[stdlib][WIP] Eliminate (Closed)CountableRange using conditional conformance (#13342)

* Make Range conditionally a Collection

* Convert ClosedRange to conditionally a collection

* De-gyb Range/ClosedRange, refactoring some methods.

* Remove use of Countable{Closed}Range from stdlib

* Remove Countable use from Foundation

* Fix test errors and warnings resulting from Range/CountableRange collapse

* fix prespecialize test for new mangling

* Update CoreAudio use of CountableRange

* Update SwiftSyntax use of CountableRange

* Restore ClosedRange.Index: Hashable conformance

* Move fixed typechecker slowness test for array-of-ranges from slow to fast, yay

* Apply Doug's patch to loosen test to just check for error

Author: airspeedswift

stdlib/private/StdlibCollectionUnittest/CheckCollectionType.swift.gyb

@@ -1556,7 +1556,7 @@ extension TestSuite {
       return
     }
 
-    func toCollection(_ r: CountableRange<Int>) -> C {
+    func toCollection(_ r: Range<Int>) -> C {
       return makeCollection(r.map { wrapValue(OpaqueValue($0)) })
     }
 

stdlib/private/StdlibCollectionUnittest/MinimalCollections.swift.gyb

@@ -160,7 +160,7 @@ internal enum _CollectionOperation : Equatable {
     case .reserveCapacity:
       let invalidIndices = newElementsIds.indices
       newElementsIds.replaceSubrange(
-        Range(invalidIndices),
+        invalidIndices,
         with: repeatElement(nextStateId, count: invalidIndices.count))
       newEndIndexId = nextStateId
 
@@ -180,7 +180,7 @@ internal enum _CollectionOperation : Equatable {
 
       let invalidIndices = subRange.lowerBound..<newElementsIds.endIndex
       newElementsIds.replaceSubrange(
-        Range(invalidIndices),
+        invalidIndices,
         with: repeatElement(nextStateId, count: invalidIndices.count))
       newEndIndexId = nextStateId
 
@@ -189,7 +189,7 @@ internal enum _CollectionOperation : Equatable {
 
       let invalidIndices = atIndex..<newElementsIds.endIndex
       newElementsIds.replaceSubrange(
-        Range(invalidIndices),
+        invalidIndices,
         with: repeatElement(nextStateId, count: invalidIndices.count))
       newEndIndexId = nextStateId
 
@@ -200,7 +200,7 @@ internal enum _CollectionOperation : Equatable {
 
       let invalidIndices = atIndex..<newElementsIds.endIndex
       newElementsIds.replaceSubrange(
-        Range(invalidIndices),
+        invalidIndices,
         with: repeatElement(nextStateId, count: invalidIndices.count))
       newEndIndexId = nextStateId
 
@@ -209,7 +209,7 @@ internal enum _CollectionOperation : Equatable {
 
       let invalidIndices = index..<newElementsIds.endIndex
       newElementsIds.replaceSubrange(
-        Range(invalidIndices),
+        invalidIndices,
         with: repeatElement(nextStateId, count: invalidIndices.count))
       newEndIndexId = nextStateId
 
@@ -222,7 +222,7 @@ internal enum _CollectionOperation : Equatable {
 
       let invalidIndices = subRange.lowerBound..<newElementsIds.endIndex
       newElementsIds.replaceSubrange(
-        Range(invalidIndices),
+        invalidIndices,
         with: repeatElement(nextStateId, count: invalidIndices.count))
       newEndIndexId = nextStateId
 
@@ -592,7 +592,7 @@ public struct ${Self}<T> : ${SelfProtocols} {
   }
 
 %     if StrideableIndex:
-  public typealias Indices = CountableRange<${Index}>
+  public typealias Indices = Range<${Index}>
 %     elif Traversal == 'RandomAccess':
   // FIXME: this shouldn't be necessary, should come by default
   public typealias Indices = DefaultIndices<${Self}<T>>
@@ -866,7 +866,7 @@ public struct ${Self}<Element> : ${SelfProtocols} {
   public typealias Index = ${Index}
 
