[SR-10689] DataProtocol.firstRange/lastRange does not work properly

[swift-ci]

Previous ID	SR-10689
Radar	rdar://79092495
Original Reporter	nanasi (JIRA User)
Type	Bug
Status	Resolved
Resolution	Done

Environment

Xcode 10.2

Apple Swift version 5.0 (swiftlang-1001.0.69.5 clang-1001.0.46.3)
Target: x86_64-apple-darwin18.5.0

Additional Detail from JIRA

Votes	0
Component/s	Foundation
Labels	Bug
Assignee	@YOCKOW
Priority	Medium

md5: 9dd008936346109659158a2dac5cae0c

is duplicated by:

• SR-14792 Linux: Segmentation Fault with Data's lastRangeOf

Issue Description:

case 1

import Foundation

let data = Data([1, 2, 3])
print(data.range(of: Data([1, 2, 3])))       // print 0..<3
print(data.firstRange(of: Data([1, 2, 3])))  // print nil

case 2

import Foundation

let data = Data([1, 2, 3])
let range = data.startIndex..<data.endIndex
print(data.range(of: Data([1]), options: .backwards, in: range))  // print 0..<1
print(data.lastRange(of: Data([1]), in: range))                   // causes EXC_BAD_INSTRUCTION

case 2 console:

error: Execution was interrupted, reason: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0).
The process has been left at the point where it was interrupted, use "thread return -x" to return to the state before expression evaluation.

* thread #​1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
  * frame #​0: 0x000000011b7092ad libswiftFoundation.dylib`Foundation.Data.subscript.read : (Swift.Int) -> Swift.UInt8 + 317
    frame #​1: 0x00000001052d5117 libswiftCore.dylib`dispatch thunk of Swift.Collection.subscript.read : (A.Index) -> A.Element + 7
    frame #&#8203;2: 0x000000011b6f9d5f libswiftFoundation.dylib`(extension in Foundation):Foundation.DataProtocol.lastRange<A, B where A1: Foundation.DataProtocol, B1: Swift.RangeExpression, A.Index == B1.Bound>(of: A1, in: B1) -> Swift.Optional<Swift.Range<A.Index>> + 1279
    frame #&#8203;3: 0x00000001220a3662 $__lldb_expr38`main at Untitled Page 2.xcplaygroundpage:12:12
    frame #&#8203;4: 0x0000000104f9b620 MyPlayground3`linkResources + 304
    frame #&#8203;5: 0x0000000106e50aec CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
    frame #&#8203;6: 0x0000000106e502b0 CoreFoundation`__CFRunLoopDoBlocks + 336
    frame #&#8203;7: 0x0000000106e4ab34 CoreFoundation`__CFRunLoopRun + 1252
    frame #&#8203;8: 0x0000000106e4a302 CoreFoundation`CFRunLoopRunSpecific + 626
    frame #&#8203;9: 0x000000010ecfe2fe GraphicsServices`GSEventRunModal + 65
    frame #&#8203;10: 0x000000010b017ba2 UIKitCore`UIApplicationMain + 140
    frame #&#8203;11: 0x0000000104f9b6ed MyPlayground3`main + 205
    frame #&#8203;12: 0x00000001087bd541 libdyld.dylib`start + 1
    frame #&#8203;13: 0x00000001087bd541 libdyld.dylib`start + 1

and `lastRange(of: )` returns `firstRange(of:in: )` on master branch currently.
https://github.com/apple/swift-corelibs-foundation/blob/8043670b9d991d45ca72cfadc3806c68e9e16a05/Foundation/DataProtocol.swift#L82-L84

[YOCKOW]

Opened PR#2499: #2499

[YOCKOW]

PR for SDK Overlay: swiftlang/swift#28639

[CodaFi]

@swift-ci create

[CodaFi]

Re-upping the radar here since the original only tracked getting this fixed on Darwin.

[mickeyl]

Is this fixed in the meantime? I have just opened https://bugs.swift.org/browse/SR-14792, which is a duplicate of this very bug.

Needless to say that I'm somewhat shocked that such a basic functionality is still broken on Linux… so much for attempting to cover more than Apple's platforms.

[YOCKOW]

@mickeyl

#2499 was merged into main 5 days ago. So this issue is fixed. I'm closing this.