Implement handling of arrow functions in the parser

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 857089ea0662ca374051c07ae000c8da59a04a77..76cff1311f70da0d2fc094f6accb1e26f1e3e94c 100644
--- a/test/cctest/test-parsing.cc
+++ b/test/cctest/test-parsing.cc
@@ -155,6 +155,7 @@ TEST(ScanHTMLEndComments) {
     scanner.Initialize(&stream);
     i::PreParser preparser(&scanner, &log, stack_limit);
     preparser.set_allow_lazy(true);
+    preparser.set_allow_arrow_functions(true);
     i::PreParser::PreParseResult result = preparser.PreParseProgram();
     CHECK_EQ(i::PreParser::kPreParseSuccess, result);
     i::ScriptData data(log.ExtractData());
@@ -170,6 +171,7 @@ TEST(ScanHTMLEndComments) {
     scanner.Initialize(&stream);
     i::PreParser preparser(&scanner, &log, stack_limit);
     preparser.set_allow_lazy(true);
+    preparser.set_allow_arrow_functions(true);
     i::PreParser::PreParseResult result = preparser.PreParseProgram();
     // Even in the case of a syntax error, kPreParseSuccess is returned.
     CHECK_EQ(i::PreParser::kPreParseSuccess, result);
@@ -194,6 +196,7 @@ class ScriptResource : public v8::String::ExternalAsciiStringResource {
 
 
 TEST(UsingCachedData) {
+  i::FLAG_harmony_arrow_functions = true;

[marja, 2014/06/26 14:38:14]

I don't think you need to add this to existing tests.

When I said that you should make sure that existing tests run with arrow
functions enabled, I meant the RunParserSync tests.

For them, it should be enough to add this flag to the ParserFlagEnum and
default_flags (like you did).

   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope handles(isolate);
   v8::Local<v8::Context> context = v8::Context::New(isolate);
@@ -241,6 +244,7 @@ TEST(PreparseFunctionDataIsUsed) {
 
   // Make preparsing work for short scripts.
   i::FLAG_min_preparse_length = 0;
+  i::FLAG_harmony_arrow_functions = true;
 
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope handles(isolate);
@@ -250,31 +254,38 @@ TEST(PreparseFunctionDataIsUsed) {
   CcTest::i_isolate()->stack_guard()->SetStackLimit(
       reinterpret_cast<uintptr_t>(&marker) - 128 * 1024);
 
-  const char* good_code =
-      "function this_is_lazy() { var a; } function foo() { return 25; } foo();";
+  const char* good_code[] = {

[marja, 2014/06/26 14:38:14]

I whined about this change before, I'm still whining about it :)

+    "function this_is_lazy() { var a; } function foo() { return 25; } foo();",
+    NULL
+  };
 
   // Insert a syntax error inside the lazy function.
-  const char* bad_code =
-      "function this_is_lazy() { if (   } function foo() { return 25; } foo();";
+  const char* bad_code[] = {
+    "function this_is_lazy() { if (   } function foo() { return 25; } foo();",
+    NULL
+  };
 
-  v8::ScriptCompiler::Source good_source(v8_str(good_code));
-  v8::ScriptCompiler::Compile(isolate, &good_source,
-                              v8::ScriptCompiler::kProduceDataToCache);
+  for (int i = 0; good_code[i]; i++) {
+    v8::ScriptCompiler::Source good_source(v8_str(good_code[i]));
+    v8::ScriptCompiler::Compile(isolate, &good_source,
+                                v8::ScriptCompiler::kProduceDataToCache);
 
-  const v8::ScriptCompiler::CachedData* cached_data =
-      good_source.GetCachedData();
-  CHECK(cached_data->data != NULL);
-  CHECK_GT(cached_data->length, 0);
+    const v8::ScriptCompiler::CachedData* cached_data =
+        good_source.GetCachedData();
+    CHECK(cached_data->data != NULL);
+    CHECK_GT(cached_data->length, 0);
 