 %   if StrideableIndex:
-  public typealias Indices = CountableRange<${Index}>
+  public typealias Indices = Range<${Index}>
 %  elif Traversal == 'RandomAccess':
   // FIXME: this shouldn't be necessary, should come by default
   public typealias Indices = DefaultIndices<${Self}<Element>>

stdlib/private/StdlibCollectionUnittest/RangeSelection.swift

@@ -55,10 +55,6 @@ public enum RangeSelection {
     }
   }
 
-  public func countableRange<C : Collection>(in c: C) -> CountableRange<C.Index> {
-    return CountableRange(range(in: c))
-  }
-
   public func closedRange<C : Collection>(in c: C) -> ClosedRange<C.Index> {
     switch self {
       case .emptyRange: fatalError("Closed range cannot be empty")
@@ -87,8 +83,4 @@ public enum RangeSelection {
         return start...end
     }
   }
-
-  public func countableClosedRange<C : Collection>(in c: C) -> CountableClosedRange<C.Index> {
-    return CountableClosedRange(closedRange(in: c))
-  }
 }

stdlib/private/StdlibUnittest/StdlibUnittest.swift.gyb

@@ -319,13 +319,8 @@ public func expectGE<T : Comparable>(_ lhs: T, _ rhs: T, ${TRACE}) {
   }
 }
 
-% for OtherRange in ['Range', 'CountableRange', 'ClosedRange', 'CountableClosedRange']:
-extension Range
-%   if 'Countable' in OtherRange:
-  where
-  Bound : Strideable, Bound.Stride : SignedInteger
-%   end
-{
+% for OtherRange in ['Range', 'ClosedRange']:
+extension Range {
   internal func _contains(_ other: ${OtherRange}<Bound>) -> Bool {
     if other.lowerBound < lowerBound { return false }
 %   if 'Closed' in OtherRange:
@@ -338,7 +333,7 @@ extension Range
 }
 % end
 
-% for Range in ['Range', 'CountableRange', 'ClosedRange', 'CountableClosedRange']:
+% for Range in ['Range', 'ClosedRange']:
 public func expectTrapping<Bound>(
   _ point: Bound, in range: ${Range}<Bound>, ${TRACE}
 ) {
@@ -2433,31 +2428,16 @@ public func expectEqualsUnordered<T : Comparable>(
   expectEqualSequence(x, y, ${trace})
 }
 
-public func expectEqualsUnordered<
-  T : Strideable
->(
+public func expectEqualsUnordered<T : Strideable>(
   _ expected: Range<T>, _ actual: [T], ${TRACE}
 ) where T.Stride: SignedInteger {
-  expectEqualsUnordered(
-    CountableRange(uncheckedBounds:
-      (lower: expected.lowerBound, upper: expected.upperBound)),
-    actual,
-    ${trace},
-    showFrame: false)
-}
-
-public func expectEqualsUnordered<T : Strideable>(
-  _ expected: CountableRange<T>, _ actual: [T], ${TRACE}
-) {
   if expected.count != actual.count {
     expectationFailure("expected elements: \"\(expected)\"\n"
       + "actual: \"\(actual)\" (of type \(String(reflecting: type(of: actual))))",
       trace: ${trace})
   }
-  let r = Range(uncheckedBounds:
-    (lower: expected.lowerBound, upper: expected.upperBound))
   for e in actual {
-    if !r.contains(e) {
+    if !expected.contains(e) {
       expectationFailure("expected elements: \"\(expected)\"\n"
         + "actual: \"\(actual)\" (of type \(String(reflecting: type(of: actual))))",
         trace: ${trace})

stdlib/public/SDK/CoreAudio/CoreAudio.swift

@@ -172,6 +172,6 @@ extension UnsafeMutableAudioBufferListPointer
     }
   }
 
-  public typealias Indices = CountableRange<Int>
+  public typealias Indices = Range<Int>
 }
 

stdlib/public/SDK/Dispatch/Data.swift

@@ -154,7 +154,7 @@ public struct DispatchData : RandomAccessCollection, _ObjectiveCBridgeable {
 		}
 	}
 
