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
We need to admit a potential inout-to-pointer conversion even if the inout references an array, because we can have pointers to arrays. Add a short-circuit so that array-to-pointer conversions always beat inout-to-pointer conversions; both solutions could otherwise be considered valid for an UnsafePointer<Void>, and passing a pointer to the array reference rather than to the array data would be very bad.
Swift SVN r19270
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
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
One difficulty in generating reasonable diagnostic data for type check failures has been the fact that many constraints had been synthesized without regard for where they were rooted in the program source. The result of this was that even though we would store failure information for specific constraints, we wouldn't emit it for lack of a source location. By making location data a non-optional component of constraints, we can begin diagnosing type check errors closer to their point of failure.
Swift SVN r18751
We removed this feature when we changed casting syntax, but left it in
the type checker to help migrate code via a Fix-It. We no longer need
it.
Swift SVN r18729
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
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
Previously, we were relying on overly-general subtyping to determine
when we could perform an array upcast, which pushed some non-verbatim
bridging through that path. Instead, restrict array upcasts to classes
and ObjC existentials, and use bridging casts for the other cases.
Swift SVN r18291
- Continue adding support for checked downcasts of array types (rdar://problem/16535104)
- Fix non-bridged array conversions post-r17868
- Fix rdar://problem/16773693
- Add tests for NSArray coercions to and from Array<T>
Swift SVN r17957
This is fairly ugly, because we're halfway between a-function-type-takes-a-tuple and a-function-type-takes-a-set-of-parameters. However, it's another step toward -strict-keyword-arguments.
Swift SVN r17727
Introduce a new locator kind for argument/parameter comparisons that
tracks both the argument and the parameter, which we will eventually
use in diagnostics more regularly. For now, this helps us smooth over
scalar-to-tuple/tuple-to-tuple/tuple-to-scalar nonsense when dealing
with calls.
Fix a pile of fallout from this change.
Swift SVN r17648
We're going to want to re-use the argument/parameter matching of
matchCallArguments() elsewhere, so separate it from the constraint system.
Swift SVN r17626
Rather than force conformances to Equatable to be added to all imported enumeration types outright, change them back to being lazily added. We can then handle situations where new overloads of '==' are introduced during constraint generation by re-writing the relevant overload disjunction constraint to include the newly forced declarations as bind options.
Swift SVN r17557
Previously, we were just using the base name, which resulted in massive
inefficiency when dealing with Clang (we basically had to check every
selector in the system to see if it had the same first selector piece).
I've hacked ConstraintSystem a bit to carry a map from UnresolvedDotExpr
to the ApplyExpr that consumes it, so that we can use the full DeclName
and look up methods by full selector.
Now that dynamic lookup is fast, re-enable it for the
Foundation_bridge.swift test. (r17520 actually provided most of the benefit.)
This does break selector lookup on AnyObject when doing selector splitting,
and slightly regresses diagnostics when you try to call a method on AnyObject
and forget a parameter name.
<rdar://problem/16808651>. Part of the Playground performance efforts.
Swift SVN r17524
Implement a completely new path for matching up an argument tuple to a
parameter tuple, which handles the specific rules we want for
calls. The rules are:
- The keyword arguments at the call site must match those of the
declaration; one cannot omit a keyword argument if the declaration
requires it, nor can one provide a keyword argument if the
declaration doesn't have one.
- Arguments must be passed in order, except that arguments for
parameters with defaults can be re-ordered among themselves (we
can't test all of this because neither constraint application nor
the AST can express these).
QoI is extremely important in this area, and this change improves the
situation considerably. We now provide good diagnostics for several
important cases, with Fix-Its to clean up the code:
- Missing keyword arguments:
t.swift:8:13: error: missing argument labels 'x:y:' in call
allkeywords1(1, 2)
^
x: y:
- Extraneous keyword arguments:
t.swift:17:12: error: extraneous argument labels 'x:y:' in call
nokeywords1(x: 1, y: 1)
^~~~ ~~~
- General confusion over keyword arguments (some missing, some
wrong, etc.):
t.swift:26:14: error: incorrect argument labels in call (have
'x:_:z:', expected '_:y:z:')
somekeywords1(x: 1, 2, z: 3)
^~~~
y:
There are still a few areas where the keyword-argument-related
diagnostics are awful, which correspond to FIXMEs in this
implementation:
- Duplicated arguments: f(x: 1, x: 2)
- Extraneous arguments: f(x: 1, y: 2, z: 3) where f takes only 2
parameters
- Missing arguments
- Arguments that are out-of-order
- Proper matching of arguments to parameters for diagnostics that
complain about type errors.
And, of course, since this has only been lightly tested, there are
undoubtedly other issues lurking.
This new checking is somewhat disjoint from what constraint
application can handle, so we can type-check some things that will
then fail catastrophically at constraint application time. That work
is still to come, as is the AST work to actually represent everything
we intend to allow.
This is part of <rdar://problem/14462349>.
Swift SVN r17341
Another baby step toward <rdar://problem/14462349>, made even more
tepid by the fact that I've quarantined this behind a new flag,
-strict-keyword-arguments. Enforcing this breaks a lot of code, so I'd
like to bring up the new model on the side (with good diagnostics that
include Fix-Its) before trolling through the entire standard library
and testsuite to fix violations of these new rules.
Swift SVN r17143
This is the simplest case to test the infrastructure for
adding/removing/fixing keyword arguments at the call site that don't
line up with the keyword arguments in a declaration. Baby steps toward
<rdar://problem/14462349>.
Swift SVN r17136
