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Eager array bridging #5488

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Eager array bridging #5488

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f5a139b
[stdlib] Better diagnostics for unsafeDowncast
Aug 13, 2016
2392786
[stdlib] Add a default argument for convenience
Aug 13, 2016
f8c5a12
[stdlib] Stop using ArrayBuffer
Oct 26, 2016
4ab8be9
[stdlib] Rip out ArrayBuffer
Aug 13, 2016
21c31ef
[stdlib] Drop test
Aug 25, 2016
a54806e
XFAIL tests that depend on stdlib implementation details
Aug 25, 2016
53fa261
Rename some test helpers so tests make sense.
Aug 25, 2016
c71593a
Modernize some test code
Aug 26, 2016
daff309
XFAIL tests I don't know how to fix
Aug 26, 2016
5448707
fix reflections tests
Nov 14, 2016
ae33082
unxfail a test that is now passing
Nov 14, 2016
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19 changes: 6 additions & 13 deletions stdlib/public/SDK/Foundation/NSArray.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -33,19 +33,12 @@ extension Array : _ObjectiveCBridgeable {
internal init(_cocoaArray: NSArray) {
_sanityCheck(_isBridgedVerbatimToObjectiveC(Element.self),
"Array can be backed by NSArray only when the element type can be bridged verbatim to Objective-C")
// FIXME: We would like to call CFArrayCreateCopy() to avoid doing an
// objc_msgSend() for instances of CoreFoundation types. We can't do that
// today because CFArrayCreateCopy() copies array contents unconditionally,
// resulting in O(n) copies even for immutable arrays.
//
// <rdar://problem/19773555> CFArrayCreateCopy() is >10x slower than
// -[NSArray copyWithZone:]
//
// The bug is fixed in: OS X 10.11.0, iOS 9.0, all versions of tvOS
// and watchOS.
self = Array(
_immutableCocoaArray:
unsafeBitCast(_cocoaArray.copy() as AnyObject, to: _NSArrayCore.self))
self.init()
let n = _cocoaArray.count
self.reserveCapacity(n)
for i in 0..<n {
append(_cocoaArray.object(at: i) as! Element)
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This has n objc_msgSends, perhaps we should thunk out for getObjects:range: here to just have a C function callout and a single objc msg send.

that way you would send a UnsafeMutablePointer<Unmanaged<NSObject>> across to be populated and iterate in swift with taking the unretained value back out of the buffer

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Isn't this the kind of thing that NSFastEnumeration was designed to do?

}
}

@_semantics("convertToObjectiveC")
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