In UTF-8 decoder:
- implement U+FFFD insertion according to the recommendation given in the
Unicode spec. This required changing the decoder to become stateful, which
significantly increased complexity due to the need to maintain an internal
buffer.
- reject invalid code unit sequences properly instead of crashing rdar://16767868
- reject overlong sequences rdar://16767911
In stdlib:
- change APIs that assume that UTF decoding can never fail to account for
possibility of errors
- fix a bug in UnicodeScalarView that could cause a crash during backward
iteration if U+8000 is present in the string
- allow noncharacters in UnicodeScalar. They are explicitly allowed in the
definition of "Unicode scalar" in the specification. Disallowing noncharacters
in UnicodeScalar prevents actually using these scalar values as internal
special values during string processing, which is exactly the reason why they
are reserved in the first place.
- fix a crash in String.fromCString() that could happen if it was passed a null
pointer
In Lexer:
- allow noncharacters in string literals. These Unicode scalar values are not
allowed to be exchanged externally, but it is totally reasonable to have them
in literals as long as they don't escape the program. For example, using
U+FFFF as a delimiter and then calling str.split("\uffff") is completely
reasonable.
This is a lot of changes in a single commit; the primary reason why they are
lumped together is the need to change stdlib APIs to account for the
possibility of UTF decoding failure, and this has long-reaching effects
throughout stdlib where these APIs are used.
Swift SVN r19045
This entry point is used in conditional downcasts (as?) to attempt to
bridge from an Objective-C class down to a specific native type (e.g.,
array, dictionary), bridging all elements eagerly so that it can
produce nil if the bridging would fail.
This is the scaffolding for <rdar://problem/17319154>, and makes the
example there work, but there is much more cleanup and optimization to
do.
Swift SVN r18999
These types are often useless and confusing to users who expect to be able to use Sequence or Generator as types in their own right like in C# or Java. While we're here, relax the rules for self-conformance to admit methods returning 'Self'. Covariant return types should not actually prevent a protocol type from conforming to itself, and the stdlib makes particular use of protocols with 'init' requirements which implicitly return Self.
Swift SVN r18989
This makes categories of NSString, NSArray, and NSDictionary available
on String, Array, and Dictionary. Note that we only consider
categories not present in the Objective-C Foundation module, because
we want to manually map those APIs ourselves. Hence, no changes to the
NSStringAPI. Implements <rdar://problem/13653329>.
Swift SVN r18920
In modern ObjC Protocol's object-ness is vestigial, and its class object isn't even visible from newer runtimes, so we can't use it as type metadata. Import it as a foreign class so that we make our own artificial metadata. Fixes <rdar://problem/17303759>.
Swift SVN r18882
...because we decided to change the selector for our own nefarious purposes.
Extending our UIActionSheet hack, take 3. <rdar://problem/17012323>
Swift SVN r18881
<rdar://problem/17303759> -- we need to do something special for the Protocol type's metadata, because its ObjC class object is hidden.
Swift SVN r18871
Previously, we were only changing whether the object was of the right
type, and not performing a deep check that (for example) the
underlying array contained NSStrings for an "is String[]". Fixes the
rest of <rdar://problem/16972956>.
Swift SVN r18728
Rather than only allowing downcasting from AnyObject, allow it for any
class or Objective-C existential type, e.g., "NSArray() as
Int[]". While here, reduce our reliance on implicit conversions when
checking bridging. This is most of <rdar://problem/16972956>, but 'is'
still doesn't work properly in these cases.
Swift SVN r18693
The CALayer brittleness in <rdar://problem/17014037> is worse than we thought—we can't r/r *at all* before super.init. Go through some contortions to ensure that, when doing direct stored property access in an initializer, we always base off of a +0 value. I tried fixing this in a more general and principled way using SGFContext::AllowPlusZero, but that introduced miscompiles we don't have the luxury of tracking down right now, so hack a more targeted fix that only affects class initializers.
