ladybird/Userland/Libraries/LibJS/Runtime/Realm.cpp
Linus Groh 040e3abb1d LibJS: Implement SetDefaultGlobalBindings as a standalone function
Instead of hardcoding all the property definitions in GlobalObject's
initialize() function, make it the standalone AO it is supposed to be
that can then be used by other global objects that don't inherit from
JS::GlobalObject.
2022-08-28 19:34:10 +01:00

123 lines
4.4 KiB
C++

/*
* Copyright (c) 2021-2022, Linus Groh <linusg@serenityos.org>
* Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/TypeCasts.h>
#include <LibJS/Heap/DeferGC.h>
#include <LibJS/Runtime/GlobalEnvironment.h>
#include <LibJS/Runtime/GlobalObject.h>
#include <LibJS/Runtime/Realm.h>
#include <LibJS/Runtime/VM.h>
namespace JS {
// 9.3.1 CreateRealm ( ), https://tc39.es/ecma262/#sec-createrealm
Realm* Realm::create(VM& vm)
{
// 1. Let realmRec be a new Realm Record.
auto* realm = vm.heap().allocate_without_realm<Realm>();
// 2. Perform CreateIntrinsics(realmRec).
Intrinsics::create(*realm);
// 3. Set realmRec.[[GlobalObject]] to undefined.
// 4. Set realmRec.[[GlobalEnv]] to undefined.
// 5. Set realmRec.[[TemplateMap]] to a new empty List.
// 6. Return realmRec.
return realm;
}
// 9.6 InitializeHostDefinedRealm ( ), https://tc39.es/ecma262/#sec-initializehostdefinedrealm
ThrowCompletionOr<NonnullOwnPtr<ExecutionContext>> Realm::initialize_host_defined_realm(VM& vm, Function<Object*(Realm&)> create_global_object, Function<Object*(Realm&)> create_global_this_value)
{
DeferGC defer_gc(vm.heap());
// 1. Let realm be CreateRealm().
auto* realm = Realm::create(vm);
// 2. Let newContext be a new execution context.
auto new_context = make<ExecutionContext>(vm.heap());
// 3. Set the Function of newContext to null.
new_context->function = nullptr;
// 4. Set the Realm of newContext to realm.
new_context->realm = realm;
// 5. Set the ScriptOrModule of newContext to null.
new_context->script_or_module = {};
// 6. Push newContext onto the execution context stack; newContext is now the running execution context.
vm.push_execution_context(*new_context);
// 7. If the host requires use of an exotic object to serve as realm's global object,
// let global be such an object created in a host-defined manner.
// Otherwise, let global be undefined, indicating that an ordinary object should be created as the global object.
Object* global = nullptr;
if (create_global_object)
global = create_global_object(*realm);
// 8. If the host requires that the this binding in realm's global scope return an object other than the global object,
// let thisValue be such an object created in a host-defined manner.
// Otherwise, let thisValue be undefined, indicating that realm's global this binding should be the global object.
Object* this_value = nullptr;
if (create_global_this_value)
this_value = create_global_this_value(*realm);
// 9. Perform SetRealmGlobalObject(realm, global, thisValue).
realm->set_global_object(global, this_value);
// 10. Let globalObj be ? SetDefaultGlobalBindings(realm).
auto& global_object = set_default_global_bindings(*realm);
// 11. Create any host-defined global object properties on globalObj.
global_object.initialize(*realm);
// 12. Return unused.
return new_context;
}
// 9.3.3 SetRealmGlobalObject ( realmRec, globalObj, thisValue ), https://tc39.es/ecma262/#sec-setrealmglobalobject
void Realm::set_global_object(Object* global_object, Object* this_value)
{
// 1. If globalObj is undefined, then
if (global_object == nullptr) {
// a. Let intrinsics be realmRec.[[Intrinsics]].
// b. Set globalObj to OrdinaryObjectCreate(intrinsics.[[%Object.prototype%]]).
// NOTE: We allocate a proper GlobalObject directly as this plain object is
// turned into one via SetDefaultGlobalBindings in the spec.
global_object = heap().allocate_without_realm<GlobalObject>(*this);
}
// 2. Assert: Type(globalObj) is Object.
VERIFY(global_object);
// 3. If thisValue is undefined, set thisValue to globalObj.
if (this_value == nullptr)
this_value = global_object;
// Non-standard
VERIFY(this_value);
// 4. Set realmRec.[[GlobalObject]] to globalObj.
m_global_object = global_object;
// 5. Let newGlobalEnv be NewGlobalEnvironment(globalObj, thisValue).
// 6. Set realmRec.[[GlobalEnv]] to newGlobalEnv.
m_global_environment = m_global_object->heap().allocate_without_realm<GlobalEnvironment>(*global_object, *this_value);
// 7. Return unused.
}
void Realm::visit_edges(Visitor& visitor)
{
visitor.visit(m_intrinsics);
visitor.visit(m_global_object);
visitor.visit(m_global_environment);
}
}