-  // Now compile the erroneous code with the good preparse data. If the preparse
-  // data is used, the lazy function is skipped and it should compile fine.
-  v8::ScriptCompiler::Source bad_source(
-      v8_str(bad_code), new v8::ScriptCompiler::CachedData(
-                            cached_data->data, cached_data->length));
-  v8::Local<v8::Value> result =
-      v8::ScriptCompiler::Compile(isolate, &bad_source)->Run();
-  CHECK(result->IsInt32());
-  CHECK_EQ(25, result->Int32Value());
+    // Now compile the erroneous code with the good preparse data. If the
+    // preparse data is used, the lazy function is skipped and it should
+    // compile fine.
+    v8::ScriptCompiler::Source bad_source(
+        v8_str(bad_code[i]), new v8::ScriptCompiler::CachedData(
+                              cached_data->data, cached_data->length));
+    v8::Local<v8::Value> result =
+        v8::ScriptCompiler::Compile(isolate, &bad_source)->Run();
+    CHECK(result->IsInt32());
+    CHECK_EQ(25, result->Int32Value());
+  }
 }
 
 
@@ -291,6 +302,7 @@ TEST(StandAlonePreParser) {
       "function foo(x, y) { return x + y; }",
       "%ArgleBargle(glop);",
       "var x = new new Function('this.x = 42');",
+      "var f = (x, y) => x + y;",
       NULL
   };
 
@@ -307,6 +319,7 @@ TEST(StandAlonePreParser) {
     i::PreParser preparser(&scanner, &log, stack_limit);
     preparser.set_allow_lazy(true);
     preparser.set_allow_natives_syntax(true);
+    preparser.set_allow_arrow_functions(true);
     i::PreParser::PreParseResult result = preparser.PreParseProgram();
     CHECK_EQ(i::PreParser::kPreParseSuccess, result);
     i::ScriptData data(log.ExtractData());
@@ -341,6 +354,7 @@ TEST(StandAlonePreParserNoNatives) {
     // Preparser defaults to disallowing natives syntax.
     i::PreParser preparser(&scanner, &log, stack_limit);
     preparser.set_allow_lazy(true);
+    preparser.set_allow_arrow_functions(true);

[marja, 2014/06/26 14:38:14]

And these shouldn't be needed either. For these tests, we don't run them with
all experimental features anyway, so no need to make an exception for arrow
functions.

     i::PreParser::PreParseResult result = preparser.PreParseProgram();
     CHECK_EQ(i::PreParser::kPreParseSuccess, result);
     i::ScriptData data(log.ExtractData());
@@ -353,6 +367,7 @@ TEST(StandAlonePreParserNoNatives) {
 TEST(PreparsingObjectLiterals) {
   // Regression test for a bug where the symbol stream produced by PreParser
   // didn't match what Parser wanted to consume.
+  i::FLAG_harmony_arrow_functions = true;
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope handles(isolate);
   v8::Local<v8::Context> context = v8::Context::New(isolate);
@@ -411,6 +426,7 @@ TEST(RegressChromium62639) {
   i::PreParser preparser(&scanner, &log,
                          CcTest::i_isolate()->stack_guard()->real_climit());
   preparser.set_allow_lazy(true);
+  preparser.set_allow_arrow_functions(true);
   i::PreParser::PreParseResult result = preparser.PreParseProgram();
   // Even in the case of a syntax error, kPreParseSuccess is returned.
   CHECK_EQ(i::PreParser::kPreParseSuccess, result);
@@ -445,6 +461,7 @@ TEST(Regress928) {
   i::PreParser preparser(&scanner, &log,
                          CcTest::i_isolate()->stack_guard()->real_climit());
   preparser.set_allow_lazy(true);
+  preparser.set_allow_arrow_functions(true);
   i::PreParser::PreParseResult result = preparser.PreParseProgram();
   CHECK_EQ(i::PreParser::kPreParseSuccess, result);
   i::ScriptData data(log.ExtractData());
@@ -492,6 +509,7 @@ TEST(PreParseOverflow) {
 
   i::PreParser preparser(&scanner, &log, stack_limit);
   preparser.set_allow_lazy(true);
+  preparser.set_allow_arrow_functions(true);
   i::PreParser::PreParseResult result = preparser.PreParseProgram();
   CHECK_EQ(i::PreParser::kPreParseStackOverflow, result);
 }
@@ -913,8 +931,6 @@ static int Utf8LengthHelper(const char* s) {
 
