[GeometryInterface] Add setMatrixValue(transfromList) function.

third_party/WebKit/Source/core/dom/DOMMatrix.cpp

 // Copyright 2014 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 "core/dom/DOMMatrix.h"
 
+#include "core/css/CSSIdentifierValue.h"
+#include "core/css/CSSToLengthConversionData.h"
+#include "core/css/parser/CSSParser.h"
+#include "core/css/resolver/TransformBuilder.h"
+#include "core/layout/api/LayoutViewItem.h"
+#include "core/style/ComputedStyle.h"
+
 namespace blink {
 
 DOMMatrix* DOMMatrix::create(ExceptionState& exceptionState) {
   return new DOMMatrix(TransformationMatrix());
 }
 
 DOMMatrix* DOMMatrix::create(DOMMatrixReadOnly* other,
                              ExceptionState& exceptionState) {
   return new DOMMatrix(other->matrix(), other->is2D());
 }
@@ skipping 187 matching lines @@
     setM34(NAN);
     setM41(NAN);
     setM42(NAN);
     setM43(NAN);
     setM44(NAN);
     setIs2D(false);
   }
   return this;
 }
 
+static inline PassRefPtr<ComputedStyle> createInitialStyle() {
+  RefPtr<ComputedStyle> initialStyle = ComputedStyle::create();
+  initialStyle->font().update(nullptr);
+  return initialStyle;
+}
+
+DOMMatrix* DOMMatrix::setMatrixValue(const String& string,
+                                     ExceptionState& exceptionState) {
+  String inputString;
+  if (string.isEmpty()) {
+    inputString = "matrix(1, 0, 0, 1, 0, 0)";

[meade_UTC10, 2016/10/17 03:22:28]

You can use DEFINE_STATIC_LOCAL to avoid allocating this multiple times.

[Hwanseung Lee, 2016/10/18 16:37:53]

Done.

+  } else {
+    inputString = string;
+  }

[meade_UTC10, 2016/10/17 03:22:28]

This can be shortened to just 3 lines.

String inputString = string;
if (string.isEmpty())
  inputString = identityMatrix2D;

[Hwanseung Lee, 2016/10/18 16:37:53]

Done.

+
+  if (const CSSValue* value =
+          CSSParser::parseSingleValue(CSSPropertyTransform, inputString)) {
+    if (value->isIdentifierValue() &&
+        (toCSSIdentifierValue(value))->getValueID() == CSSValueNone) {
+      exceptionState.throwDOMException(SyntaxError,
+                                       "Failed to parse '" + string + "'.");

[meade_UTC10, 2016/10/17 03:22:28]

This shouldn't continue after throwing the exception right? Need to return
nullptr in this if statement.

[Hwanseung Lee, 2016/10/18 16:37:53]

Done.

+    }
+
+    DEFINE_STATIC_REF(ComputedStyle, initialStyle, createInitialStyle());
+
+    if (TransformBuilder::checkHavingRelativeLengthUnit(*value)) {
+      exceptionState.throwDOMException(SyntaxError,
+                                       "relative length unit can't support.");

[meade_UTC10, 2016/10/17 03:22:28]

Nit: Incorrect English grammar. Should be something like "Relative lengths not
supported".

Same comment as above about returning nullptr after throwing the exception.

[Hwanseung Lee, 2016/10/18 16:37:52]

Done.

+    }
+
+    TransformOperations operations;
+    TransformBuilder::createTransformOperations(
+        *value, CSSToLengthConversionData(initialStyle, initialStyle,
+                                          LayoutViewItem(nullptr), 1.0f),
+        operations);
+
+    // Convert transform operations to a TransformationMatrix. This can fail
+    // if a param has a percentage ('%')
+    if (operations.dependsOnBoxSize()) {
+      exceptionState.throwDOMException(SyntaxError,
+                                       "The transformation depends on the box "
+                                       "size, which is not supported.");

[meade_UTC10, 2016/10/17 03:22:28]

Same comment about returning nullptr after throwing an exception.

[Hwanseung Lee, 2016/10/18 16:37:52]

Done.

+    }
+
+    if (operations.has3DOperation())
+      m_is2D = false;
+
+    m_matrix = TransformationMatrix::create();
+    operations.apply(FloatSize(0, 0), *m_matrix);
+
+  } else {  // There is something there but parsing failed.

[meade_UTC10, 2016/10/17 03:22:28]

This structure would be easier to read (exit early on errors and have one less
indentation level) if it was something more like


const CSSValue* value = CSSParser::parseSingleValue(CSSPropertyTransform,
inputString);
if (!value) {
  exceptionState.throwDOMException(SyntaxError, ...);
  return nullptr;
}

if (value->isIdentifierValue(value)) {
  exceptionState.throwDOMException(SyntaxError, ...);
  return nullptr;
}

... etc

[Hwanseung Lee, 2016/10/18 16:37:53]

Done.

+    exceptionState.throwDOMException(SyntaxError,
+                                     "Failed to parse '" + string + "'.");
+  }
+
+  return this;
+}
+
 }  // namespace blink