This saves having to save and load the parser state.
This could give an incorrect token in some cases where the parser
communicates to the lexer. However this is not applicable in any of the
current usages and this would require one to parse the current token
as normal which is exactly what you don't want to do in that scenario.
Well... sort of. This adds the function itself and all the scaffolding
from the ShadowRealm API (and basically completes its implementation).
However, we do not nearly have enough support for modules and imports,
so we currently pretend whatever was attempted to be imported failed -
once we have HostImportModuleDynamically it should be relatively easy to
complete the implementation.
Step 12 was using `lhs.is_bigint()` instead of `rhs.is_bigint()`,
meaning you got:
```js
1n == Object(1n); // true
Object(1n) == 1n; // false
```
This also adds spec comments to is_loosely_equal.
This is just another workaround, but it should be much more reliable
than Interpreter::realm(), especially when allocating NativeFunctions
and ECMAScriptFunctionObjects: we're guaranteed to have a GlobalObject
at that point, and it likely was set as the GlobalObject of a Realm and
can lead us back to it. We're however not guaranteed that the VM can
give us an Interpreter, which is why functions in LibWeb can be a bit
crashy at the moment.
We use a WeakPtr<Realm> to properly handle the unlikely case where the
Realm goes away after associating a GlobalObject to it.
We'll always need _something_ of this sort if we want to support
OrdinaryFunctionCreate and CreateBuiltinFunction without the explicit
realm argument while no JS is running, because they want to use the
current Realm Record (always in the first and as fallback in the second
case).
The Completion constructor `VERIFY()`s that the passed argument is not
an empty Value, so normal_completion({}) would crash (although it's
currently not being used anywhere).
We want to pass an empty Optional<Value> instead.
This concept is not present in ECMAScript, and it bothers me every time
I see it.
It's only used by WrapperGenerator, and even there only relevant in two
places, so let's fully remove it from LibJS and use a simple ternary
expression instead:
cpp_name = js_name.is_null() && legacy_null_to_empty_string
? String::empty()
: js_name.to_string(global_object);