The replacement types in a SubstitutionMap correspond with the generic
parameters of its generic signature, so replace the DenseMap storage
with a flat array of Types, one element for each generic parameter.
If SubstitutionMap is asked to form a substitution for a generic
parameter that has been made concrete by the generic signature,
substitute into the concrete type. This allows us to better deal with
non-canonical types.
Implement exhaustiveness checking in Sema with rich error messages. The
algorithm used is a variant of the one described in Fengyun Liu's paper
"A Generic Algorithm for Checking Exhaustivity of Pattern Matching"
published in the EPFL conference, and Luc Maranget's seminal paper
"Warnings for Pattern Matching"
The Space Engine views pattern matching as a problem of projecting the
scrutinee of a pattern-match into a "Space", then iteratively
constructing a Space from the cases. Taking the difference of this
master space and the covered spaces yields the "holes" left over or
reveals a completely covered space.
The algorithm also extends trivially to redundancy checks in patterns,
but that check is already implemented in SILGen and this algorithm does
not improve upon it.
conversions and extend lifetimes over the call.
Apply this logic to string-to-pointer conversions as well as
array-to-pointer conversions.
Fix the AST verifier to not blow up on optional pointer conversions,
and make sure we SILGen them correctly. There's still an AST bug
here, but I'll fix that in a follow-up patch.
Previously we had more ad hoc logic that tried to decide if it was
worth desugaring a type based on its structure. Now we instead look
for a typealias that might actually benefit from desugaring, and if
we don't find one we won't show the 'aka' note.
Infer same-type requirements among same-named associated
types/typealiases within inherited protocols. This is more staging; it
doesn't really have teeth until we stop wiring together these types as
part of lookup.
* Allow CodingKey conformance to be automatically derived for enums
which have no raw type (with no associated values) and which have
a raw type of String or Int.
* Allow Encodable and Decodable conformance to be automatically derived
for classes and structs with Encodable/Decodable properties
* Add initial unit tests for verifying derived conformance
SubstitutionMap::lookupConformance() would map archetypes out
of context to compute a conformance path. Do the same thing
in SubstitutionMap::lookupSubstitution().
The DenseMap of replacement types in a SubstitutionMap now
always has GenericTypeParamTypes as keys.
This simplifies some code and brings us one step closer to
a more efficient representation of SubstitutionMaps.
(which can happen if an imported class has un-importable initializers)
Our initializer model guarantees that it's safe to inherit convenience
initializers when a subclass has implemented all designated
initializers, since each convenience initializer will be implemented
by calling one of the designated initializers. If one of the
designated initializers /can't/ be implemented in Swift, however,
then inheriting the convenience initializer would not be safe.
This is potentially a source-breaking change, so the importer will
only actually record that it failed to import something in when
compiling in Swift 4 mode.
rdar://problem/31563662
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
We can get partially-validated ASTs when they are created by the Clang
importer, but not otherwise needed or after new code can be
introduced. Avoid doing the "checked" verification on such ASTs, to
make assertions-enabled builds more useful for testing.
This is the wrong long-term solution: the AST verifier should tolerate
partially-type-checked ASTs at a finer granularity, but doing so is a
larger project than I can take on at the moment.
