This commit modifies Sema to add type checking for potentially unavailable
method references. We now record the reason for method unavailability when
recording a potential overload choice during member constraint simplification
and either diagnose or lift to an optional type during CSApply. This commit also
generalizes UnavailableToOptionalExpr to take an arbitrary subexpression.
This commit does not address potentially unavailable properties, initializers,
or dynamic member references.
Swift SVN r22508
This commit adds tracking of the reason a declaration reference is potentially
unavailable to the UnavailableToOptionalExpr AST node and to OverloadChoice. We
will use this reason during SILGen to emit the appropriate run-time check and
during typechecking to provide more helpful diagnostics.
To keep OverloadChoice as small as possible, we encode the reason as an index
into a vector of reasons stored in a given instance of ConstraintSystem (this is
the same approach that Fix takes).
This commit adds Sema/OverloadChoice.cpp (for the parts of OverloadChoice that
now rely on ConstraintSystem) and AST/Availability.h (to bring in
availability-related structures without TypeRefinementContext).
Swift SVN r22377
This patch adds SILGen for the API availability (#os(...)) construct. To do so,
it (1) adds version range information to the AvailabilityQueryExpr AST in Sema,
during type refinement context construction; and (2) uses that version range,
during SILGen, to emit a call to the standard library's
_stdlib_isOSVersionAtLeast function.
Swift SVN r22348
There are a lot of different ways to interpret the
"kind" of an access. This enum specifically dictates
the semantic rules for an access: direct-to-storage
and direct-to-accessor accesses may be semantically
different from ordinary accesses, e.g. if there are
observers or overrides.
Swift SVN r22290
This patch adds the ability (-enable-experimental-unavailable-as-optional) to
treat potentially unavailable declarations as if they had optional types. For
the moment, this is only implemented for global variables.
The high-level approach is to (1) record the potential unavailability of a
declaration reference in the overload choice during constraint generation; (2)
treat the declaration as if it had an optional type during overload resolution
(this is similar to how optional protocol members are treated); and (3) add an
implicit conversion (UnavailableToOptionalExpr) during constraint application
to represent the run-time availability check and optional injection.
This patch does not implement SILGen for UnavailableToOptionalExpr.
Swift SVN r22245
This patch extends the AST and parsing of #os(...) queries to permit queries for
multiple platforms, e.g., #os(OSX >= 10.10, iOS >= 8.0). It also improves
parsing error recovery.
Swift SVN r22154
This commit adds a new expression (AvailabilityQueryExpr) and a single kind of
specification for when a block of code or function is available
(VersionConstraintAvailabilitySpec). We may add more kinds of specifications
in the future. At the moment, the AvailabilityQueryExpr allows only a
single platform to be queried; I will add support for multiple platforms
in a later commit.
This commit contains just the added AST nodes; no parsing, type checking, etc.
I’ve added assert(false && “Unimplemented”) for places where support for
AvailabilityQueryExpr will need to be added later.
Swift SVN r21760
If either parameter to == has a known concrete type at constraint generation
time, see if that type is a nominal that can derive its conformance to
Equatable. If so, do so, and then add that == to the overload set.
(It may already be there, but that's okay -- it will get uniqued later.)
This isn't perfect because it relies on one of the parameters to == having
a concrete type /before/ constraint solving. There are plenty of reasons
why that wouldn't happen. But this at least fixes the common case, and
breaking the expression up into multiple lines is a less distasteful
workaround than replacing (x == .Value) with !(x != .Value). I've added a
test case that should work but doesn't that we can revisit later.
rdar://problem/18073705
Swift SVN r21557
Introduce an attribute that describes when a given CF type is
toll-free-bridged to an Objective-C class, and which class that
is. Use that information in the type checker to provide the CF <->
Objective-C toll-free-bridged conversions directly, rather than using
the user-defined conversion machinery.