 
 TEST(ScopePositions) {
-  v8::internal::FLAG_harmony_scoping = true;

[marja, 2014/06/26 14:38:14]

Why this change?

-
   // Test the parser for correctly setting the start and end positions
   // of a scope. We check the scope positions of exactly one scope
   // nested in the global scope of a program. 'inner source' is the
@@ -969,7 +985,8 @@ TEST(ScopePositions) {
       "    infunction;\n"
       "  }", "\n"
       "  more;", i::FUNCTION_SCOPE, i::SLOPPY },
-    { "  (function fun", "(a,b) { infunction; }", ")();",
+    { "  start;\n"
+      "  (function fun", "(a,b) { infunction; }", ")();",
       i::FUNCTION_SCOPE, i::SLOPPY },
     { "  for ", "(let x = 1 ; x < 10; ++ x) { block; }", " more;",
       i::BLOCK_SCOPE, i::STRICT },
@@ -1124,6 +1141,7 @@ TEST(ScopePositions) {
     i::Parser parser(&info);
     parser.set_allow_lazy(true);
     parser.set_allow_harmony_scoping(true);
+    parser.set_allow_arrow_functions(true);
     info.MarkAsGlobal();
     info.SetStrictMode(source_data[i].strict_mode);
     parser.Parse();
@@ -1180,7 +1198,8 @@ enum ParserFlag {
   kAllowModules,
   kAllowGenerators,
   kAllowForOf,
-  kAllowHarmonyNumericLiterals
+  kAllowHarmonyNumericLiterals,
+  kAllowArrowFunctions
 };
 
 
@@ -1201,6 +1220,7 @@ void SetParserFlags(i::ParserBase<Traits>* parser,
   parser->set_allow_for_of(flags.Contains(kAllowForOf));
   parser->set_allow_harmony_numeric_literals(
       flags.Contains(kAllowHarmonyNumericLiterals));
+  parser->set_allow_arrow_functions(flags.Contains(kAllowArrowFunctions));
 }
 
 
@@ -1403,6 +1423,7 @@ TEST(ParserSync) {
   CcTest::i_isolate()->stack_guard()->SetStackLimit(
       reinterpret_cast<uintptr_t>(&marker) - 128 * 1024);
 
+  static const ParserFlag always_flags[] = { kAllowArrowFunctions };

[marja, 2014/06/26 14:38:14]

Instead of this, you should add the flag to flags1 below, so the test gets run
with and without it.

   static const ParserFlag flags1[] = {
     kAllowLazy, kAllowHarmonyScoping, kAllowModules, kAllowGenerators,
     kAllowForOf
@@ -1426,7 +1447,8 @@ TEST(ParserSync) {
             termination_data[k],
             context_data[i][1]);
         CHECK(length == kProgramSize);
-        TestParserSync(program.start(), flags1, ARRAY_SIZE(flags1));
+        TestParserSync(program.start(), flags1, ARRAY_SIZE(flags1),
+            kSuccessOrError, always_flags, ARRAY_SIZE(always_flags));
       }
     }
   }
@@ -1435,11 +1457,14 @@ TEST(ParserSync) {
   // interaction with the flags above, so test these separately to reduce
   // the combinatorial explosion.
   static const ParserFlag flags2[] = { kAllowHarmonyNumericLiterals };
-  TestParserSync("0o1234", flags2, ARRAY_SIZE(flags2));
-  TestParserSync("0b1011", flags2, ARRAY_SIZE(flags2));
+  TestParserSync("0o1234", flags2, ARRAY_SIZE(flags2),
+      kSuccessOrError, always_flags, ARRAY_SIZE(always_flags));
+  TestParserSync("0b1011", flags2, ARRAY_SIZE(flags2),
+      kSuccessOrError, always_flags, ARRAY_SIZE(always_flags));
 
