Add syntax "[#Color(...)#]" for object literals, to be used by
Playgrounds for inline color wells etc. The arguments are forwarded to
the relevant constructor (although we will probably change this soon,
since (colorLiteralRed:... blue:... green:... alpha) is kind of
verbose). Add _ColorLiteralConvertible and _ImageLiteralConvertible
protocols, and link them to the new expressions in the type checker.
CSApply replaces the object literal expressions with a call to the
appropriate protocol witness.
Swift SVN r27479
A non-throwing function can be a trivial subtype of a throwing
function. Encode this rule more directly, introduce some additional
tests to ensure that we get the behavior right where we need exact
matches, and add a failure kind with custom diagnostic for cases where
function types mismatch due to 'throws'.
Swift SVN r27255
Improves the placement of open-existential expressions when accessing
a property or subscript declared in a protocol extension. We need to
delay until the load occurs when the property/subscript has a usable
setter.
Swift SVN r27064
To use members of protocol extensions on existential types, we
introduce an OpenExistentialExpr expression to open up the existential
type (into a local archetype) and perform the operations on that local
archetype.
Unlike with uses of initializers or dynamic-Self-producing
methods of protocols, which produce similar ASTs, we have the type
checker perform the "open" operation and then track it through
constraint application. This scheme is better (because it's more
direct), but it's still using a simplistic approach to deciding where
the actual OpenExistentialExpr goes that needs improvement.
Swift SVN r26964
- Implement SILGen for conditional multi-pattern PBD's.
- Have the type checker check where clauses on PBDs.
- Change the AST to represent complex if/let PBD's with
composed PBDs instead of breaking them down. For example,
represent:
if let x? = foo(), y? = bar() where x == y {
as a single PBD in a StmtCondition instead of representing
it as three entries in the condition.
The later change is good for AST/source fidelity as well as providing
a cheap way to exercise all the logic I'm building.
Swift SVN r26959
This pushes tuple pattern labels forward:
- Actually record them in TuplePatternElt.
- Remove the tuple shuffle ban that prevents some cases
(e.g. the one in the radar) of a tuple with labels being shuffled
onto a tuple without labels.
- Remove dead code enabled by removing the restriction.
Swift SVN r26852
Previously, we were reconstructing this mapping from the "full" opened
type produced by declaration references. However, when dealing with
same-type constraints between associated types and type parameters, we
could end up with an incomplete mapping, which let archetypes slip
through. Most of the churn here is sorting out the locators we need to
use to find the opened-type information. Fixes rdar://problem/18208283
and at least 3 dupes of it that I've found so far.
Swift SVN r25375
John pointed out that messing with the type checker's notion of "subtype"
is a bad idea. Instead, we should just have a separate check for ABI
compatibility...and eventually (rdar://problem/19517003) just insert the
appropriate thunks rather than forcing the user to perform the conversion.
I'm leaving all the tests as they are because I'm adding a post-type-checking
diagnostic in the next commit, and that should pass all the same tests.
Part of rdar://problem/19600325
Swift SVN r25116
Penalize solutions that involve 'as' -> 'as!' changes by recording a Fix
when simplifying the corresponding checked-cast constraint.
<rdar://problem/19724719> Type checker thinks "(optionalNSString ?? nonoptionalNSString) as String" is a forced cast
Swift SVN r25061
These haven't ever been safe in Swift's development because they require
generating thunks, and we currently don't do that. However, we were letting
existential conversions slip through the cracks because we consider them
subtypes, so that /metatype/ conversions work correctly. To be concrete:
"let _: Any.Type = Int.self" is okay.
"let _: (Int) -> Void = { (_: Any) -> Void in return }" is not.
We should implement this some day; that's rdar://problem/19517003.
This produces some lousy error messages, which I intend to fix soon.
Part of rdar://problem/19600325
Swift SVN r24915
- Situations where the type of a return statement's result expression doesn't line up with the function's type annotation.
- Situations where the type of an initializer expression doesn't line up with its declaration's type pattern.
- Situations where we assume a conversion to a built-in protocol must take place, such as in if-statement conditionals.
(Addresses rdar://problem/19224776, rdar://problem/19422107, rdar://problem/19422156, rdar://problem/19547806 and lots of other dupes.)
