With one caveat: in the PreparePartialTemporalFields AO I made a change
to fix a spec issue that would require the input object to always have a
month or monthCode property.
This is tracked in https://github.com/tc39/proposal-temporal/issues/1910
and may get accepted as-is, in which case we simply need to remove the
NOTE comment.
We move the input string into this field to avoid a string copy, so we
must do this step last to avoid using any views into it (note that
match.view here is a view into this string).
Two issues:
- The format string said "{:9}", which left-pads with spaces and not
zeros as required
- Even when correcting that, we were not accounting for step 11 b:
"Set fraction to the longest possible substring of fraction starting
at position 0 and not ending with the code unit 0x0030 (DIGIT ZERO)."
We can safely use trim() for that as the formatted string is known to
not contain only zeros (which would leave the left-most in place).
Also adds tests for "UTC" and various numeric offsets.
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 patch implements:
- Spec compliant [[Call]] and [[Construct]] internal slots, as virtual
FunctionObject::internal_{call,construct}(). These effectively replace
the old virtual FunctionObject::{call,construct}(), but with several
advantages:
- Clear and consistent naming, following the object internal methods
- Use of completions
- internal_construct() returns an Object, and not Value! This has been
a source of confusion for a long time, since in the spec there's
always an Object returned but the Value return type in LibJS meant
that this could not be fully trusted and something could screw you
over.
- Arguments are passed explicitly in form of a MarkedValueList,
allowing manipulation (BoundFunction). We still put them on the
execution context as a lot of code depends on it (VM::arguments()),
but not from the Call() / Construct() AOs anymore, which now allows
for bypassing them and invoking [[Call]] / [[Construct]] directly.
Nothing but Call() / Construct() themselves do that at the moment,
but future additions to ECMA262 or already existing web specs might.
- Spec compliant, standalone Call() and Construct() AOs: currently the
closest we have is VM::{call,construct}(), but those try to cater to
all the different function object subclasses at once, resulting in a
horrible mess and calling AOs with functions they should never be
called with; most prominently PrepareForOrdinaryCall and
OrdinaryCallBindThis, which are only for ECMAScriptFunctionObject.
As a result this also contains an implicit optimization: we no longer
need to create a new function environment for NativeFunctions - which,
worth mentioning, is what started this whole crusade in the first place
:^)
The old name is the result of the perhaps somewhat confusingly named
abstract operation OrdinaryFunctionCreate(), which creates an "ordinary
object" (https://tc39.es/ecma262/#ordinary-object) in contrast to an
"exotic object" (https://tc39.es/ecma262/#exotic-object).
However, the term "Ordinary Function" is not used anywhere in the spec,
instead the created object is referred to as an "ECMAScript Function
Object" (https://tc39.es/ecma262/#sec-ecmascript-function-objects), so
let's call it that.
The "ordinary" vs. "exotic" distinction is important because there are
also "Built-in Function Objects", which can be either implemented as
ordinary ECMAScript function objects, or as exotic objects (our
NativeFunction).
More work needs to be done to move a lot of infrastructure to
ECMAScriptFunctionObject in order to make FunctionObject nothing more
than an interface for objects that implement [[Call]] and optionally
[[Construct]].
Currently, we have NotA and NotAn, to be used dependent on whether the
following word begins with a vowel or not. To avoid this, change the
wording on NotA to be independent of this context.