   static const ParserFlag flags3[] = { kAllowNativesSyntax };
-  TestParserSync("%DebugPrint(123)", flags3, ARRAY_SIZE(flags3));
+  TestParserSync("%DebugPrint(123)", flags3, ARRAY_SIZE(flags3),
+      kSuccessOrError, always_flags, ARRAY_SIZE(always_flags));
 }
 
 
@@ -1447,6 +1472,8 @@ TEST(StrictOctal) {
   // Test that syntax error caused by octal literal is reported correctly as
   // such (issue 2220).
   v8::V8::Initialize();
+  i::FLAG_harmony_arrow_functions = true;
+
   v8::HandleScope scope(CcTest::isolate());
   v8::Context::Scope context_scope(
       v8::Context::New(CcTest::isolate()));
@@ -1483,7 +1510,7 @@ void RunParserSyncTest(const char* context_data[][2],
 
   static const ParserFlag default_flags[] = {
     kAllowLazy, kAllowHarmonyScoping, kAllowModules, kAllowGenerators,
-    kAllowForOf, kAllowNativesSyntax
+    kAllowForOf, kAllowNativesSyntax, kAllowArrowFunctions
   };
   ParserFlag* generated_flags = NULL;
   if (flags == NULL) {
@@ -1560,6 +1587,10 @@ TEST(ErrorsEvalAndArguments) {
     "function foo(arguments) { }",
     "function foo(bar, eval) { }",
     "function foo(bar, arguments) { }",
+    "(eval) => { }",
+    "(arguments) => { }",
+    "(foo, eval) => { }",
+    "(foo, arguments) => { }",
     "eval = 1;",
     "arguments = 1;",
     "var foo = eval = 1;",
@@ -1616,6 +1647,7 @@ TEST(NoErrorsEvalAndArgumentsStrict) {
   const char* context_data[][2] = {
     { "\"use strict\";", "" },
     { "function test_func() { \"use strict\";", "}" },
+    { "() => { \"use strict\"; ", "}" },
     { NULL, NULL }
   };
 
@@ -1631,7 +1663,9 @@ TEST(NoErrorsEvalAndArgumentsStrict) {
     NULL
   };
 
-  RunParserSyncTest(context_data, statement_data, kSuccess);
+  static const ParserFlag always_flags[] = { kAllowArrowFunctions };
+  RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
+                    always_flags, ARRAY_SIZE(always_flags));
 }
 
 
@@ -1643,6 +1677,7 @@ TEST(ErrorsFutureStrictReservedWords) {
   const char* context_data[][2] = {
     { "\"use strict\";", "" },
     { "function test_func() {\"use strict\"; ", "}"},
+    { "() => { \"use strict\"; ", "}" },
     { NULL, NULL }
   };
 
@@ -1653,6 +1688,8 @@ TEST(ErrorsFutureStrictReservedWords) {
     "function interface() { }",
     "function foo(interface) { }",
     "function foo(bar, interface) { }",
+    "(interface) => { }",
+    "(bar, interface) => { }",
     "interface = 1;",
     "var foo = interface = 1;",
     "++interface;",
@@ -1660,6 +1697,7 @@ TEST(ErrorsFutureStrictReservedWords) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;

[marja, 2014/06/26 14:38:13]

Instead of this, you should use always_true_flags...

Otherwise this test takes longer than needed, because it's run with both the
flag and without the flag (via the default_flags permutation thingy) and then
this FLAG just overrides them.

