For every struct type for which the frameworks provides an NSValue category for boxing and unboxing values of that type, provide an _ObjectiveCBridgeable conformance in the Swift overlay that bridges that struct to NSValue, allowing the structs to be used naturally with id-as-Any APIs and Cocoa container classes. This is mostly a matter of gyb-ing out boilerplate using `NSValue.init(bytes:objCType:)` to construct the instance, `NSValue.objCType` to check its type when casting, and `NSValue.getValue(_:)` to extract the unboxed value, though there are a number of special snowflake cases that need special accommodation:
- To maintain proper layering, CoreGraphics structs need to be bridged in the Foundation overlay.
- AVFoundation provides the NSValue boxing categories for structs owned by CoreMedia, but it does so using its own internal subclasses of NSValue, and these subclasses do not interop properly with the standard `NSValue` subclasses instantiated by Foundation. To do the right thing, we therefore have to let AVFoundation provide the bridging implementation for the CoreMedia types, and we have to use its category methods to do so.
- SceneKit provides NSValue categories to box and unbox SCNVector3, SCNVector4, and SCNMatrix4; however, the methods it provides do so in an unusual way. SCNVector3 and SCNVector4 are packaged into `CGRect`s and then the CGRect is boxed using `valueWithCGRect:`. SCNMatrix4 is copied into a CATransform3D, which is then boxed using `valueWithCATransform3D:` from CoreAnimation. To be consistent with what SceneKit does, use its category methods for these types as well, and when casting, check the type against the type encoding SceneKit uses rather than the type encoding of the expected type.
This allows dynamic casting to succeed between tuple types with
different element types, converting each element in turn. Fixes
rdar://problem/19892202.
When printing a tuple via print(...), print tuple labels when they are
available. This is possible now that the runtime metadata properly
stores tuple labels. Fixes rdar://problem/23130016.
Introduce narrow support for tuple/tuple dynamic casts that merely add
or remove labels, but require the element types to match exactly. This
gets us back to allowing the same correct dynamic casts as in Swift
3.0, when labels were completely ignored.
Remove special-casing that makes NSObject fragile since
this messes up layout. The optimization probably has little
practical benefit anyway.
Fixes <https://bugs.swift.org/browse/SR-2586>.
From the Swift documentation:
"If you define an optional variable without providing a default value,
the variable is automatically set to nil for you."
This eliminates a pile of now-dead code in:
* The type checker, where we no longer have special cases for bridging conversions
* The expression ASTs, where we no longer need to distinguish bridging collection up/down casts
* SILGen, which no longer uses
Still to come is the removal of the
_(set|dictionary)Bridge(From|To)ObjectiveC(Conditional)? entrypoints
from the standard library. They're still used by some tests.
Like NSObject, CFType has primitive operations CFEqual and CFHash,
so Swift should allow those types to show up in Hashable positions
(like dictionaries). The most general way to do this was to
introduce a new protocol, _CFObject, and then have the importer
automatically make all CF types conform to it.
This did require one additional change: the == implementation that
calls through to CFEqual is in a new CoreFoundation overlay, but the
conformance is in the underlying Clang module. Therefore, operator
lookup for conformances has been changed to look in the overlay for
an imported declaration (if there is one).
https://bugs.swift.org/browse/SR-2388
Bitcast the AnyObject result to AnyObject?, then call our new helper function, so that we can handle nils without choking. Fixes rdar://problem/27874026.
- If a parameter type is a sugared function type, mark the type
as non-escaping by default. Previously, we were only doing this
if the parameter type was written as a function type, with no
additional sugar.
This means in the following cases, the function parameter type
is now non-escaping:
func foo(f: ((Int) -> Void))
typealias Fn = (Int) -> Void
func foo(f: Fn)
- Also, allow @escaping to be used in the above cases:
func foo(f: @escaping ((Int) -> Void))
typealias Fn = (Int) -> Void
func foo(f: @escaping Fn)
- Diagnose usages of @escaping in inappropriate locations, instead
of just ignoring them.
It is unfortunate that sometimes we end up desugaring the typealias,
but currently there are other cases where this occurs too, such as
qualified lookpu of protocol typealiases with a concrete base
type, and generic type aliases. A more general representation for
sugared types (such as an AttributedType sugared type) would allow
us to solve this in a more satisfactory manner in the future.
