[bindings] Support passing of ScriptState for namedPropertyQuery form of getter.

Source/core/css/CSSStyleDeclaration.cpp

+// Copyright (c) 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.
+
+#include "config.h"
+#include "core/css/CSSStyleDeclaration.h"
+
+#include "core/css/CSSPropertyMetadata.h"
+#include "core/css/parser/CSSParser.h"
+#include "core/frame/UseCounter.h"
+#include "wtf/text/WTFString.h"
+
+using namespace WTF;
+
+namespace blink {
+
+// Check for a CSS prefix.
+// Passed prefix is all lowercase.
+// First character of the prefix within the property name may be upper or lowercase.
+// Other characters in the prefix within the property name must be lowercase.
+// The prefix within the property name must be followed by a capital letter.
+static bool hasCSSPropertyNamePrefix(const String& propertyName, const char* prefix)
+{
+#if ENABLE(ASSERT)
+    ASSERT(*prefix);
+    for (const char* p = prefix; *p; ++p)
+        ASSERT(isASCIILower(*p));
+    ASSERT(propertyName.length());
+#endif
+
+    if (toASCIILower(propertyName[0]) != prefix[0])
+        return false;
+
+    unsigned length = propertyName.length();
+    for (unsigned i = 1; i < length; ++i) {
+        if (!prefix[i])
+            return isASCIIUpper(propertyName[i]);
+        if (propertyName[i] != prefix[i])
+            return false;
+    }
+    return false;
+}
+
+static CSSPropertyID parseCSSPropertyID(v8::Isolate* isolate, const String& propertyName)
+{
+    unsigned length = propertyName.length();
+    if (!length)
+        return CSSPropertyInvalid;
+
+    StringBuilder builder;
+    builder.reserveCapacity(length);
+
+    unsigned i = 0;
+    bool hasSeenDash = false;
+
+    if (hasCSSPropertyNamePrefix(propertyName, "css")) {
+        i += 3;
+        // getComputedStyle(elem).cssX is a non-standard behaviour
+        // Measure this behaviour as CSSXGetComputedStyleQueries.
+        UseCounter::countIfNotPrivateScript(isolate, callingExecutionContext(isolate), UseCounter::CSSXGetComputedStyleQueries);
+    } else if (hasCSSPropertyNamePrefix(propertyName, "webkit")) {
+        builder.append('-');
+    } else if (isASCIIUpper(propertyName[0])) {
+        return CSSPropertyInvalid;
+    }
+
+    bool hasSeenUpper = isASCIIUpper(propertyName[i]);
+
+    builder.append(toASCIILower(propertyName[i++]));
+
+    for (; i < length; ++i) {
+        UChar c = propertyName[i];
+        if (!isASCIIUpper(c)) {
+            if (c == '-')
+                hasSeenDash = true;
+            builder.append(c);
+        } else {
+            hasSeenUpper = true;
+            builder.append('-');
+            builder.append(toASCIILower(c));
+        }
+    }
+
+    // Reject names containing both dashes and upper-case characters, such as "border-rightColor".
+    if (hasSeenDash && hasSeenUpper)
+        return CSSPropertyInvalid;
+
+    String propName = builder.toString();
+    return unresolvedCSSPropertyID(propName);
+}
+
+static CSSPropertyID cssPropertyInfo(const String& propertyName, v8::Isolate* isolate)
+{
+    typedef HashMap<String, CSSPropertyID> CSSPropertyIDMap;
+    DEFINE_STATIC_LOCAL(CSSPropertyIDMap, map, ());
+    CSSPropertyIDMap::iterator iter = map.find(propertyName);
+    if (iter != map.end())
+        return iter->value;
+
+    CSSPropertyID unresolvedProperty = parseCSSPropertyID(isolate, propertyName);
+    map.add(propertyName, unresolvedProperty);
+    ASSERT(!unresolvedProperty || CSSPropertyMetadata::isEnabledProperty(unresolvedProperty));
+    return unresolvedProperty;
+}
+
+void CSSStyleDeclaration::anonymousNamedGetter(ScriptState* scriptState, const AtomicString& name, StringOrFloat& result)
+{
+    // Search the style declaration.
+    CSSPropertyID unresolvedProperty = cssPropertyInfo(name, scriptState->isolate());
+
+    // Do not handle non-property names.
+    if (!unresolvedProperty)
+        return;
+    CSSPropertyID resolvedProperty = resolveCSSPropertyID(unresolvedProperty);
+
+    RefPtrWillBeRawPtr<CSSValue> cssValue = getPropertyCSSValueInternal(resolvedProperty);
+    if (cssValue) {
+        result.setString(cssValue->cssText());

[haraken, 2015/04/29 15:53:46]

The previous code was using v8SetReturnValueStringOrNull, not
v8SetReturnValueString. Does the setString in the new code keep the behavior?

+        return;
+    }
+
+    result.setString(getPropertyValueInternal(resolvedProperty));
+}
+
+bool CSSStyleDeclaration::anonymousNamedSetter(ScriptState* scriptState, const String& name, const String& propertyValue, ExceptionState& exceptionState)
+{
+    CSSPropertyID unresolvedProperty = cssPropertyInfo(name, scriptState->isolate());
+    if (!unresolvedProperty)
+        return false;
+
+    setPropertyInternal(unresolvedProperty, propertyValue, false, exceptionState);

[haraken, 2015/04/29 15:53:45]

Don't we need:

  if (exceptionState.throwIfNeeded())
    return false;

?

[Jens Widell, 2015/04/30 13:14:13]

We do not. It's the outermost layer's job to actually throw; i.e. the generated
code that calls this function.

If necessary, this function could check 'exceptionState.hadException()' to bail
out early, but it's not necessary in this case since the generated code detects
an exception regardless of what this function returns, and since this function
does nothing more after this and thus has no need to bail out early.

+    return true;
+}
+
+bool CSSStyleDeclaration::namedPropertyQuery(ScriptState* scriptState, const AtomicString& name, ExceptionState&)
+{
+    if (!name.length())

[haraken, 2015/04/29 15:53:45]

Did we have this check in the previous code?

+        return false;
+    // NOTE: cssPropertyInfo lookups incur several mallocs.
+    // Successful lookups have the same cost the first time, but are cached.
+    return cssPropertyInfo(name, scriptState->isolate());

[haraken, 2015/04/29 15:53:45]

In the previous code, we're doing v8SetReturnValueInt(info, 0). Does the new
code keep the behavior?

+}
+
+void CSSStyleDeclaration::namedPropertyEnumerator(Vector<String>& names, ExceptionState&)
+{
+    typedef Vector<String, numCSSProperties - 1> PreAllocatedPropertyVector;
+    DEFINE_STATIC_LOCAL(PreAllocatedPropertyVector, propertyNames, ());
+    static unsigned propertyNamesLength = 0;
+
+    if (propertyNames.isEmpty()) {
+        for (int id = firstCSSProperty; id <= lastCSSProperty; ++id) {
+            CSSPropertyID propertyId = static_cast<CSSPropertyID>(id);
+            if (CSSPropertyMetadata::isEnabledProperty(propertyId))
+                propertyNames.append(getJSPropertyName(propertyId));
+        }
+        std::sort(propertyNames.begin(), propertyNames.end(), codePointCompareLessThan);
+        propertyNamesLength = propertyNames.size();
+    }
+
+    for (unsigned i = 0; i < propertyNamesLength; ++i) {
+        String key = propertyNames.at(i);
+        ASSERT(!key.isNull());
+        names.append(key);
+    }
+}
+
+}

[haraken, 2015/04/29 15:53:45]

// namespace blink