Add back the duplicate property checker

test/cctest/test-parsing.cc

Index: test/cctest/test-parsing.cc
diff --git a/test/cctest/test-parsing.cc b/test/cctest/test-parsing.cc
index 31651904e3a2ca7dc42862bba55188d9de89b1e6..57671c0d9e11907e8bbeaec4f8f5fdb3ab087fee 100644
--- a/test/cctest/test-parsing.cc
+++ b/test/cctest/test-parsing.cc
@@ -2486,7 +2486,7 @@ TEST(StrictObjectLiteralChecking) {
     { NULL, NULL }
   };
 
-  // ES6 allows duplicate properties even in strict mode.
+  // These are only errors in strict mode.
   const char* statement_data[] = {
     "foo: 1, foo: 2",
     "\"foo\": 1, \"foo\": 2",
@@ -2499,7 +2499,7 @@ TEST(StrictObjectLiteralChecking) {
   };
 
   RunParserSyncTest(non_strict_context_data, statement_data, kSuccess);
-  RunParserSyncTest(strict_context_data, statement_data, kSuccess);
+  RunParserSyncTest(strict_context_data, statement_data, kError);
 }
 
 
@@ -2511,17 +2511,23 @@ TEST(ErrorsObjectLiteralChecking) {
   };
 
   const char* statement_data[] = {
-    ",",
-    // Wrong number of parameters
-    "get bar(x) {}",
-    "get bar(x, y) {}",
-    "set bar() {}",
-    "set bar(x, y) {}",
-    // Parsing FunctionLiteral for getter or setter fails
-    "get foo( +",
-    "get foo() \"error\"",
-    NULL
-  };
+      ",", "foo: 1, get foo() {}", "foo: 1, set foo(v) {}",
+      "\"foo\": 1, get \"foo\"() {}", "\"foo\": 1, set \"foo\"(v) {}",
+      "1: 1, get 1() {}", "1: 1, set 1() {}",
+      // It's counter-intuitive, but these collide too (even in classic
+      // mode). Note that we can have "foo" and foo as properties in classic
+      // mode,
+      // but we cannot have "foo" and get foo, or foo and get "foo".
+      "foo: 1, get \"foo\"() {}", "foo: 1, set \"foo\"(v) {}",
+      "\"foo\": 1, get foo() {}", "\"foo\": 1, set foo(v) {}",
+      "1: 1, get \"1\"() {}", "1: 1, set \"1\"() {}",
+      "\"1\": 1, get 1() {}"
+      "\"1\": 1, set 1(v) {}"
+      // Wrong number of parameters
+      "get bar(x) {}",
+      "get bar(x, y) {}", "set bar() {}", "set bar(x, y) {}",
+      // Parsing FunctionLiteral for getter or setter fails
+      "get foo( +", "get foo() \"error\"", NULL};
 
   RunParserSyncTest(context_data, statement_data, kError);
 }
@@ -2565,24 +2571,6 @@ TEST(NoErrorsObjectLiteralChecking) {
     "super: 6",
     "eval: 7",
     "arguments: 8",
-    // Duplicate property names are allowed in ES6.
-    "foo: 1, get foo() {}",
-    "foo: 1, set foo(v) {}",
-    "\"foo\": 1, get \"foo\"() {}",
-    "\"foo\": 1, set \"foo\"(v) {}",
-    "1: 1, get 1() {}",
-    "1: 1, set 1(v) {}",
-    // It's counter-intuitive, but these collide too (even in classic
-    // mode). Note that we can have "foo" and foo as properties in classic mode,
-    // but we cannot have "foo" and get foo, or foo and get "foo".
-    "foo: 1, get \"foo\"() {}",
-    "foo: 1, set \"foo\"(v) {}",
-    "\"foo\": 1, get foo() {}",
-    "\"foo\": 1, set foo(v) {}",
-    "1: 1, get \"1\"() {}",
-    "1: 1, set \"1\"(v) {}",
-    "\"1\": 1, get 1() {}",
-    "\"1\": 1, set 1(v) {}",
     NULL
   };