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

test/cctest/test-parsing.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 6757 matching lines @@
 
 TEST(LegacyConst) {
   // clang-format off
   const char* context_data[][2] = {
     {"", ""},
     {"{", "}"},
     {NULL, NULL}
   };
 
   const char* data[] = {
-    "const x",
     "const x = 1",
     "for (const x = 1; x < 1; x++) {}",
     "for (const x in {}) {}",
     "for (const x of []) {}",
     NULL
   };
   // clang-format on
 
-  static const ParserFlag always_flags[] = {kNoLegacyConst};
+  {
+    static const ParserFlag always_flags[] = {kNoLegacyConst};

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

It seems a bit weird to run the LegacyConst test with NoLegacyConst, in
particular when it requires removing one (currently valid) legacy const test.
Can you create a separate ConstSloppy test instead?

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

Agreed and done.

+    RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
+                      arraysize(always_flags));
+  }
 
-  RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
+  RunParserSyncTest(context_data, data, kSuccess);
+
+  {
+    static const ParserFlag always_flags[] = {kAllowHarmonySloppy,
+                                              kNoLegacyConst};
+    RunParserSyncTest(context_data, data, kSuccess, NULL, 0, always_flags,
+                      arraysize(always_flags));
+  }
+}
+
+
+TEST(LetSloppy) {
+  // clang-format off
+  const char* context_data[][2] = {
+    {"", ""},
+    {"'use strict';", ""},
+    {"{", "}"},
+    {NULL, NULL}
+  };
+
+  const char* data[] = {
+    "let x",
+    "let x = 1",
+    "for (let x = 1; x < 1; x++) {}",
+    "for (let x in {}) {}",
+    "for (let x of []) {}",
+    NULL
+  };
+  // clang-format on
+
+  static const ParserFlag always_flags[] = {kAllowHarmonySloppy};
+  RunParserSyncTest(context_data, data, kSuccess, NULL, 0, always_flags,
                     arraysize(always_flags));
-  RunParserSyncTest(context_data, data, kSuccess);
 }