This was defined twice, despite being the very same thing:
- ClassElement::ClassFieldDefinition
- ECMAScriptFunctionObject::InstanceField
Move the former to a new header and use it everywhere. Also update the
define_field() AO to take a single field instead of separate name and
initializer arguments.
This helps make the overall codebase consistent. `class_name()` in
`Kernel` is always `StringView`, but not elsewhere.
Additionally, this results in the `strlen` (which needs to be done
when printing or other operations) always being computed at
compile-time.
Being really close to Object.prototype.valueOf() name wise makes this
unnecessarily confusing - while it sometimes serves as the
implementation of a valueOf() function, it's an abstraction which the
spec doesn't have.
Use the appropriate getters to retrieve specific internal slots instead,
most commonly [[FooData]] from the primitive wrapper objects.
For the Object class specifically, use the Value(Object*) ctor instead.
This is just factoring out step "9. Set O.[[Prototype]] to V." of
10.1.2 [[SetPrototypeOf]] into its own method so that we don't have to
use internal_set_prototype_of() for setting an object prototype in all
cases.
The way that transition avoidance (foo_without_transition) was
implemented led to shapes being unshareable and caused shape explosion
instead, precisely what we were trying to avoid.
This patch removes all the attempts to avoid transitioning shapes, and
instead *adds* transitions when changing an object's prototype.
This makes transitions flow naturally, and as a result we end up with
way fewer shape objects in real-world situations.
When we run out of big problems, we can get back to avoiding transitions
as an optimization, but for now, let's avoid ballooning our processes
with a unique shape for every object.
Before this we used an ad-hoc combination of references and 'variables'
stored in a hashmap. This worked in most cases but is not spec like.
Additionally hoisting, dynamically naming functions and scope analysis
was not done properly.
This patch fixes all of that by:
- Implement BindingInitialization for destructuring assignment.
- Implementing a new ScopePusher which tracks the lexical and var
scoped declarations. This hoists functions to the top level if no
lexical declaration name overlaps. Furthermore we do checking of
redeclarations in the ScopePusher now requiring less checks all over
the place.
- Add methods for parsing the directives and statement lists instead
of having that code duplicated in multiple places. This allows
declarations to pushed to the appropriate scope more easily.
- Remove the non spec way of storing 'variables' in
DeclarativeEnvironment and make Reference follow the spec instead of
checking both the bindings and 'variables'.
- Remove all scoping related things from the Interpreter. And instead
use environments as specified by the spec. This also includes fixing
that NativeFunctions did not produce a valid FunctionEnvironment
which could cause issues with callbacks and eval. All
FunctionObjects now have a valid NewFunctionEnvironment
implementation.
- Remove execute_statements from Interpreter and instead use
ASTNode::execute everywhere this simplifies AST.cpp as you no longer
need to worry about which method to call.
- Make ScopeNodes setup their own environment. This uses four
different methods specified by the spec
{Block, Function, Eval, Global}DeclarationInstantiation with the
annexB extensions.
- Implement and use NamedEvaluation where specified.
Additionally there are fixes to things exposed by these changes to eval,
{for, for-in, for-of} loops and assignment.
Finally it also fixes some tests in test-js which where passing before
but not now that we have correct behavior :^).