   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -1668,6 +1706,7 @@ TEST(NoErrorsFutureStrictReservedWords) {
   const char* context_data[][2] = {
     { "", "" },
     { "function test_func() {", "}"},
+    { "() => {", "}" },
     { NULL, NULL }
   };
 
@@ -1685,7 +1724,10 @@ TEST(NoErrorsFutureStrictReservedWords) {
     NULL
   };
 
-  RunParserSyncTest(context_data, statement_data, kSuccess);
+  static const ParserFlag always_flags[] = { kAllowArrowFunctions };
+  RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
+                    always_flags, ARRAY_SIZE(always_flags));
+
 }
 
 
@@ -1698,6 +1740,8 @@ TEST(ErrorsReservedWords) {
     { "\"use strict\";", "" },
     { "var eval; function test_func() {", "}"},
     { "var eval; function test_func() {\"use strict\"; ", "}"},
+    { "var eval; () => {", "}" },
+    { "var eval; () => {\"use strict\"; ", "}" },
     { NULL, NULL }
   };
 
@@ -1708,6 +1752,8 @@ TEST(ErrorsReservedWords) {
     "function super() { }",
     "function foo(super) { }",
     "function foo(bar, super) { }",
+    "(super) => { }",
+    "(bar, super) => { }",
     "super = 1;",
     "var foo = super = 1;",
     "++super;",
@@ -1716,6 +1762,7 @@ TEST(ErrorsReservedWords) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;

[marja, 2014/06/26 14:38:14]

Here too... in all places, where you need the flag, you should use
always_true_flags.

   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -1726,6 +1773,7 @@ TEST(NoErrorsYieldSloppy) {
   const char* context_data[][2] = {
     { "", "" },
     { "function is_not_gen() {", "}" },
+    { "() => {", "}" },
     { NULL, NULL }
   };
 
@@ -1743,7 +1791,9 @@ TEST(NoErrorsYieldSloppy) {
     NULL
   };
 
-  RunParserSyncTest(context_data, statement_data, kSuccess);
+  static const ParserFlag always_flags[] = { kAllowArrowFunctions };
+  RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
+                    always_flags, ARRAY_SIZE(always_flags));
 }
 
 
@@ -1771,6 +1821,7 @@ TEST(ErrorsYieldSloppyGenerator) {
 
   // If generators are not allowed, the error will be produced at the '*' token,
   // so this test works both with and without the kAllowGenerators flag.
+  i::FLAG_harmony_arrow_functions = true;

[marja, 2014/06/26 14:38:14]

And this is completely unnecessary; the test should be ran both with and without
arrow functions (and the default_flags permutation takes care of it if you
remove this line).


(And this goes on throughout this file; pls see all occurrences of
i::FLAG_harmony_arrow_functions.)

   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -1780,6 +1831,7 @@ TEST(ErrorsYieldStrict) {
     { "\"use strict\";", "" },
     { "\"use strict\"; function is_not_gen() {", "}" },
     { "function test_func() {\"use strict\"; ", "}"},
+    { "() => {\"use strict\"; ", "}" },
     { NULL, NULL }
   };
 
@@ -1790,6 +1842,8 @@ TEST(ErrorsYieldStrict) {
     "function yield() { }",
     "function foo(yield) { }",
     "function foo(bar, yield) { }",
+    "(yield) => { }",
+    "(bar, yield) => { }",
     "yield = 1;",
     "var foo = yield = 1;",
     "++yield;",
@@ -1797,6 +1851,7 @@ TEST(ErrorsYieldStrict) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -1817,6 +1872,7 @@ TEST(NoErrorsYield) {
   static const ParserFlag always_true_flags[] = {
     kAllowGenerators
   };
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
                     always_true_flags, 1);
 }
@@ -1842,6 +1898,7 @@ TEST(ErrorsNameOfStrictFunction) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -1860,6 +1917,7 @@ TEST(NoErrorsNameOfStrictFunction) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -1870,6 +1928,7 @@ TEST(ErrorsIllegalWordsAsLabelsSloppy) {
   const char* context_data[][2] = {
     { "", ""},
     { "function test_func() {", "}" },
+    { "() => {", "}" },
     { NULL, NULL }
   };
 
