When the compiler fails to find an overload with suitable parameter or return types, it often attaches a note listing the available overloads so that users can find the one they meant to use. The overloads are currently ordered in a way that depends on the order they were declared, so swift-evolve would sometimes cause tests involving these diagnostics to fail.
This change emits the list in a textually-sorted order instead. The names were already being sorted as they were inserted into a std::set, so this shouldn’t significantly slow down the diagnostic.
This builds on initial commit which added `RelabelArguments` fix
to the solver that only supported `missingLabels` at that moment,
but now it supports all three posibilities - missing/extraneous and
incorrect labels.
...and Swift 4 versions in Swift 3, and Swift 2 and "raw" versions in
both. This allows the compiler to produce sensible errors and fix-its
when someone uses the "wrong" name for an API. The diagnostics
certainly have room to improve, but at least the essentials are there.
Note that this commit only addresses /top-level/ decls, i.e. those
found by lookup into a module. We're still limited to producing all
members of a nominal type up front, so that'll require a slightly
different approach.
Part of rdar://problem/29170671
Previously, for an Objective-C class method declaration that could be
imported as init, we were making 4 decls:
1) The Swift 2 init
2) The Swift 2 class method decl (suppressing init formation)
3) The Swift 3 init (omitting needless words)
4) The Swift 3 class method decl (suppressing init formation and
omitting needless words)
Decls 1), 2), and 4) exist for diagnostics and redirect the user at
3). But, 4) does not correspond to any actual Swift version name and
producing it correctly would require the user to understand how
omit-needless-words and other importer magic operates. It provides
very limited value and more importantly gets in the way of future
Clang importer refactoring. We’d like to turn Decl importing into
something that is simpler and language-version parameterized, but
there is no real Swift version to correspond to decl 4).
Therefore we will be making the following decls:
1) The "raw" decl, the name as it would appear to the user if they
copy-pasted Objective-C code
2) The name as it appeared in Swift 2 (which could be an init)
3) The name as it appeared in Swift 3 (which could be an init and omit
needless words)
This aligns with the language versions we want to import as in the
future: raw, swift2, swift3, …, and current.
Note that swift-ide-test prunes decls that are unavailable in the
current Swift version, so the Swift 2 non-init decls are not printed
out, though they are still present. Tests were updated and expanded to
ensure this was still the case.
