Bug 1408312 - Part 1: Add ServoCSSParser utility class. r=xidorn

MozReview-Commit-ID: KzM9332hBSx

--HG--
extra : rebase_source : c048323e36bef9dceb3c86d3cc9ee66aa39efb51

layout/style/ServoBindingList.h

@@ -682,6 +682,14 @@ SERVO_BINDING_FUNC(Servo_ReleaseArcStringData, void,
 SERVO_BINDING_FUNC(Servo_CloneArcStringData, mozilla::ServoRawOffsetArc<RustString>,
                    const mozilla::ServoRawOffsetArc<RustString>* string);
 
+// CSS parsing utility functions.
+SERVO_BINDING_FUNC(Servo_IsValidCSSColor, bool, const nsAString* value);
+SERVO_BINDING_FUNC(Servo_ComputeColor, bool,
+                   RawServoStyleSetBorrowedOrNull set,
+                   nscolor current_color,
+                   const nsAString* value,
+                   nscolor* result_color);
+
 // AddRef / Release functions
 #define SERVO_ARC_TYPE(name_, type_)                                \
   SERVO_BINDING_FUNC(Servo_##name_##_AddRef, void, type_##Borrowed) \

layout/style/ServoCSSParser.cpp

@@ -0,0 +1,27 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* CSS parsing utility functions */
+
+#include "ServoCSSParser.h"
+
+using namespace mozilla;
+
+/* static */ bool
+ServoCSSParser::IsValidCSSColor(const nsAString& aValue)
+{
+  return Servo_IsValidCSSColor(&aValue);
+}
+
+/* static */ bool
+ServoCSSParser::ComputeColor(ServoStyleSet* aStyleSet,
+                             nscolor aCurrentColor,
+                             const nsAString& aValue,
+                             nscolor* aResultColor)
+{
+  return Servo_ComputeColor(aStyleSet ? aStyleSet->RawSet() : nullptr,
+                            aCurrentColor, &aValue, aResultColor);
+}

layout/style/ServoCSSParser.h

@@ -0,0 +1,45 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* CSS parsing utility functions */
+
+#ifndef mozilla_ServoCSSParser_h
+#define mozilla_ServoCSSParser_h
+
+#include "mozilla/ServoBindings.h"
+
+namespace mozilla {
+
+class ServoCSSParser
+{
+public:
+  /**
+   * Returns whether the specified string can be parsed as a valid CSS
+   * <color> value.
+   *
+   * This includes Mozilla-specific keywords such as -moz-default-color.
+   */
+  static bool IsValidCSSColor(const nsAString& aValue);
+
+  /**
+   * Computes an nscolor from the given CSS <color> value.
+   *
+   * @param aStyleSet The style set whose nsPresContext will be used to
+   *   compute system colors and other special color values.
+   * @param aCurrentColor The color value that currentcolor should compute to.
+   * @param aValue The CSS <color> value.
+   * @param aResultColor The resulting computed color value.
+   * @return Whether aValue was successfully parsed and aResultColor was set.
+   */
+  static bool ComputeColor(ServoStyleSet* aStyleSet,
+                           nscolor aCurrentColor,
+                           const nsAString& aValue,
+                           nscolor* aResultColor);
+};
+
+} // namespace mozilla
+
+#endif // mozilla_ServoCSSParser_h

layout/style/moz.build

@@ -103,6 +103,7 @@ EXPORTS.mozilla += [
     'ServoBindingList.h',
     'ServoBindings.h',
     'ServoBindingTypes.h',
+    'ServoCSSParser.h',
     'ServoCSSRuleList.h',
     'ServoDeclarationBlock.h',
     'ServoDocumentRule.h',
@@ -249,6 +250,7 @@ UNIFIED_SOURCES += [
     'RuleNodeCacheConditions.cpp',
     'RuleProcessorCache.cpp',
     'ServoBindings.cpp',
+    'ServoCSSParser.cpp',
     'ServoCSSRuleList.cpp',
     'ServoDeclarationBlock.cpp',
     'ServoDocumentRule.cpp',