When attempting to compile Swift 2 code (or any Swift code using the
Swift 2 names) in Swift 3, the compiler diagnostics are often entirely
useless because the names have changed radically enough that one
generally gets "no member named 'foo'" errors rather than a helpful
"'foo' was renamed to 'bar'" error. This makes for a very poor user
experience when (e.g.) trying to move Swift 2 code forward to Swift 3.
To improve the experience, when the Swift 2 and Swift 3 names of an
API differ, the Clang importer will produce a "stub" declaration that
matches the Swift 2 API. That stub will be marked with a synthesized
attribute
@available(unavailable, renamed: "the-swift-3-name")
that enables better diagnostics (e.g., "'foo' is unavailable: renamed
to 'bar') along with Fix-Its (courtesy of @jrose-apple's recent work)
that fix the Swift 2 code to compile in Swift 3.
This change addresses much of rdar://problem/25309323 (concerning QoI
of Swift 2 code compiled with a Swift 3 compiler), but some cleanup
remains.
Even thought raw types are specified in inheritance clauses, their
members are not usable through an enum instance. Thus, there is no
point to synthesize their members.
as well as on parameter decls. Also, tighten up the type checker to look at
parameter types instead of decl attributes in some cases (exposing a type
checker bug).
Still TODO:
- Reject autoclosure/noescape on non-parameter types.
- Move stdlib and other code to use noescape and autoclosure in the right
spot.
- Warn about autoclosure/noescape on parameters decls, with a fixit to move it.
- Upgrade the warning to an error.
D'oh, forgot to resolve a FIXME in my protocol commit. Now working there
too except that it's giving USRs on the original protocol instead of the
extension. It's not clear how to get back to the extension from the
archetype though.
rdar://problem/25128561
Pass through the original Type in addition to the TypeDecl so that we
can distinguish DynamicSelfType with underlying ClassType from just any
old ClassType.
rdar://problem/25158493
Treat it like the static Self type, which is good enough for producing
USRs in CursorInfo. This doesn't handle class dynamic self, which needs
some kind of API change to printTypeRef to make it work.
rdar://problem/25128561
I can't find anything that's actually broken here (symptom would be
annotations showing up ahead of newlines), but be consistent about
going through callPrintStructurePre to be safe.
For now, only do this in SourceKit (printQuickHelpDeclaration), but
there are probably other printing modes that should do this.
rdar://problem/24292226
Move the type callbacks into the respective type/typerepr printers so
taht we get these callbacks even when we print the type directly, or in
a nested fashion. Also make the returntype more explicit than just
"inside a function type", since visiting the function type currently
visits the input argument tuple (which is different than e.g. the
function *decl* printing, which walks the parameter list explicitly).
rdar://problem/24292226
