Web Animations CSS: Support animation of stroke-dasharray property

Source/core/animation/AnimatableRepeatable.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 30 matching lines @@
 size_t lowestCommonMultiple(size_t a, size_t b)
 {
     ASSERT(a && b);
     return a / greatestCommonDivisor(a, b) * b;
 }
 
 } // namespace
 
 namespace WebCore {
 
+bool AnimatableRepeatable::interpolateLists(const Vector<RefPtr<AnimatableValue> >& fromValues, const Vector<RefPtr<AnimatableValue> >& toValues, double fraction, Vector<RefPtr<AnimatableValue> >& interpolatedValues)
+{
+    // Interpolation behaviour spec: http://www.w3.org/TR/css3-transitions/#animtype-repeatable-list
+    ASSERT(interpolatedValues.isEmpty());
+    ASSERT(!fromValues.isEmpty() && !toValues.isEmpty());
+    size_t size = lowestCommonMultiple(fromValues.size(), toValues.size());
+    for (size_t i = 0; i < size; ++i) {
+        const AnimatableValue* from = fromValues[i % fromValues.size()].get();
+        const AnimatableValue* to = toValues[i % toValues.size()].get();
+        // Spec: If a pair of values cannot be interpolated, then the lists are not interpolable.
+        if (!from->isSameType(to))
+            return false;
+        interpolatedValues.append(interpolate(from, to, fraction));
+    }
+    return true;
+}
+
 PassRefPtr<AnimatableValue> AnimatableRepeatable::interpolateTo(const AnimatableValue* value, double fraction) const
 {
-    // Interpolation behaviour spec: http://www.w3.org/TR/css3-transitions/#animtype-repeatable-list
-    const Vector<RefPtr<AnimatableValue> >& otherValues = toAnimatableRepeatable(value)->m_values;
-    ASSERT(!m_values.isEmpty() && !otherValues.isEmpty());
-    Vector<RefPtr<AnimatableValue> > interpolatedValues(lowestCommonMultiple(m_values.size(), otherValues.size()));
-    for (size_t i = 0; i < interpolatedValues.size(); ++i) {
-        const AnimatableValue* from = m_values[i % m_values.size()].get();
-        const AnimatableValue* to = otherValues[i % otherValues.size()].get();
-        // Spec: If a pair of values cannot be interpolated, then the lists are not interpolable.
-        if (!from->isSameType(to))
-            return defaultInterpolateTo(this, value, fraction);
-        interpolatedValues[i] = interpolate(from, to, fraction);
-    }
-    return create(interpolatedValues);
+    Vector<RefPtr<AnimatableValue> > interpolatedValues;
+    bool success = interpolateLists(m_values, toAnimatableRepeatable(value)->m_values, fraction, interpolatedValues);
+    return success ? create(interpolatedValues) : defaultInterpolateTo(this, value, fraction);
 }
 
 PassRefPtr<AnimatableValue> AnimatableRepeatable::addWith(const AnimatableValue* value) const
 {
     const Vector<RefPtr<AnimatableValue> >& otherValues = toAnimatableRepeatable(value)->m_values;
     ASSERT(!m_values.isEmpty() && !otherValues.isEmpty());
     Vector<RefPtr<AnimatableValue> > addedValues(lowestCommonMultiple(m_values.size(), otherValues.size()));
     for (size_t i = 0; i < addedValues.size(); ++i) {
         const AnimatableValue* left = m_values[i % m_values.size()].get();
         const AnimatableValue* right = otherValues[i % otherValues.size()].get();
@@ skipping 10 matching lines @@
     if (m_values.size() != otherValues.size())
         return false;
     for (size_t i = 0; i < m_values.size(); ++i) {
         if (!m_values[i]->equals(otherValues[i].get()))
             return false;
     }
     return true;
 }
 
 } // namespace WebCore