This will allow us to use these traits for other hash-based containers
(like Map). This commit also adds a special case for negative zero
values, because while the equality check used same_value_zero which is
negative/positive zero insensitive, the hash was not.
This counter is increased each time a synchronous execution sequence
completes, and will allow us to emulate the abstract operations
AddToKeptObjects & ClearKeptObjects efficiently.
This is very similar to Object::define_native_property, but here the
native functions are exported as standalone JS getter and setter
functions, instead of being transparently called by interactions with
the property.
The fact that they *are* subclasses is an implementation detail and
should not be highlighted. The spec calls these NativeErrors, so let's
use that.
Also added a comment explaining *why* they inherit from Error - I was
about to change that :^)
20.5.1.1 Error ( message )
When the Error function is called with argument message, the
following steps are taken:
[...]
3b. Let msgDesc be the PropertyDescriptor {
[[Value]]: msg,
[[Writable]]: true,
[[Enumerable]]: false,
[[Configurable]]: true
}.
3c. Perform ! DefinePropertyOrThrow(O, "message", msgDesc).
The FunctionPrototype is correct for ErrorConstructor itself:
20.5.2 Properties of the Error Constructor
The Error constructor:
- has a [[Prototype]] internal slot whose value is
%Function.prototype%.
However, not for all the other "NativeError" constructors:
20.5.6.2 Properties of the NativeError Constructors
Each NativeError constructor:
- has a [[Prototype]] internal slot whose value is %Error%.
Non-RangeError exceptions can be thrown by user implementations of
valueOf (which are called by to_index), and the specification disallows
changing the type of the thrown error.
The second argument (the default constructor) and the return value have
to be constructors (as a result functions), so we can require that
explicitly by using appropriate types.
More specifically, Array.prototype.splice. Additionally adds a missing
exception check to the array creation and a link to the spec.
Fixes create-non-array-invalid-len.js in the splice tests in test262.
This test timed out instead of throwing an "Invalid array length"
exception.
We already have two separate implementations of this, so let's do it
properly. The optional value type check is done by a callback function
that returns Result<void, ErrorType> - value type accepted or message
for TypeError, that is.
This was creating a ton of pointless busywork for the garbage collector
and can be avoided simply by tolerating that the current call frame has
a null scope object for the duration of a NativeFunction activation.
This makes sure that is<Set> checks done on the Set prototype instead of
on Set instances return false, thereby emulating the behaviour of the
RequireInternalSlot abstract operation.
Instead of using Strings in the bytecode ops this adds a global string
table to the Executable struct which individual operations can refer
to using indices. This brings bytecode ops one step closer to being
pointer free.
While this implementation should be complete it is based on HashTable's
iterator, which currently follows bucket-order instead of the required
insertion order. This can be simply fixed by replacing the underlying
HashTable member in Set with an enhanced one that maintains a linked
list in insertion order.
