The `__future__` we relied on is now, where the 3 specific things are
all included [since Python 3.0](https://docs.python.org/3/library/__future__.html):
* absolute_import
* print_function
* unicode_literals
* division
These import statements are no-ops and are no longer necessary.
There was a window where the PrimaryAssociatedTypes feature guarded the old
syntax; let's make sure we don't see breakage if a new standard library is
used with an old compiler.
This path was not exercised in the test suite, and when the
PrimaryAssociatedTypes feature finally (incorrectly) triggered it,
it would print '#endifextension'.
- Add driver and frontend option
- Add LangOptions entry
- Ensure driver propagates flag to frontends
- Add feature to `features.json`
Part of rdar://91119995
`@_nonSendable` on a type effectively desugars to an unavailable
extension that provides (`@unchecked`) conformance to the `Sendable`
protocol. Make sure we copy over platform availability so that the
extension does not promise greater availability than the type it extends.
Fixes rdar://90330588.
We need to check the feature availability of _unavailableFromAsync
before it gets picked up in the swift interface file. This updates the
compiler to provide the necessary wrappings for that check.
- have public visibility
- have at most one back deployment version per-platform
- specify an introduced version for each platform with a back deployment version using @available
- have a back deployment version that is greater than the introduced version
- not have conflicting attributes like @_alwaysEmitIntoClient
Refactor to share code with type checking for @_originallyDefinedIn which has overlapping diagnostics.
and make `@_unsafeInheritExecutor` a suppressible feature.
Some language features are required in order to parse a
declaration correctly, but some can safely be ignored.
For the latter, we'd like the module interface to simply
contain the declaration twice, once with the feature and
once without. Some basic support for that was already
added for the SpecializeAttributeWithAvailability feature,
but it didn't interact correctly with required features
that might be checked in the same `#if` clause (it simply
introduced an `#else`), and it wasn't really set up to
allow multiple features to be handled this way. There
were also a few other places that weren't updated to
handle this, presumably because they never coincided
with a `@_specialize` attribute.
Introduce the concept of a suppressible feature, which
is anything that the ASTPrinter can modify the current
PrintOptions in order to suppress. Restructure the
printing of compatibility checks so that we can print
the body multiple times with different settings.
Print required feature checks in an outer `#if...#endif`,
then perform a separate `#if...#else...#endif` within
if we have suppressible features. If there are multiple
suppressible features, check for the most recent first,
on the assumption that it will imply the rest; then
perform subsequent checks with an `#elsif` clause.
This should be a far more solid foundation on which to
build compatibility checks in the future.
`@_unsafeInheritExecutor` needs to be suppressible
because it's been added to some rather important
existing APIs. Simply suppressing the entire decl will
effectively block old tools from using a new SDK to
build many existing projects (if they've adopted
`async`). Dropping the attribute changes the semantics
of these functions, but only if the compiler features
the SE-0338 scheduling change; this is a very narrow
window of main-branch development builds of the tools,
none of which were officially released.
When inferring Sendable for a public, frozen type, that Sendable conformance
becomes part of the contract. Therefore, don't infer this conformance
when any of instance storage is implicitly non-Sendable.
Fixes rdar://88652324.
A scoped-down version of #39307. Implement extension of bound generic types. The important bit here is in TypeCheckGeneric where we now use the underlying type of a typealias and its associated nominal type decl when we're generating substitutions for the extended type.
Put this behind a new experimental flag
-enable-experimental-bound-generic-extensions
Resolves SR-4875
Resolves rdar://17434633
Raw values of enum cases from another module are not specified in the declaration of the enum unless that enum is `@objc`. This meant that `EnumRawValuesRequest` was computing potentially incorrect raw values when the enum declaration supported it and was emitting incorrect diagnostics for other enum decls.
Resolves SR-14355 and rdar://75451691
