Animation: Add template for ListStyleInterpolation

Source/core/animation/ListStyleInterpolation.h

Index: Source/core/animation/ListStyleInterpolation.h
diff --git a/Source/core/animation/ListStyleInterpolation.h b/Source/core/animation/ListStyleInterpolation.h
new file mode 100644
index 0000000000000000000000000000000000000000..f5f351254b7a590bbb9bd8dd9a255359fd85d4c3
--- /dev/null
+++ b/Source/core/animation/ListStyleInterpolation.h
@@ -0,0 +1,139 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef ListStyleInterpolation_h
+#define ListStyleInterpolation_h
+
+#include "core/animation/StyleInterpolation.h"
+#include "core/css/CSSPrimitiveValue.h"
+#include "core/css/CSSValueList.h"
+#include "core/css/resolver/StyleBuilder.h"
+
+namespace blink {
+
+template<typename T, typename NI>

[dstockwell, 2015/01/30 04:24:01]

expand T and NI into CamelWords

I have no idea what NI is yet :P

[evemj (not active), 2015/02/02 03:56:02]

Done.

+class ListStyleInterpolationImpl : public StyleInterpolation {
+public:
+    static PassRefPtrWillBeRawPtr<ListStyleInterpolationImpl<T, NI>> create(const CSSValue& start, const CSSValue& end, CSSPropertyID id, InterpolationRange range = RangeAll)
+    {
+        OwnPtrWillBeRawPtr<WillBeHeapVector<typename T::NonInterpolableType>> startNonInterpolableData = adoptPtrWillBeNoop(new WillBeHeapVector<typename T::NonInterpolableType>());
+        OwnPtrWillBeRawPtr<WillBeHeapVector<typename T::NonInterpolableType>> endNonInterpolableData = adoptPtrWillBeNoop(new WillBeHeapVector<typename T::NonInterpolableType>());
+
+        const CSSValueList& startList = toCSSValueList(start);
+        const CSSValueList& endList = toCSSValueList(end);
+
+        for (size_t i = 0; i < toCSSValueList(start).length(); i++) {
+            if (!T::canCreateFrom(*startList.item(i), *endList.item(i))) {
+                return nullptr;
+            }
+        }
+
+        OwnPtrWillBeRawPtr<InterpolableValue> startValue = listToInterpolableValue(start, *startNonInterpolableData.get());
+        OwnPtrWillBeRawPtr<InterpolableValue> endValue = listToInterpolableValue(end, *endNonInterpolableData.get());
+
+        return adoptRefWillBeNoop(new ListStyleInterpolationImpl<T, NI>(startValue.release(), endValue.release(), id, startNonInterpolableData.release(), range));
+    }
+
+    virtual void apply(StyleResolverState& state) const override
+    {
+        StyleBuilder::applyProperty(m_id, state, interpolableValueToList(m_cachedValue.get(), *m_nonInterpolableData.get(), m_range).get());
+    }
+
+private:
+    ListStyleInterpolationImpl(PassOwnPtrWillBeRawPtr<InterpolableValue> start, PassOwnPtrWillBeRawPtr<InterpolableValue> end, CSSPropertyID id,
+        PassOwnPtrWillBeRawPtr<WillBeHeapVector<typename T::NonInterpolableType>> nonInterpolableData, InterpolationRange range = RangeAll)
+        : StyleInterpolation(start, end, id), m_range(range), m_nonInterpolableData(nonInterpolableData)
+    {
+    }
+
+    InterpolationRange m_range;
+
+    OwnPtrWillBeRawPtr<WillBeHeapVector<typename T::NonInterpolableType>> m_nonInterpolableData;

[dstockwell, 2015/01/30 04:24:01]

Why heap vector?

[evemj (not active), 2015/02/02 03:56:02]

Done.

I didn't fully understand how the WillBeHeapVector worked, but Eric explained it
to me so I've changed it to be just be a Vector now

+
+    static PassOwnPtrWillBeRawPtr<InterpolableValue> listToInterpolableValue(const CSSValue& value, WillBeHeapVector<typename T::NonInterpolableType>& nonInterpolableData)
+    {
+        const CSSValueList& listValue = toCSSValueList(value);
+        nonInterpolableData.reserveCapacity(listValue.length());
+        OwnPtrWillBeRawPtr<InterpolableList> result = InterpolableList::create(listValue.length());
+        typename T::NonInterpolableType elementData = false;

[dstockwell, 2015/01/30 04:24:01]

Can't NonInterpolableType be something other than bool?

