Reland "Make 'name' property on functions configurable."

R=rossberg@chromium.org
BUG=v8:3333
LOG=N

Review URL: https://codereview.chromium.org/303463006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21609 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/bootstrapper.cc

@@ -386,45 +386,47 @@ void Genesis::SetFunctionInstanceDescriptor(
   int size = (prototypeMode == DONT_ADD_PROTOTYPE) ? 4 : 5;
   Map::EnsureDescriptorSlack(map, size);
 
-  PropertyAttributes attribs = static_cast<PropertyAttributes>(
-      DONT_ENUM | DONT_DELETE | READ_ONLY);
+  PropertyAttributes ro_attribs =
+      static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE | READ_ONLY);
+  PropertyAttributes roc_attribs =
+      static_cast<PropertyAttributes>(DONT_ENUM | READ_ONLY);
 
   Handle<AccessorInfo> length =
-      Accessors::FunctionLengthInfo(isolate(), attribs);
+      Accessors::FunctionLengthInfo(isolate(), ro_attribs);
   {  // Add length.
     CallbacksDescriptor d(Handle<Name>(Name::cast(length->name())),
-                          length, attribs);
+                          length, ro_attribs);
     map->AppendDescriptor(&d);
   }
   Handle<AccessorInfo> name =
-      Accessors::FunctionNameInfo(isolate(), attribs);
+      Accessors::FunctionNameInfo(isolate(), roc_attribs);
   {  // Add name.
     CallbacksDescriptor d(Handle<Name>(Name::cast(name->name())),
-                          name, attribs);
+                          name, roc_attribs);
     map->AppendDescriptor(&d);
   }
   Handle<AccessorInfo> args =
-      Accessors::FunctionArgumentsInfo(isolate(), attribs);
+      Accessors::FunctionArgumentsInfo(isolate(), ro_attribs);
   {  // Add arguments.
     CallbacksDescriptor d(Handle<Name>(Name::cast(args->name())),
-                          args, attribs);
+                          args, ro_attribs);
     map->AppendDescriptor(&d);
   }
   Handle<AccessorInfo> caller =
-      Accessors::FunctionCallerInfo(isolate(), attribs);
+      Accessors::FunctionCallerInfo(isolate(), ro_attribs);
   {  // Add caller.
     CallbacksDescriptor d(Handle<Name>(Name::cast(caller->name())),
-                          caller, attribs);
+                          caller, ro_attribs);
     map->AppendDescriptor(&d);
   }
   if (prototypeMode != DONT_ADD_PROTOTYPE) {
     if (prototypeMode == ADD_WRITEABLE_PROTOTYPE) {
-      attribs = static_cast<PropertyAttributes>(attribs & ~READ_ONLY);
+      ro_attribs = static_cast<PropertyAttributes>(ro_attribs & ~READ_ONLY);
     }
     Handle<AccessorInfo> prototype =
-        Accessors::FunctionPrototypeInfo(isolate(), attribs);
+        Accessors::FunctionPrototypeInfo(isolate(), ro_attribs);
     CallbacksDescriptor d(Handle<Name>(Name::cast(prototype->name())),
-                          prototype, attribs);
+                          prototype, ro_attribs);
     map->AppendDescriptor(&d);
   }
 }
@@ -533,6 +535,8 @@ void Genesis::SetStrictFunctionInstanceDescriptor(
       static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE);
   PropertyAttributes ro_attribs =
       static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE | READ_ONLY);
+  PropertyAttributes roc_attribs =
+      static_cast<PropertyAttributes>(DONT_ENUM | READ_ONLY);
 
   Handle<AccessorInfo> length =
       Accessors::FunctionLengthInfo(isolate(), ro_attribs);
@@ -542,10 +546,10 @@ void Genesis::SetStrictFunctionInstanceDescriptor(
     map->AppendDescriptor(&d);
   }
   Handle<AccessorInfo> name =
-      Accessors::FunctionNameInfo(isolate(), ro_attribs);
+      Accessors::FunctionNameInfo(isolate(), roc_attribs);
   {  // Add name.
     CallbacksDescriptor d(Handle<Name>(Name::cast(name->name())),
-                          name, ro_attribs);
+                          name, roc_attribs);
     map->AppendDescriptor(&d);
   }
   {  // Add arguments.

test/mjsunit/es7/object-observe.js

@@ -1142,7 +1142,8 @@ var properties = ["a", "1", 1, "length", "setPrototype", "name", "caller"];
 function blacklisted(obj, prop) {
   return (obj instanceof Int32Array && prop == 1) ||
          (obj instanceof Int32Array && prop === "length") ||
-         (obj instanceof ArrayBuffer && prop == 1)
+         (obj instanceof ArrayBuffer && prop == 1) ||
+         (obj instanceof Function && prop === "name")
 }
 
 for (var i in objects) for (var j in properties) {

test/mjsunit/regress/regress-1530.js

@@ -62,8 +62,9 @@ assertSame(new f().foo, 'other');
 assertSame(Object.getPrototypeOf(new f()), z);
 assertSame(Object.getOwnPropertyDescriptor(f, 'prototype').value, z);
 
-// Verify that non-writability of other properties is respected.
-assertThrows("Object.defineProperty(f, 'name', { value: {} })");
+// Verify that non-configurability of other properties is respected, but
+// non-writability is ignored by Object.defineProperty().
+assertDoesNotThrow("Object.defineProperty(f, 'name', { value: {} })");
 assertThrows("Object.defineProperty(f, 'length', { value: {} })");
 assertThrows("Object.defineProperty(f, 'caller', { value: {} })");
 assertThrows("Object.defineProperty(f, 'arguments', { value: {} })");

test/mjsunit/regress/regress-270142.js

@@ -39,7 +39,7 @@ function g(x) {
 
 function checkNameDescriptor(f) {
   var descriptor = Object.getOwnPropertyDescriptor(f, "name");
-  assertFalse(descriptor.configurable);
+  assertTrue(descriptor.configurable);
   assertFalse(descriptor.enumerable);
   assertFalse(descriptor.writable);
 }