@@ -1887,6 +1946,7 @@ TEST(ErrorsIllegalWordsAsLabelsStrict) {
   const char* context_data[][2] = {
     { "\"use strict\";", "" },
     { "function test_func() {\"use strict\"; ", "}"},
+    { "() => {\"use strict\"; ", "}" },
     { NULL, NULL }
   };
 
@@ -1906,8 +1966,10 @@ TEST(NoErrorsIllegalWordsAsLabels) {
   const char* context_data[][2] = {
     { "", ""},
     { "function test_func() {", "}" },
+    { "() => {", "}" },
     { "\"use strict\";", "" },
     { "\"use strict\"; function test_func() {", "}" },
+    { "\"use strict\"; () => {", "}" },
     { NULL, NULL }
   };
 
@@ -1918,7 +1980,9 @@ TEST(NoErrorsIllegalWordsAsLabels) {
     NULL
   };
 
-  RunParserSyncTest(context_data, statement_data, kSuccess);
+  static const ParserFlag always_flags[] = { kAllowArrowFunctions };
+  RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
+                    always_flags, ARRAY_SIZE(always_flags));
 }
 
 
@@ -1927,6 +1991,7 @@ TEST(ErrorsParenthesizedLabels) {
   const char* context_data[][2] = {
     { "", ""},
     { "function test_func() {", "}" },
+    { "() => {", "}" },
     { NULL, NULL }
   };
 
@@ -1951,6 +2016,7 @@ TEST(NoErrorsParenthesizedDirectivePrologue) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -1972,6 +2038,7 @@ TEST(ErrorsNotAnIdentifierName) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -1994,6 +2061,7 @@ TEST(NoErrorsIdentifierNames) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -2002,6 +2070,7 @@ TEST(DontRegressPreParserDataSizes) {
   // These tests make sure that Parser doesn't start producing less "preparse
   // data" (data which the embedder can cache).
   v8::V8::Initialize();
+  i::FLAG_harmony_arrow_functions = true;
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope handles(isolate);
 
@@ -2085,6 +2154,7 @@ TEST(FunctionDeclaresItselfStrict) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, strict_statement_data, kError);
   RunParserSyncTest(context_data, non_strict_statement_data, kSuccess);
 }
@@ -2105,6 +2175,7 @@ TEST(ErrorsTryWithoutCatchOrFinally) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -2122,6 +2193,7 @@ TEST(NoErrorsTryCatchFinally) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -2137,6 +2209,7 @@ TEST(ErrorsRegexpLiteral) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -2154,6 +2227,7 @@ TEST(NoErrorsRegexpLiteral) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -2174,8 +2248,10 @@ TEST(Intrinsics) {
     kAllowNativesSyntax
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
                     always_true_flags, 1);
+  RunParserSyncTest(context_data, statement_data, kSuccessOrError);
 }
 
 
@@ -2214,6 +2290,7 @@ TEST(NoErrorsNewExpression) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -2233,6 +2310,7 @@ TEST(ErrorsNewExpression) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -2261,6 +2339,7 @@ TEST(StrictObjectLiteralChecking) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(non_strict_context_data, statement_data, kSuccess);
   RunParserSyncTest(strict_context_data, statement_data, kError);
 }
@@ -2303,6 +2382,7 @@ TEST(ErrorsObjectLiteralChecking) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kError);
 }
 
@@ -2348,6 +2428,7 @@ TEST(NoErrorsObjectLiteralChecking) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
   RunParserSyncTest(context_data, statement_data, kSuccess);
 }
 
@@ -2372,6 +2453,7 @@ TEST(TooManyArguments) {
   };
 
