Semantically, these are not superclass/refined-protocol members.
If I have a generic parameter <T : P & Q>, then when looking at
a value of type T, members of P and Q are at the same "level" as
if I had a value of type (P & Q).
For:
class MyClass {
func foo(x: SomeType)
func foo(x: OtherType)
}
func test(obj: MyClass) {
obj.foo(x: <HERE>)
}
Type checker doesn't keep overloaded choices for 'obj.foo' in the AST
after typechecking. Code completion need to lookup members to collect
possible parameter types.
At the time this logic was introduced in 8f83ca67, `<expr>.<keyword>` wasn't
allowed. Now that SE-0071 has been implemented, this logic doesn't provide any
positive effects.
The patch that nailed down our semantics here missed an additional case that
required a compatibility hack: a property on a generic type and a same-named one
in an (unconstrained) extension:
struct Foo<T> {
var x: Int { return 0 }
}
extension Foo {
var x: Bool { return false }
}
Fixes rdar://problem/40685642.
Currently we only give subscripts and var decls custom overload types if they're in generic extensions. However, because we give them no custom overload type in any other case, we don't detect for example a conflict with a previous declaration in the body of the extended type.
This commit changes the overload type logic such that properties and subscripts are always given custom overload types, which is determined by:
- The interface type of the decl (for subscripts only; as variables cannot be overloaded by type)
- The 'self' type of the context, if any
- The generic signature of the context, if any
Additionally, this commit adds a new `swift::conflicting` overload to ensure that different declarations always conflict even if their overload types are different.
Resolves SR-7249, SR-7250 & SR-7251.
Stop creating ImplicitlyUnwrappedOptional<T> so that we can remove it
from the type system.
Enable the code that generates disjunctions for Optional<T> and
rewrites expressions based on the original declared type being 'T!'.
Most of the changes supporting this were previously merged to master,
but some things were difficult to merge to master without actually
removing IUOs from the type system:
- Dynamic member lookup and dynamic subscripting
- Changes to ensure the bridging peephole still works
Past commits have attempted to retain as much fidelity with how we
were printing things as possible. There are some cases where we still
are not printing things the same way:
- In diagnostics we will print '?' rather than '!'
- Some SourceKit and Code Completion output where we print a Type
rather than Decl.
Things like module printing via swift-ide-test attempt to print '!'
any place that we now have Optional types that were declared as IUOs.
There are some diagnostics regressions related to the fact that we can
no longer "look through" IUOs. For the same reason some output and
functionality changes in Code Completion. I have an idea of how we can
restore these, and have opened a bug to investigate doing so.
There are some small source compatibility breaks that result from
this change:
- Results of dynamic lookup that are themselves declared IUO can in
rare circumstances be inferred differently. This shows up in
test/ClangImporter/objc_parse.swift, where we have
var optStr = obj.nsstringProperty
Rather than inferring optStr to be 'String!?', we now infer this to
be 'String??', which is in line with the expectations of SE-0054.
The fact that we were only inferring the outermost IUO to be an
Optional in Swift 4 was a result of the incomplete implementation of
SE-0054 as opposed to a particular design. This should rarely cause
problems since in the common-case of actually using the property rather
than just assigning it to a value with inferred type, we will behave
the same way.
- Overloading functions with inout parameters strictly by a difference
in optionality (i.e. Optional<T> vs. ImplicitlyUnwrappedOptional<T>)
will result in an error rather than the diagnostic that was added
in Swift 4.1.
- Any place where '!' was being used where it wasn't supposed to be
allowed by SE-0054 will now treat the '!' as if it were '?'.
Swift 4.1 generates warnings for these saying that putting '!'
in that location is deprecated. These locations include for example
typealiases or any place where '!' is nested in another type like
`Int!?` or `[Int!]`.
This commit effectively means ImplicitlyUnwrappedOptional<T> is no
longer part of the type system, although I haven't actually removed
all of the code dealing with it yet.
ImplicitlyUnwrappedOptional<T> is is dead, long live implicitly
unwrapped Optional<T>!
Resolves rdar://problem/33272674.
Redeclaration checking was validating all declarations with the same
base name as the given declaration (and in the same general nominal
type), even when it was trivial to determine that the declarations
could not be conflicting. Separate out the easy structural checks
(based on kind, full name, instance vs. non-instance member, etc.) and
perform those first, before validation.
Fixes SR-6558, a case where redeclaration checking caused some
unnecessary recursion in the type checker.
Constructor call patterns already get a real priority, but because of
the way we do function call patterns we don't have enough information,
and previously we were setting it to "expression specific", which is
unnecessarily high, particularly since functions (unlike inits) have
other better ways to code-complete already.
rdar://31113161
When completing
Foo(<here>
We will now provide
bar: <#value#>
instead of
bar: <#value#>)
Inserting the rparen caused some problems in practice:
* the old behaviour optimized for typing Foo(<complete> instead of
Foo(<complete>), which can conflict with user behaviours or ...
