[parser] Disallow Expression in for..of statements

test/mjsunit/es6/iteration-syntax.js

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@@ skipping 48 matching lines @@
 StrictSyntaxError("function f() { for (of of) { } }");
 StrictSyntaxError("function f() { for (var of y) { } }");
 StrictSyntaxError("function f() { for (var of of) { } }");
 StrictSyntaxError("function f() { for (let of y) { } }");
 StrictSyntaxError("function f() { for (let of of) { } }");
 
 StrictSyntaxError("function f() { for (x = 3 of y) { } }");
 StrictSyntaxError("function f() { for (var x = 3 of y) { } }");
 StrictSyntaxError("function f() { for (let x = 3 of y) { } }");
 
+StrictSyntaxError("function f() { for (x of y, z) { } }");

[adamk, 2016/01/19 22:21:47]

Rather than adding tests here (which limits you not just to the parser but also
to strict mode), please add a new test case to test/cctest/test-parsing.cc

Take a look at TEST(ConstParsingForInError) for a good starting point.

+StrictSyntaxError("function f() { for (var x of y, z) { } }");
+StrictSyntaxError("function f() { for (let x of y, z) { } }");
 
 // Alack, this appears to be valid.
 function f() { for (of of y) { } }
 function f() { for (let of of y) { } }
 function f() { for (var of of y) { } }
 
 // This too, of course.
 function f() { for (of in y) { } }
 function f() { for (var of in y) { } }
 function f() { for (let of in y) { } }