Swift SVN r18635
CALayer and potentially other framework classes implement their own refcounting
schemes that assume [self retainCount] == 1 at initialization time, a guarantee
SILGen didn't attempt to meet until now. Set a flag in SILGenFunction while
doing initializer delegations to indicate that a 'self' reference can consume
the current 'self' binding, and reinitialize rather than reassign 'self' with
the result of the delegation if it was successfully consumed. Fixes
<rdar://problem/17014037>.
Swift SVN r18608
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
Blocks need their own type metadata with value witnesses appropriate to the block representation. Fixes <rdar://problem/16918740> and <rdar://problem/16981126>.
Swift SVN r18508
- rdar://problem/16776273, wherein conversions between nil and .None were permitted
due to an implicit conversion between nil and COpaquePointer.
- rdar://problem/16877526, where we needed to add new equality overloads to handle
conversions between nil and .None given the supression of user conversions.
(Thanks to Ted for the overloads and test.)
Swift SVN r18473
Previously, we were relying on user-defined conversions to perform the
final bridging from the Objective-C class type (e.g., NSString) to its
Swift value type (String). That works for NSString <-> String, but not
for arbitrary arrays. Use the bridgeFromObjectiveC() witness instead,
so we can handle:
let obj: AnyObject = ...
let strArr: String[] = obj!
Fixes <rdar://problem/16952771>.
Swift SVN r18422
This makes fun bridging like
var obj: AnyObject! = [3.14159, 2.71828, 0] as Double[]
if let intArr = obj as Int[] {
println("Array of doubles as ints is \(intArr)")
}
"work", given that NSNumber is the common class type through which we
are bridging.
Swift SVN r18398
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
Unfortunately, we can't add an implicit conversion from
String to CFString, or anything analogous like string
literal support, without introducing ambiguities
when converting to AnyObject.
rdar://16271682
Swift SVN r18387
The "is" expression itself isn't really able to cope with optionals
well itself, so in the hard cases we'll defer to a conditional checked
cast and then check whether the resulting optional is non-empty. Fixes
the rest of <rdar://problem/16953860>.
Swift SVN r18361
Checked casting handles multiple levels of optionality properly
already, and does so by binding rather than forcing. Fixes the
immediate issue in <rdar://problem/16953860>.
Swift SVN r18351
This allows us to cast "through" a bridged class type in an "as" case,
e.g.,
if let str = obj as String { ... }
where obj is an AnyObject (or optional/implicitly unwrapped optional
thereof). In such cases, we perform a checked cast to the
corresponding class type (NSString in this case) and then convert the
(optional!) result down to the value type.
Addresses the main part of <rdar://problem/15288553>, but we still
have trouble with "is" with optionals, and the #if false'd out
testcase incorrectly fails due to <rdar://problem/16953860>.
Swift SVN r18347
We weren't diagnosing initializer delegation/chaining, subscripts, or
(the one that got me concerned) members accessed through AnyObject.
Swift SVN r18271
Use this for -class and +class, to make them less ad hoc. More to follow.
As part of this, actually mark imported unavailable declarations in a
protocol as "optional", because nobody should have to implement an
unavailable declaration.
Swift SVN r18262
assert() and fatalError()
These functions are meant to be used in user code. They are enabled in debug
mode and disabled in release or fast mode.
_precondition() and _preconditionFailure()
These functions are meant to be used in library code to check preconditions at
the api boundry. They are enabled in debug mode (with a verbose message) and
release mode (trap). In fast mode they are disabled.
_debugPrecondition() and _debugPreconditionFailure()
These functions are meant to be used in library code to check preconditions that
are not neccesarily comprehensive for safety (UnsafePointer can be null or an
invalid pointer but we can't check both). They are enabled only in debug mode.
_sanityCheck() and _fatalError()
These are meant to be used for internal consistency checks. They are only
enabled when the library is build with -DSWIFT_STDLIB_INTERNAL_CHECKS=ON.
I modified the code in the standard library to the best of my judgement.
rdar://16477198
Swift SVN r18212