However at the very least this patch factors out the common code
paths and adds comments, so it shouldn't be too bad going forward.
Note that this is a source-breaking change, both because @escaping
might need to be added to parameters with a sugared function type,
and @escaping might be removed if it appears somewhere where we
do not mark function types as non-escaping by default.
Previously, we were only able to detect factory initializers
dispatched through class_method. This didn't work for
factory initializers defined in protocol extensions.
The end result would be that we would strong_release an
uninitialized class instance, which could cause crashes.
Fix DI to correctly release the old instance using
dealloc_partial_ref instead.
Fixes <rdar://problem/27713221>.
SIL already does this where necessary, except with foreign throwing
functions; this patch changes Sema and the ClangImporter to give
them an ObjCBool foreign error result type explicitly.
This fixes a problem where calls to functions taking and returning
the C99 _Bool type were miscompiled on Mac OS X x86-64, because
IRGen was conflating the Objective-C BOOL type (which is a signed
char on some platforms) and C99 _Bool (which lowers as the LLVM
i1 type).
Fixes <rdar://problem/26506458> and <rdar://problem/27365520>.
SE-0072 took implicit bridging conversions away, which regressed the ability to express NSDictionaries as dictionary literals and index them using literal keys. Address this by changing the signature of init(dictionaryLiteral:) to use Hashable and Any, and by replacing the subscript from Objective-C with one using _Hashable that does the bridging on the user's behalf. This largely restores the QoI of working with NS collections.
...instead of picking one definition arbitrarily. This comes from the
new "lookup table" design in Swift 3---we no longer just look for any
"visible" (imported) macro definition, but instead need to know them
up front. This works fine when there's only one definition per module,
but for modules like 'OpenGL' on macOS, with mutually-exclusive
submodules 'GL' and 'GL3', the compiler was arbitrarily deciding that
all of the macros the submodules had in common belonged to 'GL'.
The new model tries to decide if it's possible for two modules to be
imported separately, and keeps both macro entries if possible, only
deduplicating equivalent definitions at the last minute (when
importing into Swift). This /still/ doesn't perfectly match the
behavior you'd get in C, where a submodule and its parent module could
theoretically have conflicting definitions and you'd be fine as long
as you only imported one of them, but hopefully (a) it's close enough,
and (b) nobody is doing that. (The Swift compiler will prefer the
definition in the parent module even if the submodule is the only one
imported.)
rdar://problem/26731529
This allows String, Array, Dictionary, and Set to be passed as variadic arguments to Cocoa APIs like NSLog, NSPredicate, stringWithFormat:, etc. rdar://problem/27651717
One minor revision: this lifts the proposed restriction against
overriding a non-open method with an open one. On reflection,
that was inconsistent with the existing rule permitting non-public
methods to be overridden with public ones. The restriction on
subclassing a non-open class with an open class remains, and is
in fact consistent with the existing access rule.
* [ClangImporter] Remove importer-based NS stripping.
As Tony puts it, in the end we wound up with more Foundation
declarations imported as members or keeping "NS" than those that
dropped it, and any further decisions will be made on a case-by-case
basis. Move all of the existing cases of prefix-stripping into
Foundation's API notes and drop the logic from the compiler.
Tested by dumping the generated interface for Foundation and its
submodules for both macOS and the iOS simulator, and comparing the
results. A few cases did slip through here because of the interaction
between "SwiftName" and "Availability: nonswift".
The next commit will re-add "NS" to some stragglers that we missed.
rdar://problem/26880017
* APINotes: Add "NS" back to a few types.
NSKeyedUnarchiverDelegate
NSKeyedArchiverDelegate
NSTextCheckingTypes
NSBinarySearchingOptions
NSEnumerationOptions
NSSortOptions
More rdar://problem/26880017
* Remove now-redundant SwiftNames from API notes.
No change observed in the generated interface of Foundation and its
submodules.
Finishes rdar://problem/26880017.
Implements part of SE-0110. Single argument in closures will not be accepted if
there exists explicit type with a number of arguments that's not 1.
```swift
let f: (Int, Int) -> Void = { x in } // this is now an error
```
Note there's a second part of SE-0110 which could be considered additive,
which says one must add an extra pair of parens to specify a single arugment
type that is a tuple:
```swift
let g ((Int, Int)) -> Void = { y in } // y should have type (Int, Int)
```
This patch does not implement that part.
