RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-16 20:05:07 +00:00
Code Issues Activity Actions

LibJS: Add a scope object abstraction

Browse source 
Both GlobalObject and LexicalEnvironment now inherit from ScopeObject,
and the VM's call frames point to a ScopeObject chain rather than just
a LexicalEnvironment chain.

This gives us much more flexibility to implement things like "with",
and also unifies some of the code paths that previously required
special handling of the global object.

There's a bunch of more cleanup that can be done in the wake of this
change, and there might be some oversights in the handling of the
"super" keyword, but this generally seems like a good architectural
improvement. :^)
This commit is contained in:
Andreas Kling 2020-11-28 16:02:27 +01:00
parent e1bbc7c075
commit c3fe9b4df8
16 changed files with 241 additions and 92 deletions
Download patch file Download diff file Expand all files Collapse all files

20
Libraries/LibJS/Runtime/ScriptFunction.cpp
View file

@ -47,17 +47,17 @@ static ScriptFunction* typed_this(VM& vm, GlobalObject& global_object)
return static_cast<ScriptFunction*>(this_object);
}
ScriptFunction* ScriptFunction::create(GlobalObject& global_object, const FlyString& name, const Statement& body, Vector<FunctionNode::Parameter> parameters, i32 m_function_length, LexicalEnvironment* parent_environment, bool is_strict, bool is_arrow_function)
ScriptFunction* ScriptFunction::create(GlobalObject& global_object, const FlyString& name, const Statement& body, Vector<FunctionNode::Parameter> parameters, i32 m_function_length, ScopeObject* parent_scope, bool is_strict, bool is_arrow_function)
{
return global_object.heap().allocate<ScriptFunction>(global_object, global_object, name, body, move(parameters), m_function_length, parent_environment, *global_object.function_prototype(), is_strict, is_arrow_function);
return global_object.heap().allocate<ScriptFunction>(global_object, global_object, name, body, move(parameters), m_function_length, parent_scope, *global_object.function_prototype(), is_strict, is_arrow_function);
}
ScriptFunction::ScriptFunction(GlobalObject& global_object, const FlyString& name, const Statement& body, Vector<FunctionNode::Parameter> parameters, i32 m_function_length, LexicalEnvironment* parent_environment, Object& prototype, bool is_strict, bool is_arrow_function)
ScriptFunction::ScriptFunction(GlobalObject& global_object, const FlyString& name, const Statement& body, Vector<FunctionNode::Parameter> parameters, i32 m_function_length, ScopeObject* parent_scope, Object& prototype, bool is_strict, bool is_arrow_function)
: Function(prototype, is_arrow_function ? vm().this_value(global_object) : Value(), {})
, m_name(name)
, m_body(body)
, m_parameters(move(parameters))
, m_parent_environment(parent_environment)
, m_parent_scope(parent_scope)
, m_function_length(m_function_length)
, m_is_strict(is_strict)
, m_is_arrow_function(is_arrow_function)
@ -84,7 +84,7 @@ ScriptFunction::~ScriptFunction()
void ScriptFunction::visit_edges(Visitor& visitor)
{
Function::visit_edges(visitor);
visitor.visit(m_parent_environment);
visitor.visit(m_parent_scope);
}
LexicalEnvironment* ScriptFunction::create_environment()
@ -102,11 +102,13 @@ LexicalEnvironment* ScriptFunction::create_environment()
}
}
auto* environment = heap().allocate<LexicalEnvironment>(global_object(), move(variables), m_parent_environment, LexicalEnvironment::EnvironmentRecordType::Function);
auto* environment = heap().allocate<LexicalEnvironment>(global_object(), move(variables), m_parent_scope, LexicalEnvironment::EnvironmentRecordType::Function);
environment->set_home_object(home_object());
environment->set_current_function(*this);
if (m_is_arrow_function)
environment->set_new_target(m_parent_environment->new_target());
if (m_is_arrow_function) {
if (m_parent_scope->is_lexical_environment())
environment->set_new_target(static_cast<LexicalEnvironment*>(m_parent_scope)->new_target());
}
return environment;
}
@ -144,7 +146,7 @@ Value ScriptFunction::execute_function_body()
argument_value = js_undefined();
}
arguments.append({ parameter.name, argument_value });
vm.current_environment()->set(global_object(), parameter.name, { argument_value, DeclarationKind::Var });
vm.current_scope()->put_to_scope(parameter.name, { argument_value, DeclarationKind::Var });
}
return interpreter->execute_statement(global_object(), m_body, move(arguments), ScopeType::Function);