Alternative syntax for element.animate list of keyframes

third_party/WebKit/Source/core/animation/EffectInput.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 29 matching lines @@
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/NodeComputedStyle.h"
 #include "wtf/ASCIICType.h"
 #include "wtf/HashSet.h"
 #include "wtf/NonCopyingSort.h"
 
 namespace blink {
 
+namespace {
+bool compareKeyframes(const RefPtr<StringKeyframe>& a, const RefPtr<StringKeyframe>& b)
+{
+    return (a->offset() < b->offset());

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

No need for the outer brackets.

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:35]

Done.

+}
+} // namespace

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

Blank lines around the namespace boundaries.

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:36]

Done.

+
+EffectModel* EffectInput::convert(Element* element, const EffectModelOrDictionarySequenceOrDictionary& effectInput, ExceptionState& exceptionState)
+{
+    if (effectInput.isEffectModel())
+        return effectInput.getAsEffectModel();
+    if (effectInput.isDictionarySequence())
+        return convert(element, effectInput.getAsDictionarySequence(), exceptionState);
+    if (effectInput.isDictionary()) {
+        return convert(element, effectInput.getAsDictionary(), exceptionState);
+    }
+    return nullptr;
+}
+
+bool EffectInput::setKeyframeValue(Element* element, StringKeyframe* keyframe, const String& property, const String& value)

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

Blink style dictates the element and keyframe parameters should be a mutable
references.

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:35]

I'm happy to make the keyframe parameter a StringKeyframe&, but the Element*
parameter is an existing parameter from before I touched this file. Should all
the Element* parameters be changed (in which case all the call sites of these
functions will need to be updated) or is this an acceptable exception?

[alancutter (OOO until 2018), 2016/02/25 06:52:27]

If a function dereferences it without performing a null check then it ought to
be a reference, this is the case for setKeyframeValue() and
createEffectModelFromKeyframes().

[suzyh_UTC10 (ex-contributor), 2016/02/26 04:35:30]

Done.

+{
+    StyleSheetContents* styleSheetContents = element->document().elementSheet().contents();
+    CSSPropertyID cssProperty = AnimationInputHelpers::keyframeAttributeToCSSProperty(property, element->document());
+    if (cssProperty != CSSPropertyInvalid) {
+        keyframe->setCSSPropertyValue(cssProperty, value, element, styleSheetContents);
+        return CompositorAnimations::isCompositableProperty(cssProperty);
+    }
+    cssProperty = AnimationInputHelpers::keyframeAttributeToPresentationAttribute(property, *element);
+    if (cssProperty != CSSPropertyInvalid) {
+        keyframe->setPresentationAttributeValue(cssProperty, value, element, styleSheetContents);
+        return false;
+    }
+    const QualifiedName* svgAttribute = AnimationInputHelpers::keyframeAttributeToSVGAttribute(property, *element);
+    if (svgAttribute)
+        keyframe->setSVGAttributeValue(*svgAttribute, value);
+    return false;
+}
+
+// TODO(alancutter): Remove this once composited animations no longer depend on AnimatableValues.
+void EffectInput::updateElementStyleIfNeeded(Element* element, bool encounteredCompositableProperty)
+{
+    if (encounteredCompositableProperty && element->inActiveDocument())
+        element->document().updateLayoutTreeForNodeIfNeeded(element);

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

This code always needs to be run before the call to
forceConversionsToAnimatableValues() in createEffectModelFromKeyframes() so it
should just be inlined there in that function.

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:35]

Done.

+}
+
+EffectModel* EffectInput::createEffectModelFromKeyframes(Element* element, const StringKeyframeVector& keyframes, ExceptionState& exceptionState)

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

element should be a reference.

+{
+    StringKeyframeEffectModel* keyframeEffectModel = StringKeyframeEffectModel::create(keyframes);
+    if (!RuntimeEnabledFeatures::cssAdditiveAnimationsEnabled()) {
+        for (const auto& keyframeGroup : keyframeEffectModel->getPropertySpecificKeyframeGroups()) {
+            PropertyHandle property = keyframeGroup.key;
+            if (!property.isCSSProperty())
+                continue;
+
+            for (const auto& keyframe : keyframeGroup.value->keyframes()) {
+                if (keyframe->isNeutral()) {
+                    exceptionState.throwDOMException(NotSupportedError, "Partial keyframes are not supported.");
+                    return nullptr;
+                }
+                if (keyframe->composite() != EffectModel::CompositeReplace) {
+                    exceptionState.throwDOMException(NotSupportedError, "Additive animations are not supported.");
+                    return nullptr;
+                }
+            }
+        }
+    }
+    keyframeEffectModel->forceConversionsToAnimatableValues(*element, element->computedStyle());
+
+    return keyframeEffectModel;
+}
+
 EffectModel* EffectInput::convert(Element* element, const Vector<Dictionary>& keyframeDictionaryVector, ExceptionState& exceptionState)
 {
     if (!element)
         return nullptr;
 