* in editors with automatic brace-matching, we often conflicted with the
editor, leading to extraneous closing parens
And in general, it is much more predictable for tooling to either insert
matching ( and ) or to not insert either. While this change may not be
ideal For users of editors that do not do automatic brace-matching, I
believe it is still better overall to have to type a missing paren than
to have to delete an extraneous one.
rdar://31113161
The original hope was we could make these heuristics really good, but
since that is not currently in sight (and may never be), we want to be
able to turn them off. For now, just plumb through an internal flag to
control the behaviour. A future change will customize the behaviour in
SourceKit.
rdar://31113161
Also restore some diagnostics in TypeCheckType that should have
migrated with the attributes. In particular, diagnose cases where
we have @autoclosure with any function type repr with a non-Void
input type.
Resolves SR-5296
`FreeTypeVariableBinding::GenericParameters` mode allowed to bind
all free type variables with fresh generic parameter types, which
is incorrect (at least) if there are multiple generic solutions
present, because such parameters couldn't be compared.
This mode was used for code completion, which is now switched to use
`FreeTypeVariableBinding::UnresolvedType` instead.
Substitution into a generic function type produces non-canonical
generic signatures. This functionality should either be removed or be
completely rewritten to properly use the GenericSignatureBuilder. For
now, disable this one client's unsafe use of it.
This does regression code-completion results slightly, where we were
depending on OverrideFilteringConsumer's behavior to filter out some
redundant results. I've captured the work to fix this properly in
rdar://problem/31245556.
There is never any reason for a transform to treat a ParenType
differently from the underlying type itself. Calling the given
function with ParenTypes is a source of bugs where they get
desugared on accident. Make transform() skip the function
entirely for ParenTypes, and remove a spot where we were
checking explicitly.
If a sugared type desugars to a substitutable type, we would
return the replacement type without the sugar. I think in
practice this meant that ParenType would be lost sometimes.
Preserving this correctly is required for an upcoming CSDiag
change.
Note that there's a minor source-breaking change with enum
case constructors here. I've filed <rdar://problem/27261929>
to track sorting it out in Swift 3 mode.
Also an upcoming patch fixes another related issue and adds more
tests for case constructors.
There was a ton of complicated logic here to work around
two problems:
- Same-type constraints were not represented properly in
RequirementReprs, requiring us to store them in strong form
and parse them out when printing type interfaces.
- The TypeBase::getAllGenericArgs() method did not do the
right thing for members of protocols and protocol extensions,
and so instead of simple calls to Type::subst(), we had
an elaborate 'ArchetypeTransformer' abstraction repeated
in two places.
Rewrite this code to use GenericSignatures and
GenericFunctionType instead of old-school GenericParamLists
and PolymorphicFunctionType.
This changes the code completion and AST printer output
slightly. A few of the changes are actually fixes for cases
where the old code didn't handle substitutions properly.
A few others are subjective, for example a generic parameter
list of the form <T : Proto> now prints as <T where T : Proto>.
We can add heuristics to make the output whatever we want
here; the important thing is that now we're using modern
abstractions.
This commit defines the ‘Any’ keyword, implements parsing for composing
types with an infix ‘&’, and provides a fixit to convert ‘protocol<>’
- Updated tests & stdlib for new composition syntax
- Provide errors when compositions used in inheritance.
Any is treated as a contextual keyword. The name ‘Any’
is used emit the empty composition type. We have to
stop user declaring top level types spelled ‘Any’ too.
Completion after dot inside an init (or any other parent expr with a
nominal type) was incorrectly looking at the types of parent expressions
whenever the base type was not a nominal (even an lvalue of a nominal
wasn't working). This code to look at the type of the parent was never
correct, and fortunately the type-checking issues that prompted it to be
added in the first place have since been fixed, so we can just delete
it.
rdar://problem/25773358
Code completion had the ability to use declarations to provide better
code completion results for postfix completions, e.g., calls to
functions/methods, but it wasn't trying to get these declarations from
anywhere. Now, get these declarations from the solution to the
constraint system.
The impetus for this is to use default-argument information from the
declaration rather than the type, but plumbing this information
through also means that we get proper "rethrows" annotations, covered
by <rdar://problem/21010193>, and more specific completions in a
number of other places.
Fixes <rdar://problem/21010193>.
This is a big refactoring of resolveTypeInContext() which makes
the function clearer to understand by merging various special
cases and generalizing the logic for walking parent and superclass
contexts to cover more cases.
This improves typealiases in protocols a bit:
1) Previously a typealias in a protocol either had to be concrete,
or consist of a single path of member types from Self, eg
Self.A.B. Lift this restriction, so we can now write things like
protocol Fireworks {
associatedtype Exploding
typealias Exploder = Exploding -> [Exploding]
}
2) Protocol typealiases can now be accessed via qualified lookup
on concrete types. Getting this working for unqualified lookup
requires further refactorings which will be in a subsequent
patch.
If a declaration is marked deprecated (but not unavailable) we want to
mark it as "not recommended" so that users know this probably isn't what
you want. We already do something like this in Clang code completions of
deprecated ObjC declarations.
rdar://problem/26335424
