This reverts commit 25985cb764. For now,
we're trying to avoid spurious non-structural changes to the mangling,
so that the /old/ mangling doesn't appear to change. That doesn't mean
no changes at all, but we can save this one for later.
Enums with the ns_error_domain attribute represent codes for NSError,
which means Swift developers will expect to interact with them in
terms of Error. SE-0112 improved bridging for these enums to generate
a struct with the following form:
struct MyError: Error {
@objc enum Code: RawRepresentable {
case outOfMemory
case fileNotFound
}
var userInfo: [NSObject: AnyObject] { get }
static var outOfMemory: Code { get }
static var fileNotFound: Code { get }
}
where MyError.Code corresponds to the original MyError enum defined in
Objective-C. Until recently, both the enum and the synthesized struct
were marked as having the original enum as their "Clang node", but
that leads to problems: the struct isn't really ObjC-compatible, and
the two decls have the same USR. (The latter had already been worked
around.)
This commit changes the struct to be merely considered a synthesized
"external definition", with no associated Clang node. This meant
auditing everywhere that's looking for a Clang node and seeing which
ones applied to external definitions in general.
There is one regression in quality here: the generated struct is no
longer printed as part of the Swift interface for a header file, since
it's not actually a decl with a corresponding Clang node. The previous
change to AST printing mitigates this a little by at least indicating
that the enum has become a nested "Code" type.
That is, if you have this declaration:
struct Outer {
struct Inner {
// ...
}
}
and you're just printing 'Inner', print it like this:
struct Outer.Inner {
// ...
}
This comes up with the ClangImporter's import-as-member feature, and
is also about to affect how error code enums are imported as well.
This is currently only enabled in certain contexts: always when
printing interfaces, and for types (but not other members) when
printing declarations for Quick Help.
rdar://problem/28208090
Added "-help" option to Options.td
Added also:
* Added "OPT_HELP" case in the main TestOptions.cpp switch. It uses the llvm options help functionality to provide up-to-date help
* Additional "Use -help for assistance" at the end of the error message that appears when calling an unknown option
Added their following tests, respectively::
* usage.swift, and
* wrong_arguments.swift
Extra: FIXME: in TestOptions::printHelp, suggesting a possible expansion for the printHelp option (details in file)
