Move ParseUnaryExpression into ParserBase and add tests.

src/parser.h

Index: src/parser.h
diff --git a/src/parser.h b/src/parser.h
index 0c9857a2731d97715d17209f2c916445dfa7576a..e7d170d7514baedc4c78ebcf9430a7c4227f1c69 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -456,6 +456,8 @@ class ParserTraits {
   // Returns true if the expression is of type "this.foo".
   static bool IsThisProperty(Expression* expression);
 
+  static bool IsIdentifier(Expression* expression);
+
   static bool IsBoilerplateProperty(ObjectLiteral::Property* property) {
     return ObjectLiteral::IsBoilerplateProperty(property);
   }
@@ -505,6 +507,21 @@ class ParserTraits {
       Expression** x, Expression* y, Token::Value op, int pos,
       AstNodeFactory<AstConstructionVisitor>* factory);
 
+  // Returns true if we can shortcut the unary expression ("not <literal>" or
+  // "+/- <numeric literal>"). In that case, *expression will be changed to the
+  // shortcut.
+  bool ShortcutLiteralUnaryExpression(

[rossberg, 2014/03/19 11:41:46]

Nit: not sure I like the name. This is doing constant folding, so maybe rather
call it FoldUnaryExpression (and say "constant-fold" instead of "shortcut" in
the comment.

+      Expression** expression, Token::Value op, int pos,
+      AstNodeFactory<AstConstructionVisitor>* factory);
+
+  // Returns true if we can desugar '+foo' into 'foo*1' (plus other similar
+  // constructs). This enables the collection of type feedback without any
+  // special stub and the multiplication is removed later in Crankshaft's
+  // canonicalization pass.
+  bool AddUnaryExpressionTypeFeedback(

[rossberg, 2014/03/19 11:41:46]

Similarly here. I'd perhaps call this RewriteUnaryExpression.

In fact, wouldn't it be possible to merge both these helpers into one function
returning the actual expression directly, such that you can simply do

  return BuildUnaryExpression(expression, op, pos, factory())

in ParseUnaryExpression (after checking the DELETE case)?

[marja, 2014/03/19 12:12:43]

Done.

+      Expression** expression, Token::Value op, int pos,
+      AstNodeFactory<AstConstructionVisitor>* factory);
+
   // Reporting errors.
   void ReportMessageAt(Scanner::Location source_location,
                        const char* message,
@@ -568,7 +585,7 @@ class ParserTraits {
       int function_token_position,
       FunctionLiteral::FunctionType type,
       bool* ok);
-  Expression* ParseUnaryExpression(bool* ok);
+  Expression* ParsePostfixExpression(bool* ok);
 
  private:
   Parser* parser_;