harmony-scoping: better error messages for let declarations 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 4414 matching lines @@
       "`foo${\n a`",
       "`foo${\r\n a`",
       "`foo${\r a`",
       "`foo${fn(}`",
       "`foo${1 if}`",
       NULL};
   static const ParserFlag always_flags[] = {kAllowHarmonyTemplates};
   RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
                     arraysize(always_flags));
 }
+
+
+TEST(LexicalScopingSloppyMode) {
+  const char* context_data[][2] = {
+      {"", ""},
+      {"function f() {", "}"},
+      {"{", "}"},
+      {NULL, NULL}};
+  const char* bad_data[] = {
+    "let x = 1;",
+    "for(let x = 1;;){}",
+    "for(let x of []){}",
+    "for(let x in []){}",
+    NULL};
+  static const ParserFlag always_flags[] = {kAllowHarmonyScoping};
+  RunParserSyncTest(context_data, bad_data, kError, NULL, 0, always_flags,
+                    arraysize(always_flags));
+
+  const char* good_data[] = {
+    "let = 1;",
+    "for(let = 1;;){}",
+    NULL};
+  RunParserSyncTest(context_data, good_data, kSuccess, NULL, 0, always_flags,
+                    arraysize(always_flags));
+}