[SR-5209] Searching a Data slice with default range results in a crash

[CharlesJS]

Previous ID	SR-5209
Radar	rdar://problem/36261057
Original Reporter	@CharlesJS
Type	Bug

Additional Detail from JIRA

Votes	2
Component/s	Foundation
Labels	Bug
Assignee	None
Priority	Medium

md5: f61c821c7374601c9542542c2b5e3bfb

Issue Description:

When searching a Data object that is a slice of another Data object, the default value for the 'range' parameter becomes the bounds of the parent data, rather than the slice. This results in a crash when trying to search using range(of:), as you can see by running the code below:

import Foundation

let data = "FooBar".data(using: .ascii)!
let slice = data[3...] // Bar

let range = slice.range(of: "a".data(using: .ascii)!) // Crash! NSRangeException: range {0, 6} exceeds data length 3

[belkadan]

cc @phausler

[karwa]

+1, still occurs in Swift 4.0.3

import Foundation
let dataOne = Data(0..<100)
let dataTwo = Data(25..<30)
dataOne.range(of: dataTwo) // returns: .some(25..<30)
dataOne.subdata(in: 10..<90).range(of: dataTwo) // returns: .some(15..<20)
dataOne[10..<90].range(of: dataTwo) // CRASH!

[belkadan]

@swift-ci create