This is required for Temporal.Duration.prototype.round(). Subsequently,
this now returns ThrowCompletionOr<Optional<String>>, which brings the
signature in line with that of to_smallest_temporal_unit().
Much nicer! :^)
This is now as defined in the spec. However since we execute async
functions in bytecode by transforming it to a generator function it must
have a prototype for the GeneratorObject. We check whether it is an
async function and in that case use the hardcoded generator object
prototype. This also ensures that user code cannot override this
property thus preventing exposing internal implementation details.
The first step of to_temporal_calendar_with_iso_default() is checking
whether the given value is undefined, so we should actually pass that
instead of unconditionally dereferencing the Optional<String>.
It's not the `to_uint<u8>()` call that would fail, if we have a value
for these productions they will always be valid numbers. We do need to
provide a fallback for when that's not the case and any of them is
undefined, i.e. an empty Optional.
This is the start of a parser for the ISO 8601 grammar used in the
Temporal spec:
https://tc39.es/proposal-temporal/#sec-temporal-iso8601grammar
We will, on purpose, not use a generic ISO 8601 parser from AK or
similar for two reasons:
- Many AOs make specific assumptions about which productions exist and
access them directly, even when they're part of a larger production.
- The spec says "The grammar deviates from the standard given in ISO
8601 in the following ways:" and then lists 17 of such deviations.
Making that work with a general purpose parser is not worth it.
The public API is not being used anywhere yet, but will be in the next
couple of commits. Likewise, the Production enum will be populated with
all the productions accessed directly (e.g. TemporalDateString).
Many thanks to Ali for showing me how to improve my initial approach
full of macros with a nice RAII helper - it's much nicer :^)
Co-Authored-By: Ali Mohammad Pur <mpfard@serenityos.org>
This would return incorrect results for negative inputs. It still does
to some extent, remainder() in step 2 might need to be replaced with
modulo (I opened an issue in tc39/proposal-temporal about that).
When the bytecode interpreter was converted to ThrowCompletionOr<Value>
it then also cleared the vm.exception() making it seem like no exception
was thrown.
Also removed the TRY_OR_DISCARD as that would skip the error handling
parts.