Swift SVN r24853
Aside from tidying things up, doing this results in some significant benefits:
- Allows for global constraint ordering optimizations over a given expression, not just on a peephole basis.
- Eliminates a set of order-dependent bugs in the solver that have been dogging us for a while. (rdar://problem/19459079)
- Brings another set of tyvar-to-tyvar solving problems out of the realm of the exponential. (rdar://problem/19005271)
- Opens up the possibility of optimizing constraints during later solving phases - not just while generating them.
Swift SVN r24693
Fix diagnostics for 'as' and 'as!' expressions by ensuring that the
conversion constraint used to generate them actually corresponds to the
expression in question. Add tests from 19495142.
Swift SVN r24547
Also, these changes fix the performance regressions that were introduced as a result of September's convertible/init requirement modifications, and allow us to roll back the associated workarounds that were added to the Adventure sample (rdar://problem/18942100).
Swift SVN r24520
Require 'as' when converting from Objective-C type to native type (but
continue to allow implicit conversion from native to Objective-C). This
conversion constraint is called ExplicitConversion; all implicit
conversions are covered by the existing Conversion constraint. Update
standard library and tests to match.
Swift SVN r24496
When dealing with multiple levels of generic parameters, the mapping
from potential archetypes down to actual archetypes did not have
access to the archetypes for outer generic parameters. When same-type
requirements equated a type from the inner generic parameter list with
one from the outer generic parameter list, the reference to the outer
generic parameter list's type would remain dependent. For example,
given:
struct S<A: P> {
init<Q: P where Q.T == A>(_ q: Q) {}
}
we would end up with the dependent type for A (τ_0_0) in the same-type
constraint in the initializer requirement.
Now, notify the ArchetypeBuilder of outer generic signatures (and,
therefore, outer generic parameters), so that it has knowledge of the
mapping from those generic parameters to the corresponding
archetypes. Use that mapping when translating potential archetypes to
real archetypes. Additionally, when a potential archetype is mapped to
a concrete type (via a same-type constraint to a concrete type),
substitute archetypes for any dependent types within the concrete
type.
Remove a bunch of hacks in the compiler that identified dependent
types in "strange" places and tried to map them back to
archetypes. Those hacks handled some narrow cases we saw in the
standard library and some external code, but papered over the
underlying issue and left major gaps.
Sadly, introduce one hack into the type checker to help with the
matching of generic witnesses to generic requirements that follow the
pattern described above. See ConstraintSystem::SelfTypeVar; the proper
implementation for this matching involves substituting the adoptee
type in for Self within the requirement, and synthesizing new
archetypes from the result.
Fixes rdar://18435371, rdar://18803556, rdar://19082500,
rdar://19245317, rdar://19371678 and a half dozen compiler crashers
from the crash suite. There are a few other radars that I suspect this
fixes, but which require more steps to reproduce.
Swift SVN r24460
The archetype opener only needs to perform basic substitutions; let it
do so, avoiding the creation of a pile of type variables that simply
get immediately bound.
Swift SVN r24399
Previously the "as" keyword could either represent coercion or or forced
downcasting. This change separates the two notions. "as" now only means
type conversion, while the new "as!" operator is used to perform forced
downcasting. If a program uses "as" where "as!" is called for, we emit a
diagnostic and fixit.
Internally, this change removes the UnresolvedCheckedCastExpr class, in
favor of directly instantiating CoerceExpr when parsing the "as"
operator, and ForcedCheckedCastExpr when parsing the "as!" operator.
Swift SVN r24253
These changes make the following improvements to how we generate diagnostics for expression typecheck failure:
- Customizing a diagnostic for a specific expression kind is as easy as adding a new method to the FailureDiagnosis class,
and does not require intimate knowledge of the constraint solver’s inner workings.
- As part of this patch, I’ve introduced specialized diagnostics for call, binop, unop, subscript, assignment and inout
expressions, but we can go pretty far with this.
- This also opens up the possibility to customize diagnostics not just for the expression kind, but for the specific types
involved as well.
- For the purpose of presenting accurate type info, partially-specialized subexpressions are individually re-typechecked
free of any contextual types. This allows us to:
- Properly surface subexpression errors.
- Almost completely avoid any type variables in our diagnostics. In cases where they could not be eliminated, we now
substitute in "_".
- More accurately indicate the sources of errors.
- We do a much better job of diagnosing disjunction failures. (So no more nonsensical ‘UInt8’ error messages.)