-    StyleSheetContents* styleSheetContents = element->document().elementSheet().contents();
     StringKeyframeVector keyframes;
     double lastOffset = 0;
     bool encounteredCompositableProperty = false;
 
     for (const auto& keyframeDictionary : keyframeDictionaryVector) {
         RefPtr<StringKeyframe> keyframe = StringKeyframe::create();
 
         ScriptValue scriptValue;
         bool frameHasOffset = DictionaryHelper::get(keyframeDictionary, "offset", scriptValue) && !scriptValue.isNull();
 
@@ skipping 13 matching lines @@
 
             if (offset < lastOffset) {
                 exceptionState.throwDOMException(InvalidModificationError, "Keyframes with specified offsets are not sorted");
                 return nullptr;
             }
 
             lastOffset = offset;
 
             keyframe->setOffset(offset);
         }
-        keyframes.append(keyframe);
 
         String compositeString;
         DictionaryHelper::get(keyframeDictionary, "composite", compositeString);
         if (compositeString == "add")
             keyframe->setComposite(EffectModel::CompositeAdd);
         // TODO(alancutter): Support "accumulate" keyframe composition.
 
         String timingFunctionString;
         if (DictionaryHelper::get(keyframeDictionary, "easing", timingFunctionString)) {
             if (RefPtr<TimingFunction> timingFunction = AnimationInputHelpers::parseTimingFunction(timingFunctionString))
                 keyframe->setEasing(timingFunction);
         }
 
         Vector<String> keyframeProperties;
         keyframeDictionary.getPropertyNames(keyframeProperties);
         for (const auto& property : keyframeProperties) {
-            String value;
-            DictionaryHelper::get(keyframeDictionary, property, value);
-
-            CSSPropertyID cssProperty = AnimationInputHelpers::keyframeAttributeToCSSProperty(property, element->document());
-            if (cssProperty != CSSPropertyInvalid) {
-                if (!encounteredCompositableProperty && CompositorAnimations::isCompositableProperty(cssProperty))
-                    encounteredCompositableProperty = true;
-
-                keyframe->setCSSPropertyValue(cssProperty, value, element, styleSheetContents);
-                continue;
-            }
-
             if (property == "offset"
                 || property == "composite"
                 || property == "easing") {
                 continue;
             }
 
-            cssProperty = AnimationInputHelpers::keyframeAttributeToPresentationAttribute(property, *element);
-            if (cssProperty != CSSPropertyInvalid) {
-                keyframe->setPresentationAttributeValue(cssProperty, value, element, styleSheetContents);
-                continue;
+            Vector<String> values;
+            bool isList = DictionaryHelper::get(keyframeDictionary, property, values);
+            if (isList)

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

No need for single use bool variable.

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:36]

Done. I used this here to be consistent with the case lower down, although I
guess it is clearer not to use it here. For the case below, I think the code is
clearer with the explicit bool, even if it is single-use. What do you think?

[alancutter (OOO until 2018), 2016/02/25 06:52:27]

True, the name does add to code clarity. Feel free to retain it though
personally I think the error message in the body is enough indication.

+                exceptionState.throwDOMException(InvalidModificationError, "Lists of values not permitted in array-form list of keyframes");

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

Is there a test for this exception?
Shouldn't we return nullptr here?

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:36]

Test: Done.

Return nullptr: Whoops, yes. Fixed.

+
+            String value;
+            DictionaryHelper::get(keyframeDictionary, property, value);

[alancutter (OOO until 2018), 2016/02/24 08:50:02]

Can this return false if the user provides their own toString() method?
Example: element.animate({color: {toString() {}}})
If so we should probably throw a TypeError and have a test case or if not add an
ASSERT.

[suzyh_UTC10 (ex-contributor), 2016/02/25 02:42:35]

Hm, I have no idea. The existing code used DictionaryHelper::get without
checking its return value. Can you file a bug to look into this later?

