michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: 
michael@0: /*
michael@0:  * Any copyright is dedicated to the Public Domain.
michael@0:  * http://creativecommons.org/licenses/publicdomain/
michael@0:  */
michael@0: 
michael@0: function isSyntaxError(code) {
michael@0:   try {
michael@0:     eval(code);
michael@0:     return false;
michael@0:   } catch (exception) {
michael@0:     if (SyntaxError.prototype.isPrototypeOf(exception))
michael@0:       return true;
michael@0:     throw exception;
michael@0:   };
michael@0: };
michael@0: 
michael@0: /* 
michael@0:  * Duplicate parameter names must be tolerated (as per ES3), unless
michael@0:  * the parameter list uses destructuring, in which case we claim the
michael@0:  * user has opted in to a modicum of sanity, and we forbid duplicate
michael@0:  * parameter names.
michael@0:  */
michael@0: assertEq(isSyntaxError("function f(x,x){}"),                false);
michael@0: 
michael@0: assertEq(isSyntaxError("function f(x,[x]){})"),             true);
michael@0: assertEq(isSyntaxError("function f(x,{y:x}){})"),           true);
michael@0: assertEq(isSyntaxError("function f(x,{x}){})"),             true);
michael@0: 
michael@0: assertEq(isSyntaxError("function f([x],x){})"),             true);
michael@0: assertEq(isSyntaxError("function f({y:x},x){})"),           true);
michael@0: assertEq(isSyntaxError("function f({x},x){})"),             true);
michael@0: 
michael@0: assertEq(isSyntaxError("function f([x,x]){}"),              true);
michael@0: assertEq(isSyntaxError("function f({x,x}){}"),              true);
michael@0: assertEq(isSyntaxError("function f({y:x,z:x}){}"),          true);
michael@0: 
michael@0: assertEq(isSyntaxError("function f(x,x,[y]){}"),            true);
michael@0: assertEq(isSyntaxError("function f(x,x,{y}){}"),            true);
michael@0: assertEq(isSyntaxError("function f([y],x,x){}"),            true);
michael@0: assertEq(isSyntaxError("function f({y},x,x){}"),            true);
michael@0: 
michael@0: assertEq(isSyntaxError("function f(a,b,c,d,e,f,g,h,b,[y]){}"),  true);
michael@0: assertEq(isSyntaxError("function f([y],a,b,c,d,e,f,g,h,a){}"),  true);
michael@0: assertEq(isSyntaxError("function f([a],b,c,d,e,f,g,h,i,a){}"),  true);
michael@0: assertEq(isSyntaxError("function f(a,b,c,d,e,f,g,h,i,[a]){}"),  true);
michael@0: assertEq(isSyntaxError("function f(a,b,c,d,e,f,g,h,i,[a]){}"),  true);
michael@0: 
michael@0: reportCompare(true, true);