPECT_EQ(0.75, anim->TrimTimeToCurrentIteration(1.25));
 }
 
+TEST(AnimationTest, TrimTimeAlternateReverse) {
+  scoped_ptr<Animation> anim(CreateAnimation(-1));
+  anim->set_direction(Animation::AlternateReverse);
+  EXPECT_EQ(1.0, anim->TrimTimeToCurrentIteration(0.0));
+  EXPECT_EQ(0.75, anim->TrimTimeToCurrentIteration(0.25));
+  EXPECT_EQ(0.5, anim->TrimTimeToCurrentIteration(0.5));
+  EXPECT_EQ(0.25, anim->TrimTimeToCurrentIteration(0.75));
+  EXPECT_EQ(0.0, anim->TrimTimeToCurrentIteration(1.0));
+  EXPECT_EQ(0.25, anim->TrimTimeToCurrentIteration(1.25));
+}
+
 TEST(AnimationTest, TrimTimeStartTime) {
   scoped_ptr<Animation> anim(CreateAnimation(1));
   anim->set_start_time(4);