Allow trailing comma in object literal

Author: alanz

README

@@ -45,6 +45,8 @@ $ cabal install --reinstall alex
 
 Changes
 
+0.2.1 Allow trailing comma in object literal
+
 0.2.0 ECMAScript 3 allows function expressions to have names, AST.JSFunctionExpression now reflects this
 
 0.1.0 Simplified AST by removing JSElement and JSElementList components

language-javascript.cabal

@@ -1,5 +1,5 @@
 Name:                language-javascript
-Version:             0.2.0
+Version:             0.2.1
 Synopsis:            Parser for JavaScript
 Description:         Parses Javascript into an Abstract Syntax Tree (AST).  Initially intended as frontend to hjsmin.
 Homepage:            https://github.com/alanz/language-javascript

runtests.hs

@@ -56,6 +56,8 @@ testSuite = testGroup "Parser"
 
     , testCase "ObjectLiteral4"    (testPE "{evaluate:evaluate,load:function load(s){if(x)return s;1}}" "Right (JSObjectLiteral [JSPropertyNameandValue (JSIdentifier \"evaluate\") [JSIdentifier \"evaluate\"],JSPropertyNameandValue (JSIdentifier \"load\") [JSFunction (JSIdentifier \"load\") [JSIdentifier \"s\"] (JSFunctionBody [JSSourceElements [JSIf (JSExpression [JSIdentifier \"x\"]) (JSReturn [JSExpression [JSIdentifier \"s\"],JSLiteral \";\"]),JSExpression [JSDecimal \"1\"]]])]])")
 
+    , testCase "ObjectLiteral5"    (testPE "{x:1,}"    "Right (JSObjectLiteral [JSPropertyNameandValue (JSIdentifier \"x\") [JSDecimal \"1\"],JSLiteral \",\"])")
+    
     , testCase "ExpressionParen"   (testPE "(56)"     "Right (JSExpressionParen (JSExpression [JSDecimal \"56\"]))")
 
     , testCase "Statement1"        (testStmt "x"        "Right (JSExpression [JSIdentifier \"x\"])")

src/Language/JavaScript/Parser/Grammar.y

@@ -237,13 +237,16 @@ ObjectLiteral : '{' PropertyNameandValueList '}' { AST.JSObjectLiteral $2 }
 --                                  | <Property Name and Value List> ',' <Property Name> ':' <Assignment Expression>
 
 -- Seems we can have function declarations in the value part too                           
+-- TODO: And can end with a comma
 PropertyNameandValueList :: { [ AST.JSNode ] }
 PropertyNameandValueList : PropertyName ':' AssignmentExpression { [(AST.JSPropertyNameandValue $1 $3)] }
                          | PropertyName ':' FunctionDeclaration { [(AST.JSPropertyNameandValue $1 [$3])] }
                          | PropertyNameandValueList ',' PropertyName ':' AssignmentExpression 
                            { ($1 ++ [(AST.JSPropertyNameandValue $3 $5)])  } 
                          | PropertyNameandValueList ',' PropertyName ':' FunctionDeclaration 
                            { ($1 ++ [(AST.JSPropertyNameandValue $3 [$5])])  } 
+                         | PropertyNameandValueList ',' 
+                           { ($1 ++ [(AST.JSLiteral ",")])  } 
                          |    { [] }