The attribute makes the declaration unavailable from the perspective of clients
of the module's public interface and was creating a loophole that admitted
inappropriate unavailability.
A protocol conformance witness must be as available as its requirement. In
Swift 6.1 and earlier, the conformance checker failed to note that witnesses in
unavailable extensions are unavailable. That bug was fixed by a previous
change, but there was no test case covering it so the difference in behavior
was not acknowledged.
Related to rdar://143466010.
It should not be possible to mark an associated type declaration unavailable
since doing so does not have an effect on how a conformance interacts with its
associated types.
Some editors use diagnostics from SourceKit to replace build issues. This causes issues if the diagnostics from SourceKit are formatted differently than the build issues. Make sure they are rendered the same way, removing most uses of `DiagnosticsEditorMode`.
To do so, always emit the `add stubs for conformance` note (which previously was only emitted in editor mode) and remove all `; add <something>` suffixes from notes that state which requirements are missing.
rdar://129283608
In https://github.com/apple/swift/pull/63898 conformance requirement
typechecking was relaxed to allow unavailable decls to witness conformance
requirements as long as the conforming nominal was also unavailable. However,
only nominals that were directly marked unavailable were accepted. Nominals
that are declared in unavailable scopes should also be allowed to have
unavailable wintesses.
Resolves rdar://107052715
That is, if there's a problem with a witness, and the witness comes
from a different extension from the conformance (or the original type,
when the conformance is on an extension), put the main diagnostic on
the conformance, with a note on the witness. This involves some
shuffling and rephrasing of existing diagnostics too.
There's a few reasons for this change:
- More context. It may not be obvious why a declaration in file
A.swift needs to be marked 'public' if you can't see the conformance
in B.swift.
- Better locations for imported declarations. If you're checking a
conformance in a source file but the witness came from an imported
module, it's better to put the diagnostic on the part you have
control over. (This is especially true in Xcode, which can't display
diagnostics on imported declarations in the source editor.)
- Plays better with batch mode. Without this change, you can have
diagnostics being reported in file A.swift that are tied to a
conformance declared in file B.swift. Of course the contents of
A.swift also affect the diagnostic, but compiling A.swift on its
own wouldn't produce the diagnostic, and so putting it there is
problematic.
The change does in some cases make for a worse user experience,
though; if you just want to apply the changes and move on, the main
diagnostic isn't in the "right place". It's the note that has the info
and possible fix-it. It's also a slightly more complicated
implementation.
Swift 3 allowed a requirement to be satisfied by an unavailable
witness, which doesn't make sense. We've been warning about it in
Swift 3 for a while; make it an error in Swift 4.
This came out of today's language review meeting.
The intent is to match #available with the attribute
that describes availability.
This is a divergence from Objective-C.
Swift SVN r28484
Previously, we attempted to infer @objc-ness based on conformance, but
doing so is fraught with ordering dependencies, and just doesn't work
in the general case. Among other crimes, this allowed us to
retroactively mark a non-@objc method from an imported module as
@objc... even though nobody would ever then emit the @objc entry
points for it.
Fixes the rest of rdar://problem/18383574.
Swift SVN r24831
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
attribute is a "modifier" of a decl, not an "attribute" and thus shouldn't
be spelt with an @ sign. Teach the parser to parse "@foo" but reject it with
a nice diagnostic and a fixit if "foo" is a decl modifier.
Move 'dynamic' over to this (since it simplifies some code), and switch the
@optional and @required attributes to be declmodifiers (eliminating their @'s).
Swift SVN r19787
- Change the parser to accept "objc" without an @ sign as a contextual
keyword, including the dance to handle the general parenthesized case.
- Update all comments to refer to "objc" instead of "@objc".
- Update all diagnostics accordingly.
- Update all tests that fail due to the diagnostics change.
- Switch the stdlib to use the new syntax.
This does not switch all tests to use the new syntax, nor does it warn about
the old syntax yet. That will be forthcoming. Also, this needs a bit of
refactoring, which will be coming up.
Swift SVN r19555