- We now present reasonable error messages for overload resolution failures, informing the user of partially-matching
parameter lists when possible.
At the very least, these changes address the following bugs:
<rdar://problem/15863738> More information needed in type-checking error messages
<rdar://problem/16306600> QoI: passing a 'let' value as an inout results in an unfriendly diagnostic
<rdar://problem/16449805> Wrong error for struct-to-protocol downcast
<rdar://problem/16699932> improve type checker diagnostic when passing Double to function taking a Float
<rdar://problem/16707914> fatal error: Can't unwrap Optional.None…Optional.swift, line 75 running Master-Detail Swift app built from template
<rdar://problem/16785829> Inout parameter fixit
<rdar://problem/16900438> We shouldn't leak the internal type placeholder
<rdar://problem/16909379> confusing type check diagnostics
<rdar://problem/16951521> Extra arguments to functions result in an unhelpful error
<rdar://problem/16971025> Two Terrible Diagnostics
<rdar://problem/17007804> $T2 in compiler error string
<rdar://problem/17027483> Terrible diagnostic
<rdar://problem/17083239> Mysterious error using find() with Foundation types
<rdar://problem/17149771> Diagnostic for closure with no inferred return value leaks type variables
<rdar://problem/17212371> Swift poorly-worded error message when overload resolution fails on return type
<rdar://problem/17236976> QoI: Swift error for incorrectly typed parameter is confusing/misleading
<rdar://problem/17304200> Wrong error for non-self-conforming protocols
<rdar://problem/17321369> better error message for inout protocols
<rdar://problem/17539380> Swift error seems wrong
<rdar://problem/17559593> Bogus locationless "treating a forced downcast to 'NSData' as optional will never produce 'nil'" warning
<rdar://problem/17567973> 32-bit error message is really far from the mark: error: missing argument for parameter 'withFont' in call
<rdar://problem/17671058> Wrong error message: "Missing argument for parameter 'completion' in call"
<rdar://problem/17704609> Float is not convertible to UInt8
<rdar://problem/17705424> Poor error reporting for passing Doubles to NSColor: extra argument 'red' in call
<rdar://problem/17743603> Swift compiler gives misleading error message in "NSLayoutConstraint.constraintsWithVisualFormat("x", options: 123, metrics: nil, views: views)"
<rdar://problem/17784167> application of operator to generic type results in odd diagnostic
<rdar://problem/17801696> Awful diagnostic trying to construct an Int when .Int is around
<rdar://problem/17863882> cannot convert the expression's type '()' to type 'Seq'
<rdar://problem/17865869> "has different argument names" diagnostic when parameter defaulted-ness differs
<rdar://problem/17937593> Unclear error message for empty array literal without type context
<rdar://problem/17943023> QoI: compiler displays wrong error when a float is provided to a Int16 parameter in init method
<rdar://problem/17951148> Improve error messages for expressions inside if statements by pre-evaluating outside the 'if'
<rdar://problem/18057815> Unhelpful Swift error message
<rdar://problem/18077468> Incorrect argument label for insertSubview(...)
<rdar://problem/18079213> 'T1' is not identical to 'T2' lacks directionality
<rdar://problem/18086470> Confusing Swift error message: error: 'T' is not convertible to 'MirrorDisposition'
<rdar://problem/18098995> QoI: Unhelpful compiler error when leaving off an & on an inout parameter
<rdar://problem/18104379> Terrible error message
<rdar://problem/18121897> unexpected low-level error on assignment to immutable value through array writeback
<rdar://problem/18123596> unexpected error on self. capture inside class method
<rdar://problem/18152074> QoI: Improve diagnostic for type mismatch in dictionary subscripting
<rdar://problem/18242160> There could be a better error message when using [] instead of [:]
<rdar://problem/18242812> 6A1021a : Type variable leaked
<rdar://problem/18331819> Unclear error message when trying to set an element of an array constant (Swift)
<rdar://problem/18414834> Bad diagnostics example
<rdar://problem/18422468> Calculation of constant value yields unexplainable error
<rdar://problem/18427217> Misleading error message makes debugging difficult
<rdar://problem/18439742> Misleading error: "cannot invoke" mentions completely unrelated types as arguments
<rdar://problem/18535804> Wrong compiler error from swift compiler
<rdar://problem/18567914> Xcode 6.1. GM, Swift, assignment from Int64 to NSNumber. Warning shown as problem with UInt8
<rdar://problem/18784027> Negating Int? Yields Float
<rdar://problem/17691565> attempt to modify a 'let' variable with ++ results in typecheck error about @lvalue Float
<rdar://problem/17164001> "++" on let value could give a better error message
Swift SVN r23782
Add the following functionality to the Swift compiler:
* covariant subtyping of Set
* upcasting, downcasting of Set
* automatic bridging between Set and NSSet, including
* NSSet params/return values in ObjC are imported as Set<NSObject>
* Set params/return values in Swift are visible to ObjC as NSSet
<rdar://problem/18853078> Implement Set<T> up and downcasting
Swift SVN r23751
This makes sure we get the same checking for initializer delegation in
structs/enums as we do for classes, fixing rdar://problem/18458622.