+
+            encounteredCompositableProperty |= setKeyframeValue(element, keyframe.get(), property, value);
+        }
+        keyframes.append(keyframe);
+    }
+
+    updateElementStyleIfNeeded(element, encounteredCompositableProperty);
+
+    return createEffectModelFromKeyframes(element, keyframes, exceptionState);
+}
+
+EffectModel* EffectInput::convert(Element* element, const Dictionary& keyframeDictionary, ExceptionState& exceptionState)
+{
+    if (!element)
+        return nullptr;
+
+    StringKeyframeVector keyframes;
+    bool encounteredCompositableProperty = false;
+
+    String timingFunctionString;
+    RefPtr<TimingFunction> timingFunction = nullptr;
+    if (DictionaryHelper::get(keyframeDictionary, "easing", timingFunctionString))
+        timingFunction = AnimationInputHelpers::parseTimingFunction(timingFunctionString);
+
+    Vector<String> keyframeProperties;
+    keyframeDictionary.getPropertyNames(keyframeProperties);
+    for (const auto& property : keyframeProperties) {
+        if (property == "offset")
+            exceptionState.throwDOMException(InvalidModificationError, "Keyframe offsets not permitted in object-form list of keyframes");
+        if (property == "composite")
+            exceptionState.throwDOMException(InvalidModificationError, "Keyframe-specific composite operations not permitted in object-form list of keyframes");
+
+        if (property == "easing") {
+            continue;
+        }
+
+        Vector<String> values;
+        bool isList = DictionaryHelper::get(keyframeDictionary, property, values);
+        if (!isList) {
+            String value;
+            DictionaryHelper::get(keyframeDictionary, property, value);
+            values.append(value);
+        }
+
+        size_t numKeyframes = values.size();
+
+        Vector<double> offsets;
+        if (numKeyframes == 1) {
+            offsets.append(1.0);
+        } else {
+            for (size_t i = 0; i < numKeyframes; ++i) {
+                offsets.append(i / (numKeyframes - 1.0));
             }
+        }
 
-            const QualifiedName* svgAttribute = AnimationInputHelpers::keyframeAttributeToSVGAttribute(property, *element);
-            if (svgAttribute)
-                keyframe->setSVGAttributeValue(*svgAttribute, value);
+        for (size_t i = 0; i < numKeyframes; ++i) {
+            RefPtr<StringKeyframe> keyframe = StringKeyframe::create();
+            keyframe->setOffset(offsets[i]);
+
+            const String& value = values[i];
+
+            if (timingFunction)
+                keyframe->setEasing(timingFunction);
+
+            encounteredCompositableProperty |= setKeyframeValue(element, keyframe.get(), property, value);
+            keyframes.append(keyframe);
         }
     }
 
-    // TODO(alancutter): Remove this once composited animations no longer depend on AnimatableValues.
-    if (encounteredCompositableProperty && element->inActiveDocument())
-        element->document().updateLayoutTreeForNodeIfNeeded(element);
+    std::sort(keyframes.begin(), keyframes.end(), compareKeyframes);
 
-    StringKeyframeEffectModel* keyframeEffectModel = StringKeyframeEffectModel::create(keyframes);
-    if (!RuntimeEnabledFeatures::cssAdditiveAnimationsEnabled()) {
-        for (const auto& keyframeGroup : keyframeEffectModel->getPropertySpecificKeyframeGroups()) {
-            PropertyHandle property = keyframeGroup.key;
-            if (!property.isCSSProperty())
-                continue;
+    updateElementStyleIfNeeded(element, encounteredCompositableProperty);
 
-            for (const auto& keyframe : keyframeGroup.value->keyframes()) {
-                if (keyframe->isNeutral()) {
-                    exceptionState.throwDOMException(NotSupportedError, "Partial keyframes are not supported.");
-                    return nullptr;
-                }
-                if (keyframe->composite() != EffectModel::CompositeReplace) {
-                    exceptionState.throwDOMException(NotSupportedError, "Additive animations are not supported.");
-                    return nullptr;
-                }
-            }
-        }
-    }
-    keyframeEffectModel->forceConversionsToAnimatableValues(*element, element->computedStyle());
-
-    return keyframeEffectModel;
-}
-
-EffectModel* EffectInput::convert(Element* element, const EffectModelOrDictionarySequenceOrDictionary& effectInput, ExceptionState& exceptionState)
-{
-    if (effectInput.isEffectModel())
-        return effectInput.getAsEffectModel();
-    if (effectInput.isDictionarySequence())
-        return convert(element, effectInput.getAsDictionarySequence(), exceptionState);
-    if (effectInput.isDictionary()) {
-        Vector<Dictionary> keyframes;
-        keyframes.append(effectInput.getAsDictionary());
-        return convert(element, keyframes, exceptionState);
-    }
-    return nullptr;
+    return createEffectModelFromKeyframes(element, keyframes, exceptionState);
 }
 
 } // namespace blink