[regexp] Set static property attributes as in spec proposal

'[...] accessor properties who have the attributes { [[Enumerable]]:
false, [[Configurable]]: true } [...]'

BUG=v8:5566

Review-Url: https://codereview.chromium.org/2452913002
Cr-Commit-Position: refs/heads/master@{#40609}

src/bootstrapper.cc

@@ -1874,14 +1874,6 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
     {
       // RegExp getters and setters.
 
-      // TODO(jgruber): This should really be DONT_ENUM | DONT_DELETE.
-      // However, that currently breaks layout test expectations. Note that
-      // Firefox sets a couple of these as enumerable.
-      // On the other hand, installing attributes as DONT_ENUM matches the draft
-      // specification at
-      // https://github.com/claudepache/es-regexp-legacy-static-properties.
-      const PropertyAttributes no_enum = DONT_ENUM;
-
       SimpleInstallGetter(regexp_fun,
                           factory->InternalizeUtf8String("[Symbol.species]"),
                           factory->species_symbol(),
@@ -1889,9 +1881,10 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
 
       // Static properties set by a successful match.
 
+      const PropertyAttributes no_enum = DONT_ENUM;
       SimpleInstallGetterSetter(regexp_fun, factory->input_string(),
                                 Builtins::kRegExpInputGetter,
-                                Builtins::kRegExpInputSetter, DONT_DELETE);
+                                Builtins::kRegExpInputSetter, no_enum);
       SimpleInstallGetterSetter(
           regexp_fun, factory->InternalizeUtf8String("$_"),
           Builtins::kRegExpInputGetter, Builtins::kRegExpInputSetter, no_enum);
@@ -1928,11 +1921,10 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
                                 Builtins::kRegExpRightContextGetter,
                                 Builtins::kEmptyFunction, no_enum);
 
-#define INSTALL_CAPTURE_GETTER(i)                                   \
-  SimpleInstallGetterSetter(regexp_fun,                             \
-                            factory->InternalizeUtf8String("$" #i), \
-                            Builtins::kRegExpCapture##i##Getter,    \
-                            Builtins::kEmptyFunction, DONT_DELETE)
+#define INSTALL_CAPTURE_GETTER(i)                         \
+  SimpleInstallGetterSetter(                              \
+      regexp_fun, factory->InternalizeUtf8String("$" #i), \
+      Builtins::kRegExpCapture##i##Getter, Builtins::kEmptyFunction, no_enum)
       INSTALL_CAPTURE_GETTER(1);
       INSTALL_CAPTURE_GETTER(2);
       INSTALL_CAPTURE_GETTER(3);

test/mjsunit/regress/regress-5566.js

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// https://github.com/tc39/proposal-regexp-legacy-features#additional-properties-of-the-regexp-constructor
+
+const props = [ "input", "$_"
+              , "lastMatch", "$&"
+              , "lastParen", "$+"
+              , "leftContext", "$`"
+              , "rightContext", "$'"
+              , "$1", "$2", "$3", "$4", "$5", "$6", "$7", "$8", "$9"
+              ];
+
+for (let i = 0; i < props.length; i++) {
+  const prop = props[i];
+  const desc = Object.getOwnPropertyDescriptor(RegExp, prop);
+  assertTrue(desc.configurable, prop);
+  assertFalse(desc.enumerable, prop);
+  assertTrue(desc.get !== undefined, prop);
+
+  // TODO(jgruber): Although the spec proposal specifies setting setters to
+  // undefined, we are not sure that this change would be web-compatible, and
+  // we are intentionally sticking with the old behavior for now.
+  assertTrue(desc.set !== undefined, prop);
+}