[parser] improve inferred function names for async arrow functions

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 7822 matching lines @@
     "class C {}; class C2 extends C { static async prototype() {} }",
 
     "var f = async() => ((async(x = await 1) => x)();",
 
     "var asyncFn = async function() { function await() {} }",
     "var asyncFn = async() => { function await() {} }",
     "var O = { async method() { function await() {} } }",
     "async function foo() { function await() {} }",
 
     // Henrique Ferreiro's bug (tm)
-    "(async function foo() { } foo => 1)",
-    "(async function foo() { } () => 1)",
-    "(async function foo() { } => 1)",
-    "(async function() { } foo => 1)",
+    "(async function foo1() { } foo2 => 1)",
+    "(async function foo3() { } () => 1)",
+    "(async function foo4() { } => 1)",
+    "(async function() { } foo5 => 1)",
     "(async function() { } () => 1)",
     "(async function() { } => 1)",
-    "(async.foo => 1)",
-    "(async.foo foo => 1)",
-    "(async.foo () => 1)",
-    "(async().foo => 1)",
-    "(async().foo foo => 1)",
-    "(async().foo () => 1)",
-    "(async['foo'] => 1)",
-    "(async['foo'] foo => 1)",
-    "(async['foo'] () => 1)",
-    "(async()['foo'] => 1)",
-    "(async()['foo'] foo => 1)",
-    "(async()['foo'] () => 1)",
-    "(async`foo` => 1)",
-    "(async`foo` foo => 1)",
-    "(async`foo` () => 1)",
-    "(async`foo`.bar => 1)",
-    "(async`foo`.bar foo => 1)",
-    "(async`foo`.bar () => 1)",
+    "(async.foo6 => 1)",
+    "(async.foo7 foo8 => 1)",
+    "(async.foo9 () => 1)",
+    "(async().foo10 => 1)",
+    "(async().foo11 foo12 => 1)",
+    "(async().foo13 () => 1)",
+    "(async['foo14'] => 1)",
+    "(async['foo15'] foo16 => 1)",
+    "(async['foo17'] () => 1)",
+    "(async()['foo18'] => 1)",
+    "(async()['foo19'] foo20 => 1)",
+    "(async()['foo21'] () => 1)",
+    "(async`foo22` => 1)",
+    "(async`foo23` foo24 => 1)",
+    "(async`foo25` () => 1)",
+    "(async`foo26`.bar27 => 1)",
+    "(async`foo28`.bar29 foo30 => 1)",
+    "(async`foo31`.bar32 () => 1)",
 
     // v8:5148 assert that errors are still thrown for calls that may have been
     // async functions
-    "async({ foo = 1 })",
+    "async({ foo33 = 1 })",
     NULL
   };
 
   const char* strict_error_data[] = {
     "var O = { async method(eval) {} }",
     "var O = { async ['meth' + 'od'](eval) {} }",
     "var O = { async 'method'(eval) {} }",
     "var O = { async 0(eval) {} }",
 
     "var O = { async method(arguments) {} }",
@@ skipping 260 matching lines @@
     "(a,);",
     "(a,b,c,);",
     NULL
   };
   // clang-format on
 
   static const ParserFlag always_flags[] = {kAllowHarmonyTrailingCommas};
   RunParserSyncTest(context_data, data, kError, NULL, 0, always_flags,
                     arraysize(always_flags));
 }