Swift SVN r23128
llvm::Optional lives in "llvm/ADT/Optional.h". Like Clang, we can get
Optional in the 'swift' namespace by including "swift/Basic/LLVM.h".
We're now fully switched over to llvm::Optional!
Swift SVN r22477
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 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
When performing name lookup for a declaration that is being called,
use the argument labels at the call site to filter out those
declarations with incompatible argument labels.
Swift SVN r22176
We don't properly open up the existential to make this work, which
leads to an IRGen crash. Reject the uses of generics that would cause
such a crash rdar://problem/17491663.
Swift SVN r21946
t2.swift:3:1: error: argument for generic parameter 'U' could not be
inferred
f(i)
^
t2.swift:2:6: note: in call to function 'f'
func f<T, U>(t: T) -> U? { return nil }
^
Our lack of decent locator information means that we don't get notes
in all of the cases we want them. I'll look at that separately.
Swift SVN r21921
Locators that refer to opened type parameters now carry information
about the source location where we needed to open the type, so that
(for example) we can trace an opened type parameter back to the
location it was opened. As part of this, eliminate the "rootExpr"
fallback, because we're threading constraint locators everywhere.
This is infrastructural, and should be NFC.
Swift SVN r21919
This is another instance where we choose a favored constraint that
only type checks because we're bridging through NSNumber, causing
awful problems. Fixes rdar://problem/17962491.
Swift SVN r21445
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
This is the semantic change we need to eliminate ambiguities when
introducing the new ?? overload. There is a minor regression here with
curried method references, which is covered by <rdar://problem/18006008>.
Swift SVN r21173
While we work out the remaining performance improvements in the type checker, we can improve the user experience for some "runaway solver" bugs by setting a limit on the amount of temporary memory allocated for type variables when solving over a single expression.
Exponential behavior usually manifests itself while recursively attempting bindings over opened type variables in an expression. Each one of these bindings may result in one or more fresh type variables being created. On average, memory consumption by type variables is fairly light, but in some exponential cases it can quickly grow to many hundreds of megabytes or even gigabytes. (This memory is managed by a distinct arena in the AST context, so it's easy to track.) This problem is the source of many of the "freezing" compiler and SourceKit bugs we've been seeing.
These changes set a limit on the amount of memory that can be allocated for type variables while solving for a single expression. If the memory threshold is exceeded, we can surface a type error and suggest that the user decompose the expression into distinct, less-complex sub-expressions.
I've set the current threshold to 15MB which, experimentally, avoids false positives but doesn't let things carry on so long that the user feels compelled to kill the process before they can see an error message. (As a point of comparison, the largest allocation of type variable data while solving for a single expression in the standard library is 592,472 bytes.) I've also added a new hidden front-end flag, "solver-memory-threshold", that will allow users to set their own limit, in bytes.
Swift SVN r20986
Rather than just saying "'Foo' is not constructible with '()'", say
"'Foo' cannot be constructed because it has no accessible initializers",
which would help framework authors realize what they did wrong.
<rdar://problem/17717714>
Swift SVN r20232
Create a new "OptionalObject" constraint kind in the solver that relates an optional type to its payload type, preserving lvalue-ness, and use it to model ForceValueExpr under the optional-lvalues regime.
Swift SVN r20140
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
When we see a '.member' expression in optional context, look for the member in the optional's object type if it isn't found in Optional itself. <rdar://problem/16125392>
Swift SVN r19469
