Introduction, deprecation, and obsoleteion ranges should only be returned by
the accessors on `SemanticAvailableAttr` when the attribute actually has an
affect on the corresponding kind of availability.
Introduce `SemanticAvailableAttr` conveniences to compute the deprecated and
obsoleted ranges for an attribute and ensure they remap versions when needed.
Implement lookup of availability domains for identifiers on
`AvailabilityDomainOrIdentifier`. Add a bit to that type which represents
whether or not lookup has already been attempted. This allows both
`AvailableAttr` and `AvailabilitySpec` to share a common implementation of
domain lookup.
The previous algorithm failed to correctly handle the cases where some grouped
`@available` attributes could be marked invalid prior to type checking
attributes.
In order to unblock resolution of availability domains during type-checking
instead of parsing, diagnostics about missing or superfluous wildcards in
availability specification lists need to move to Sema.
Translate macOS 10.16 to macOS 11 on-demand when calling
`SemanticAvailableAttr` version accessors. This removes the need for
`AvailableAttr` to have mutable version members that
`SemanticAvailableAttrRequest` can update.
Eventually, querying the `AvailabilityDomain` associated with an
`AvailabilitySpec` will require invoking a request that takes a `DeclContext`.
This means that any diagnostics related to the domain identified by an
`AvailabilitySpec` need to be emitted during type-checking rather than parsing.
This change migrates several `AvailabilitySpec` diagnostics from Parse to Sema
to unblock further work.
There are a few places in the AST where we use `uint64_t` as
`ArrayRef`'s size type. Even though of these `uint64_t` size fields are
actually defined as bitfields with a maximum value of 32, but
unfortunately it's not taken into account and clang complains about
the implicit cast.
The same attempt was made in 073905b573,
but several new places were added since then.
Representing introduced, deprecated, and obsoleted versions at rest as optional
version tuples is redundant, since the empty version tuple already represents
"version not present".
NFC.
This request will finish type checking an AvailableAttr by resolving its domain
and then enforcing any restrictions that the domain has on the attribute, like
disallowing version specifications.
This change just introduces the request and plumbs it through. NFC.
Most of the compiler should use SemanticAvailableAttr instead. In contexts like
ASTDumper where a semantic attribute is unavailable use accessors on
AvailableAttr.
NFC.
Now that AvailableAttr has storage for its cached AvailabilityDomain, it's no
longer necessary to store an AvailabilityDomain inline in
SemanticAvailableAttr.
NFC.
It was difficult to preserve the existing, buggy behavior of availability
attribute inference with respect to attributes specifying availability for
non-platform-specific domains. Instead, this change improves attribute merging
by tracking every domain independently, and only merging attributes from the
same domain.
AvailableAttr::Kind and AvailabilityDomain are designed to replace
PlatformAgnosticAvailabilityKind, allowing AvailableAttr to more flexibly model
availability for arbitrary domains. For now, the new constructor just
translates its inputs into inputs for the existing constructor. Once all of the
callers of the existing AvailableAttr constructor have been updated to use the
new constructor, the representation of AvailableAttr will be updated to store
the new properties.
