RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-06-01 09:18:11 +00:00
Code Issues Activity Actions

LibJS: Start implementing spec-compliant variable bindings

Browse source 
This patch adds the concept of variable bindings to the various
environment record classes. The bindings are not yet hooked up to
anything, this is just fleshing out all the operations.

Most of this is following the spec exactly, but in a few cases we are
missing the requisite abstract operations to do the exact right thing.
I've added FIXME's in those cases where I noticed it.
This commit is contained in:
Andreas Kling 2021-06-23 12:26:37 +02:00
parent 2822da8c8f
commit 9d49a5478a
8 changed files with 360 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

94
Userland/Libraries/LibJS/Runtime/DeclarativeEnvironmentRecord.cpp
View file

@ -51,6 +51,8 @@ void DeclarativeEnvironmentRecord::visit_edges(Visitor& visitor)
Base::visit_edges(visitor);
for (auto& it : m_variables)
visitor.visit(it.value.value);
for (auto& it : m_bindings)
visitor.visit(it.value.value);
}
Optional<Variable> DeclarativeEnvironmentRecord::get_from_environment_record(FlyString const& name) const
@ -68,4 +70,96 @@ bool DeclarativeEnvironmentRecord::delete_from_environment_record(FlyString cons
return m_variables.remove(name);
}
// 9.1.1.1.1 HasBinding ( N ), https://tc39.es/ecma262/#sec-declarative-environment-records-hasbinding-n
bool DeclarativeEnvironmentRecord::has_binding(FlyString const& name) const
{
return m_bindings.contains(name);
}
void DeclarativeEnvironmentRecord::create_mutable_binding(GlobalObject&, FlyString const& name, bool can_be_deleted)
{
auto result = m_bindings.set(name,
Binding {
.value = {},
.strict = false,
.mutable_ = true,
.can_be_deleted = can_be_deleted,
.initialized = false,
});
VERIFY(result == AK::HashSetResult::InsertedNewEntry);
}
void DeclarativeEnvironmentRecord::create_immutable_binding(GlobalObject&, FlyString const& name, bool strict)
{
auto result = m_bindings.set(name,
Binding {
.value = {},
.strict = strict,
.mutable_ = false,
.can_be_deleted = false,
.initialized = false,
});
VERIFY(result == AK::HashSetResult::InsertedNewEntry);
}
void DeclarativeEnvironmentRecord::initialize_binding(GlobalObject&, FlyString const& name, Value value)
{
auto it = m_bindings.find(name);
VERIFY(it != m_bindings.end());
VERIFY(it->value.initialized == false);
it->value.value = value;
it->value.initialized = true;
}
void DeclarativeEnvironmentRecord::set_mutable_binding(GlobalObject& global_object, FlyString const& name, Value value, bool strict)
{
auto it = m_bindings.find(name);
if (it == m_bindings.end()) {
if (strict) {
global_object.vm().throw_exception<ReferenceError>(global_object, ErrorType::UnknownIdentifier, name);
return;
}
create_mutable_binding(global_object, name, true);
initialize_binding(global_object, name, value);
return;
}
if (it->value.strict)
strict = true;
if (!it->value.initialized) {
global_object.vm().throw_exception<ReferenceError>(global_object, ErrorType::BindingNotInitialized, name);
return;
}
if (it->value.mutable_) {
it->value.value = value;
} else {
if (strict) {
global_object.vm().throw_exception<TypeError>(global_object, ErrorType::InvalidAssignToConst);
}
}
}
Value DeclarativeEnvironmentRecord::get_binding_value(GlobalObject& global_object, FlyString const& name, bool)
{
auto it = m_bindings.find(name);
VERIFY(it != m_bindings.end());
if (!it->value.initialized) {
global_object.vm().throw_exception<ReferenceError>(global_object, ErrorType::BindingNotInitialized, name);
return {};
}
return it->value.value;
}
bool DeclarativeEnvironmentRecord::delete_binding(GlobalObject&, FlyString const& name)
{
auto it = m_bindings.find(name);
VERIFY(it != m_bindings.end());
if (!it->value.can_be_deleted)
return false;
m_bindings.remove(it);
return true;
}
}