[es6] Initial support for let/const bindings in sloppy mode

test/mjsunit/harmony/block-let-semantics-sloppy.js

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-"use strict";
+// Flags: --harmony-sloppy --no-legacy-const
 
 // Test temporal dead zone semantics of let bound variables in
 // function and block scopes.
 
 function TestFunctionLocal(s) {
   try {
     eval("(function(){" + s + "; })")();
   } catch (e) {
     assertInstanceof(e, ReferenceError);
     return;
@@ skipping 49 matching lines @@
 // Use before initialization with a dynamic lookup.
 TestAll('eval("x + 1;"); let x;');
 TestAll('eval("x = 1;"); let x;');
 TestAll('eval("x += 1;"); let x;');
 TestAll('eval("++x;"); let x;');
 TestAll('eval("x++;"); let x;');
 TestAll('eval("x"); const x = 1;');
 
 // Use before initialization with check for eval-shadowed bindings.
 TestAll('function f() { eval("var y = 2;"); x + 1; }; f(); let x;');
-TestAll('function f() { eval("var y = 2;"); x = 1; }; f(); let x;');
+// TestAll('function f() { eval("var y = 2;"); x = 1; }; f(); let x;');

[rossberg, 2015/07/08 11:49:56]

Can you add a TODO explaining why this is commented out right now? And file a
bug, too, so it doesn't get lost.

[arv (Not doing code reviews), 2015/07/08 13:43:45]

Done.

 TestAll('function f() { eval("var y = 2;"); x += 1; }; f(); let x;');
 TestAll('function f() { eval("var y = 2;"); ++x; }; f(); let x;');
 TestAll('function f() { eval("var y = 2;"); x++; }; f(); let x;');
 
 // Test that variables introduced by function declarations are created and
 // initialized upon entering a function / block scope.
 function f() {
   {
     assertEquals(2, g1());
     assertEquals(2, eval("g1()"));
@@ skipping 69 matching lines @@
     }
     eval("1 + 1");
     return x + inner();
   }
 
   let x = 1;
   return middle();
 }
 
 assertEquals(2, outer());