-	private func _copyBytesHelper(to pointer: UnsafeMutableRawPointer, from range: CountableRange<Index>) {
+	private func _copyBytesHelper(to pointer: UnsafeMutableRawPointer, from range: Range<Index>) {
 		var copiedCount = 0
 		if range.isEmpty { return }
 		let rangeSize = range.count
@@ -195,8 +195,8 @@ public struct DispatchData : RandomAccessCollection, _ObjectiveCBridgeable {
 	/// - parameter pointer: A pointer to the buffer you wish to copy the bytes into.
 	/// - parameter range: The range in the `Data` to copy.
 	/// - warning: This method does not verify that the contents at pointer have enough space to hold the required number of bytes.
-	@available(swift, deprecated: 4, message: "Use copyBytes(to: UnsafeMutableRawBufferPointer, from: CountableRange<Index>) instead")
-	public func copyBytes(to pointer: UnsafeMutablePointer<UInt8>, from range: CountableRange<Index>) {
+	@available(swift, deprecated: 4, message: "Use copyBytes(to: UnsafeMutableRawBufferPointer, from: Range<Index>) instead")
+	public func copyBytes(to pointer: UnsafeMutablePointer<UInt8>, from range: Range<Index>) {
 		_copyBytesHelper(to: pointer, from: range)
 	}
 
@@ -205,7 +205,7 @@ public struct DispatchData : RandomAccessCollection, _ObjectiveCBridgeable {
 	/// - parameter pointer: A pointer to the buffer you wish to copy the bytes into. The buffer must be large
 	///	enough to hold `count` bytes.
 	/// - parameter range: The range in the `Data` to copy.
-	public func copyBytes(to pointer: UnsafeMutableRawBufferPointer, from range: CountableRange<Index>) {
+	public func copyBytes(to pointer: UnsafeMutableRawBufferPointer, from range: Range<Index>) {
 		assert(range.count <= pointer.count, "Buffer too small to copy \(range.count) bytes")
 		guard pointer.baseAddress != nil else { return }
 		_copyBytesHelper(to: pointer.baseAddress!, from: range)
@@ -218,11 +218,11 @@ public struct DispatchData : RandomAccessCollection, _ObjectiveCBridgeable {
 	/// - parameter buffer: A buffer to copy the data into.
 	/// - parameter range: A range in the data to copy into the buffer. If the range is empty, this function will return 0 without copying anything. If the range is nil, as much data as will fit into `buffer` is copied.
 	/// - returns: Number of bytes copied into the destination buffer.
-	public func copyBytes<DestinationType>(to buffer: UnsafeMutableBufferPointer<DestinationType>, from range: CountableRange<Index>? = nil) -> Int {
+	public func copyBytes<DestinationType>(to buffer: UnsafeMutableBufferPointer<DestinationType>, from range: Range<Index>? = nil) -> Int {
 		let cnt = count
 		guard cnt > 0 else { return 0 }
 
-		let copyRange : CountableRange<Index>
+		let copyRange : Range<Index>
 		if let r = range {
 			guard !r.isEmpty else { return 0 }
 			precondition(r.startIndex >= 0)
@@ -262,7 +262,7 @@ public struct DispatchData : RandomAccessCollection, _ObjectiveCBridgeable {
 	/// Return a new copy of the data in a specified range.
 	///
 	/// - parameter range: The range to copy.
-	public func subdata(in range: CountableRange<Index>) -> DispatchData {
+	public func subdata(in range: Range<Index>) -> DispatchData {
 		let subrange = __dispatch_data_create_subrange(
 			__wrapped, range.startIndex, range.endIndex - range.startIndex)
 		return DispatchData(data: subrange)

stdlib/public/SDK/Foundation/Data.swift

@@ -996,7 +996,7 @@ public struct Data : ReferenceConvertible, Equatable, Hashable, RandomAccessColl
     public typealias Base64DecodingOptions = NSData.Base64DecodingOptions
 
     public typealias Index = Int
-    public typealias Indices = CountableRange<Int>
+    public typealias Indices = Range<Int>
 
     @_versioned internal var _backing : _DataStorage
     @_versioned internal var _sliceRange: Range<Index>
@@ -1537,12 +1537,6 @@ public struct Data : ReferenceConvertible, Equatable, Hashable, RandomAccessColl
         }
     }
 
-    @inline(__always)
-    public mutating func replaceSubrange(_ subrange: CountableRange<Index>, with data: Data) {
-        let range: Range<Int> = subrange.lowerBound..<subrange.upperBound
-        replaceSubrange(range, with: data)
-    }
-    
     /// Replace a region of bytes in the data with new bytes from a buffer.
     ///
     /// This will resize the data if required, to fit the entire contents of `buffer`.
@@ -1743,7 +1737,7 @@ public struct Data : ReferenceConvertible, Equatable, Hashable, RandomAccessColl
         return i + 1
     }
 
-    public var indices: CountableRange<Int> {
+    public var indices: Range<Int> {
         @inline(__always)
         get {
             return startIndex..<endIndex