[samli, 2015/01/30 07:20:30]

Yes. @eve: this shouldn't be here anymore :)

[evemj (not active), 2015/02/02 03:56:02]

Yep sorry that was a mistake!

Done.

+        for (size_t i = 0; i < listValue.length(); i++) {
+            result->set(i, T::toInterpolableValue(*listValue.item(i), elementData));
+            nonInterpolableData.append(elementData);
+        }
+        return result.release();
+    }
+
+    static PassRefPtrWillBeRawPtr<CSSValue> interpolableValueToList(InterpolableValue* value, const WillBeHeapVector<typename T::NonInterpolableType>& nonInterpolableData, InterpolationRange range = RangeAll)
+    {
+        InterpolableList* listValue = toInterpolableList(value);
+        RefPtrWillBeRawPtr<CSSValueList> result = CSSValueList::createCommaSeparated();
+
+        ASSERT(nonInterpolableData.size() != 0);
+
+        for (size_t i = 0; i < listValue->length(); i++)
+            result->append(T::fromInterpolableValue(*(listValue->get(i)), nonInterpolableData[i], range));
+        return result.release();
+    }
+
+    friend class ListStyleInterpolationTest;
+};
+
+template<typename T>
+class ListStyleInterpolationImpl<T, void> : public StyleInterpolation {
+public:
+    static PassRefPtrWillBeRawPtr<ListStyleInterpolationImpl<T, void>> create(const CSSValue& start, const CSSValue& end, CSSPropertyID id, InterpolationRange range = RangeAll)
+    {
+        return adoptRefWillBeNoop(new ListStyleInterpolationImpl<T, void>(listToInterpolableValue(start), listToInterpolableValue(end), id, range));
+    }
+
+private:
+    ListStyleInterpolationImpl(PassOwnPtrWillBeRawPtr<InterpolableValue> start, PassOwnPtrWillBeRawPtr<InterpolableValue> end, CSSPropertyID id, InterpolationRange range = RangeAll)
+        : StyleInterpolation(start, end, id), m_range(range)
+    {
+    }
+
+    InterpolationRange m_range;
+
+    static PassOwnPtrWillBeRawPtr<InterpolableValue> listToInterpolableValue(const CSSValue& value)
+    {
+        const CSSValueList& listValue = toCSSValueList(value);
+        OwnPtrWillBeRawPtr<InterpolableList> result = InterpolableList::create(listValue.length());
+        for (size_t i = 0; i < listValue.length(); i++)
+            result->set(i, T::toInterpolableValue(*listValue.item(i)));
+        return result.release();
+    }
+
+    static PassRefPtrWillBeRawPtr<CSSValue> interpolableValueToList(InterpolableValue* value, InterpolationRange range = RangeAll)
+    {
+        InterpolableList* listValue = toInterpolableList(value);
+        RefPtrWillBeRawPtr<CSSValueList> result = CSSValueList::createCommaSeparated();
+
+        for (size_t i = 0; i < listValue->length(); i++)
+            result->append(T::fromInterpolableValue(*(listValue->get(i)), range));
+        return result.release();
+    }
+
+    virtual void apply(StyleResolverState& state) const override
+    {
+        StyleBuilder::applyProperty(m_id, state, interpolableValueToList(m_cachedValue.get(), m_range).get());
+    }
+
+    friend class ListStyleInterpolationTest;
+
+};
+
+template<typename T>
+class ListStyleInterpolation {
+public:
+    static PassRefPtrWillBeRawPtr<ListStyleInterpolationImpl<T, typename T::NonInterpolableType>>  maybeCreateFromList(const CSSValue& start, const CSSValue& end, CSSPropertyID id, InterpolationRange range = RangeAll)
+    {
+        if (start.isValueList() && end.isValueList() && toCSSValueList(start).length() == toCSSValueList(end).length())

[dstockwell, 2015/01/30 04:24:01]

Don't we need to support lists of different lengths?

[evemj (not active), 2015/02/02 03:56:02]

I think this class is just for simple lists (not repeatable lists) which only
support lists of the same length.

[dstockwell, 2015/02/02 06:10:11]

Will we create a separate template for repeatable lists? Seems like there will
be a lot of overlap.

[evemj (not active), 2015/02/03 00:25:55]

I got the impression that we would extend this template to deal with repeatable
lists/other properties that use simple list style interpolation as needed

+            return ListStyleInterpolationImpl<T, typename T::NonInterpolableType>::create(start, end, id, range);
+        return nullptr;
+    }
+};
+
+} // namespace blink
+
+#endif // ListStyleInterpolation_h