Swift SVN r21376
This allows UnicodeScalars to be constructed from an integer, rather
then from a string. Not only this avoids an unnecessary memory
allocation (!) when creating a UnicodeScalar, this also allows the
compiler to statically check that the string contains a single scalar
value (in the same way the compiler checks that Character contains only
a single extended grapheme cluster).
rdar://17966622
Swift SVN r21198
A checked cast such as "x as String" or "x as? [String]", where x is of
class or Objective-C existential type, is now handled as a normal
checked cast rather than a Sema-generated call to the corresponding
witness. This eliminates a pile of hairy code from constraint
application and takes a step toward <rdar://problem/17408934>.
The part of the switch_objc.swift test I removed wasn't testing
anything useful; that's what <rdar://problem/17408934> is about.
Swift SVN r20970
Introduce the new BooleanLiteralConvertible protocol for Boolean
literals. Take "true" and "false" as real keywords (which is most of the
reason for the testsuite churn). Make Bool BooleanLiteralConvertible
and the default Boolean literal type, and ObjCBool
BooleanLiteralConvertible. Fixes <rdar://problem/17405310> and the
recent regression that made ObjCBool not work with true/false.
Swift SVN r19728
- Change the parser to accept "objc" without an @ sign as a contextual
keyword, including the dance to handle the general parenthesized case.
- Update all comments to refer to "objc" instead of "@objc".
- Update all diagnostics accordingly.
- Update all tests that fail due to the diagnostics change.
- Switch the stdlib to use the new syntax.
This does not switch all tests to use the new syntax, nor does it warn about
the old syntax yet. That will be forthcoming. Also, this needs a bit of
refactoring, which will be coming up.
Swift SVN r19555
We no longer need this language feature. The Sema support is still skeletally kept in place because removing it seems to totally break pointer conversions; I need to work with Joe and Doug to figure out why that's the case.
Swift SVN r19289
Add primitive type-checker rules for pointer arguments. An UnsafePointer argument accepts:
- an UnsafePointer value of matching element type, or of any type if the argument is UnsafePointer<Void>,
- an inout parameter of matching element type, or of any type if the argument is UnsafePointer<Void>, or
- an inout Array parameter of matching element type, or of any type if the argument is UnsafePointer<Void>.
A ConstUnsafePointer argument accepts:
- an UnsafePointer, ConstUnsafePointer, or AutoreleasingUnsafePointer value of matching element type, or of any type if the argument is ConstUnsafePointer<Void>,
- an inout parameter of matching element type, or of any type if the argument is ConstUnsafePointer<Void>, or
- an inout or non-inout Array parameter of matching element type, or of any type if the argument is ConstUnsafePointer<Void>.
An AutoreleasingUnsafePointer argument accepts:
- an AutoreleasingUnsafePointer value of matching element type, or
- an inout parameter of matching element type.
This disrupts some error messages in unrelated tests, which is tracked by <rdar://problem/17380520>.
Swift SVN r19008
This means that we'll get deferred checking of array and dictionary
downcasts when writing "arr as Derived[]",
"(dict as? Dictionary<DerivedKey, DerivedValue>)!", etc, when the
collection can do so.
This is both a general optimization and also staging for
<rdar://problem/17319154>.
Swift SVN r18975
This is all goodness, and eliminates a major source of implicit conversions.
One thing this regresses on though, is that we now reject "x == nil" where
x is an option type and the element of the optional is not Equtatable. If
this is important, there are ways to enable this, but directly testing it as
a logic value is more straight-forward.
This does not include support for pattern matching against nil, that will be
a follow on patch.
Swift SVN r18918
Semantically, these expressions handle the same thing: an upcast of a
collection when the underlying element types of the source are
subtypes of or can be bridged to subtypes of the destination. This
reduces some branching in the type checker and eliminates duplication
in SILGen.
Swift SVN r18865
Allow class metatypes (including class-constrained existential metatypes) to be treated as subtypes of AnyObject, and single-@objc protocol metatypes to be treated as subtypes of the Protocol class from objc. No codegen support yet, so this is hidden behind a frontend flag for now.
