[strong] Implement static restrictions on direct eval

test/mjsunit/strong/use-strong.js

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --strong-mode
 
 (function UseStrongScoping() {
   assertThrows("'use strong'; 0 == 0", SyntaxError);
   assertThrows("'use strong'; try {} catch(e) { { 0 == 0 } }", SyntaxError);
   assertThrows("function f() { 'use strong'; 0 == 0 }", SyntaxError);
   assertThrows("'use strong'; function f() { 0 == 0 }", SyntaxError);
   assertThrows("'use strong'; function f() { function g() { 0 == 0 } }", SyntaxError);
-  assertThrows("'use strong'; eval('function f() { 0 == 0 }')", SyntaxError);

[arv (Not doing code reviews), 2015/04/13 14:14:06]

Use a closure

[conradw, 2015/04/13 14:36:33]

This test was checking propagation of strong mode into a direct eval, which
doesn't make sense since direct eval shouldn't be allowed in strong mode. Tests
such as the one on line 11 check the other aspects of strong mode exercised
here.

   assertTrue(eval("function f() { 'use strong' } 0 == 0"));
   assertTrue(eval("eval('\\\'use strong\\\''); 0 == 0"));
 })();
 
 (function UseStrongMixed() {
   assertThrows("'use strict'; 'use strong'; 0 == 0", SyntaxError);
   assertThrows("'use strong'; 'use strict'; 0 == 0", SyntaxError);
   assertThrows("'use strong'; 'use strong'; 0 == 0", SyntaxError);
   assertThrows("'use strict'; function f() { 'use strong'; 0 == 0 }", SyntaxError);
   assertThrows("'use strong'; function f() { 'use strict'; 0 == 0 }", SyntaxError);
   assertTrue(eval("'use strict'; function f() { 'use strong' } 0 == 0"));
   assertTrue(eval("var x; function f() { 'use strong' } delete x"));
   assertThrows("'use strict'; var x; function f() { 'use strong' } delete x", SyntaxError);
 })();