   // The test is quite slow, so run it with a reduced set of flags.
+  i::FLAG_harmony_arrow_functions = true;
   static const ParserFlag empty_flags[] = {kAllowLazy};
   RunParserSyncTest(context_data, statement_data, kError, empty_flags, 1);
 }
@@ -2420,6 +2502,8 @@ TEST(StrictDelete) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
+
   RunParserSyncTest(strict_context_data, sloppy_statement_data, kError);
   RunParserSyncTest(sloppy_context_data, sloppy_statement_data, kSuccess);
 
@@ -2496,6 +2580,8 @@ TEST(InvalidLeftHandSide) {
     NULL
   };
 
+  i::FLAG_harmony_arrow_functions = true;
+
   RunParserSyncTest(assignment_context_data, good_statement_data, kSuccess);
   RunParserSyncTest(assignment_context_data, bad_statement_data_common, kError);
   RunParserSyncTest(assignment_context_data, bad_statement_data_for_assignment,
@@ -2512,6 +2598,7 @@ TEST(InvalidLeftHandSide) {
 TEST(FuncNameInferrerBasic) {
   // Tests that function names are inferred properly.
   i::FLAG_allow_natives_syntax = true;
+  i::FLAG_harmony_arrow_functions = true;
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope scope(isolate);
   LocalContext env;
@@ -2553,6 +2640,7 @@ TEST(FuncNameInferrerTwoByte) {
   // Tests function name inferring in cases where some parts of the inferred
   // function name are two-byte strings.
   i::FLAG_allow_natives_syntax = true;
+  i::FLAG_harmony_arrow_functions = true;
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope scope(isolate);
   LocalContext env;
@@ -2578,6 +2666,7 @@ TEST(FuncNameInferrerEscaped) {
   // The same as FuncNameInferrerTwoByte, except that we express the two-byte
   // character as a unicode escape.
   i::FLAG_allow_natives_syntax = true;
+  i::FLAG_harmony_arrow_functions = true;
   v8::Isolate* isolate = CcTest::isolate();
   v8::HandleScope scope(isolate);
   LocalContext env;
@@ -2614,3 +2703,168 @@ TEST(RegressionLazyFunctionWithErrorWithArg) {
              "}\n"
              "this_is_lazy();\n");
 }
+
+
+TEST(ErrorsArrowFunctions) {
+  // Tests that parser and preparser generate the same kind of errors
+  // on invalid arrow function syntax.
+  const char* context_data[][2] = {
+    {"", ";"},
+    {"v = ", ";"},
+    {"bar ? (", ") : baz;"},
+    {"bar ? baz : (", ");"},
+    {"bar[", "];"},
+    {"bar, ", ";"},
+    {"", ", bar;"},
+    { NULL, NULL }
+  };
+
+  const char* statement_data[] = {
+    "=> 0",
+    "=>",
+    "() =>",
+    "=> {}",
+    ") => {}",
+    ", => {}",
+    "(,) => {}",
+    "return => {}",
+    "() => {'value': 42}",
+
+    // Check that the early return introduced in ParsePrimaryExpression
+    // does not accept stray closing parentheses.
+    ")",
+    ") => 0",
+    "foo[()]",
+    "()",
+
+    // Parameter lists with extra parens should be recognized as errors.
+    "(()) => 0",
+    "((x)) => 0",
+    "((x, y)) => 0",
+    "(x, (y)) => 0",
+    "((x, y, z)) => 0",
+    "(x, (y, z)) => 0",
+    "((x, y), z) => 0",
+
+    // Parameter lists are always validated as strict, so those are errors.
+    "eval => {}",
+    "arguments => {}",
+    "yield => {}",
+    "interface => {}",
+    "(eval) => {}",
+    "(arguments) => {}",
+    "(yield) => {}",
+    "(interface) => {}",