Swift SVN r18810
Tweak the AST representation and type-checking of default arguments to preserve a full ConcreteDeclRef with substitutions to the owner of the default arguments. In SILGen, emit default argument generators with the same genericity as the original function.
Swift SVN r18760
There's a bit of a reshuffle of the ExplicitCastExpr subclasses:
- The existing ConditionalCheckedCastExpr expression node now represents
"as?".
- A new ForcedCheckedCastExpr node represents "as" when it is a
downcast.
- CoerceExpr represents "as" when it is a coercion.
- A new UnresolvedCheckedCastExpr node describes "as" before it has
been type-checked down to ForcedCheckedCastExpr or CoerceExpr. This
wasn't a strictly necessary change, but it helps us detangle what's
going on.
There are a few new diagnostics to help users avoid getting bitten by
as/as? mistakes:
- Custom errors when a forced downcast (as) is used as the operand
of postfix '!' or '?', with Fix-Its to remove the '!' or make the
downcast conditional (with as?), respectively.
- A warning when a forced downcast is injected into an optional,
with a suggestion to use a conditional downcast.
- A new error when the postfix '!' is used for a contextual
downcast, with a Fix-It to replace it with "as T" with the
contextual type T.
Lots of test updates, none of which felt like regressions. The new
tests are in test/expr/cast/optionals.swift.
Addresses <rdar://problem/17000058>
Swift SVN r18556
This bans the syntax
x as T!
because the user probably wanted "(x as T)!", but the parsing makes
more sense as "x as (T!)". When complaining about this syntax, provide
notes with Fix-Its for both parenthesizations, and recover as if the
user took the first one, which is by far more common.
Addresses <rdar://problem/16952768>.
Swift SVN r18435
This allows us to cast an AnyObject (or optional thereof) down to a
specific array, e.g.,
if let strArr = obj as String[] { ... }
Addresses most of <rdar://problem/16952771>.
Swift SVN r18397
Array downcast is an explicit cast written "x as U[]", not an implicit
conversion, so make it a subclass of ExplicitCastExpr. The only
effective change here is that we retain the location of the "as" and
the type as written in the AST. No semantic change.
Swift SVN r18391
upcasts."
Reinstate "Restrict the array-bridged conversion to non-verbatim
bridging."
Reinstate "[stdlib] Fix T[].bridgeFromObjectiveC"
Reinstate "[stdlib] Fix T[].bridgeFromObjectiveC"
Reinstate "[stdlib] Move _arrayBridgedDownCast to Foundation"
Reinstate "Replace "can" with "cannot" in a message."
Reinstate "Implement support for non-verbatim T[] -> AnyObject[]
upcasts."
This reinstates commit r18291.
This reinstates commit r18290.
This reinstates commit r18288.
This reinstates commit r18287.
This reinstates commit r18286.
This reinstates commit r18293.
This reinstates commit r18283.
John fixed the issue in r18294.
Swift SVN r18299
Revert "Restrict the array-bridged conversion to non-verbatim bridging."
Revert "[stdlib] Fix T[].bridgeFromObjectiveC"
Revert "[stdlib] Fix T[].bridgeFromObjectiveC"
Revert "[stdlib] Move _arrayBridgedDownCast to Foundation"
Revert "Replace "can" with "cannot" in a message."
Revert "Implement support for non-verbatim T[] -> AnyObject[] upcasts."
This reverts commit r18291.
This reverts commit r18290.
This reverts commit r18288.
This reverts commit r18287.
This reverts commit r18286.
This reverts commit r18293.
This reverts commit r18283.
Sorry for the number of reverts, but I needed to do this many to get a clean
revert to r18283.
Swift SVN r18296
One of my recent type-checker changes starting passing all array
upcasts, including "bridged" ones like String[] -> AnyObject[],
through the library entry point _arrayUpCast, which is only meant for
class/ObjC existential types that are bridged verbatim.
Fixes part of <rdar://problem/16952238>; more cleanup to follow.
Swift SVN r18283