+    "(eval, bar) => {}",
+    "(bar, eval) => {}",
+    "(bar, arguments) => {}",
+    "(bar, yield) => {}",
+    "(bar, interface) => {}",
+    // TODO(aperez): Detecting duplicates does not work in PreParser.
+    //"(bar, bar) => {}",
+
+    // The parameter list is parsed as an expression, but only
+    // a comma-separated list of identifier is valid.
+    "32 => {}",
+    "(32) => {}",
+    "(a, 32) => {}",
+    "if => {}",
+    "(if) => {}",
+    "(a, if) => {}",
+    "a + b => {}",
+    "(a + b) => {}",
+    "(a + b, c) => {}",
+    "(a, b - c) => {}",
+    "\"a\" => {}",
+    "(\"a\") => {}",
+    "(\"a\", b) => {}",
+    "(a, \"b\") => {}",
+    "-a => {}",
+    "(-a) => {}",
+    "(-a, b) => {}",
+    "(a, -b) => {}",
+    "{} => {}",
+    "({}) => {}",
+    "(a, {}) => {}",
+    "({}, a) => {}",
+    "a++ => {}",
+    "(a++) => {}",
+    "(a++, b) => {}",
+    "(a, b++) => {}",
+    "[] => {}",
+    "([]) => {}",
+    "(a, []) => {}",
+    "([], a) => {}",
+    "(a = b) => {}",
+    "(a = b, c) => {}",
+    "(a, b = c) => {}",
+    "(foo ? bar : baz) => {}",
+    "(a, foo ? bar : baz) => {}",
+    "(foo ? bar : baz, a) => {}",
+
+    NULL
+  };
+
+  RunParserSyncTest(context_data, statement_data, kError);
+}
+
+
+TEST(NoErrorsArrowFunctions) {
+  // Tests that parser and preparser accept valid arrow functions syntax.
+  const char* context_data[][2] = {
+    {"", ";"},
+    // TODO(aperez): Uncomment this when ParseArrowFunctionLiteral()
+    // generates code and returns a non-NULL expression. Currently it
+    // crashes when expression->set_is_parenthesized(true) is called.
+    //{"bar ? (", ") : baz;"},
+    //{"bar ? baz : (", ");"},
+    {"bar, ", ";"},
+    {"", ", bar;"},
+    { NULL, NULL }
+  };
+
+  const char* statement_data[] = {
+    "() => {}",
+    "() => { return 42 }",
+    "x => { return x; }",
+    "(x) => { return x; }",
+    "(x, y) => { return x + y; }",
+    "(x, y, z) => { return x + y + z; }",
+    "(x, y) => { x.a = y; }",
+    "() => 42",
+    "x => x",
+    "x => x * x",
+    "(x) => x",
+    "(x) => x * x",
+    "(x, y) => x + y",
+    "(x, y, z) => x, y, z",
+    "(x, y) => x.a = y",
+    "() => ({'value': 42})",
+    "x => y => x + y",
+    "(x, y) => (u, v) => x*u + y*v",
+    "(x, y) => z => z * (x + y)",
+    "x => (y, z) => z * (x + y)",
+
+    // Those are comma-separated expressions, with arrow functions as items.
+    // They stress the code for validating arrow function parameter lists.
+    "a, b => 0",
+    "a, b, (c, d) => 0",
+    "(a, b, (c, d) => 0)",
+    "(a, b) => 0, (c, d) => 1",
+    "(a, b => {}, a => a + 1)",
+    // TODO(aperez): Uncomment this when ParseArrowFunctionLiteral()
+    // generates code and returns a non-NULL expression. Currently it
+    // crashes when expression->set_is_parenthesized(true) is called.
+    //"((a, b) => {}, (a => a + 1))",
+    //"(a, (a, (b, c) => 0))",
+
+    // Arrow has more precedence, this is the same as: foo ? bar : (baz = {})
+    "foo ? bar : baz => {}",
+
+    NULL
+  };
+
+  static const ParserFlag always_flags[] = { kAllowArrowFunctions };
+  RunParserSyncTest(context_data, statement_data, kSuccess, NULL, 0,
+                    always_flags, ARRAY_SIZE(always_flags));
+}