[NOMERGE] Build the standard library in Swift 4 mode

cmake/modules/SwiftSource.cmake

@@ -261,12 +261,12 @@ function(_compile_swift_files
     endif()
   endif()
 
-  # Force swift 3 compatibility mode for Standard Library and overlay.
-  if (SWIFTFILE_IS_STDLIB OR SWIFTFILE_IS_SDK_OVERLAY)
-    list(APPEND swift_flags "-swift-version" "3")
+  if (SWIFTFILE_IS_STDLIB)
+    list(APPEND swift_flags "-swift-version" "4")
   endif()
 
   if(SWIFTFILE_IS_SDK_OVERLAY)
+    list(APPEND swift_flags "-swift-version" "3")
     list(APPEND swift_flags "-autolink-force-load")
   endif()
 

stdlib/private/StdlibCollectionUnittest/CheckSequenceType.swift

@@ -1922,7 +1922,7 @@ self.test("\(testNamePrefix)._preprocessingPass/semantics") {
     let s = makeWrappedSequence(test.sequence.map(OpaqueValue.init))
     var wasInvoked = false
     let result = s._preprocessingPass {
-      (sequence) -> OpaqueValue<Int> in
+      () -> OpaqueValue<Int> in
       wasInvoked = true
 
       expectEqualSequence(
@@ -1945,7 +1945,7 @@ self.test("\(testNamePrefix)._preprocessingPass/semantics") {
     var result: OpaqueValue<Int>?
     do {
       result = try s._preprocessingPass {
-        _ -> OpaqueValue<Int> in
+        () -> OpaqueValue<Int> in
         wasInvoked = true
         throw TestError.error2
       }

stdlib/private/StdlibUnittest/StdlibCoreExtras.swift

@@ -27,6 +27,10 @@ import Foundation
 // useful in tests, and stdlib does not have such facilities yet.
 //
 
+func findSubstring(_ haystack: Substring, _ needle: String) -> String.Index? {
+  return findSubstring(String(haystack._ephemeralContent), needle)
+}
+
 func findSubstring(_ string: String, _ substring: String) -> String.Index? {
   if substring.isEmpty {
     return string.startIndex
@@ -48,7 +52,7 @@ func findSubstring(_ string: String, _ substring: String) -> String.Index? {
     while true {
       if needleIndex == needle.endIndex {
         // if we hit the end of the search string, we found the needle
-        return matchStartIndex.samePosition(in: string)
+        return matchStartIndex
       }
       if matchIndex == haystack.endIndex {
         // if we hit the end of the string before finding the end of the needle,
@@ -149,7 +153,7 @@ extension MutableCollection
     var f = subrange.lowerBound
     var l = index(before: subrange.upperBound)
     while f < l {
-      swap(&self[f], &self[l])
+      swapAt(f, l)
       formIndex(after: &f)
       formIndex(before: &l)
     }
@@ -195,7 +199,7 @@ extension MutableCollection
         repeat {
           formIndex(before: &j)
         } while !(elementAtBeforeI < self[j])
-        swap(&self[beforeI], &self[j])
+        swapAt(beforeI, j)
         _reverseSubrange(i..<endIndex)
         return .success
       }

stdlib/private/StdlibUnittest/StdlibUnittest.swift.gyb

@@ -766,7 +766,7 @@ struct _ParentProcess {
     parameter: Int?
   ) -> (anyExpectFailed: Bool, seenExpectCrash: Bool,
         status: ProcessTerminationStatus?,
-        crashStdout: [String], crashStderr: [String]) {
+        crashStdout: [Substring], crashStderr: [Substring]) {
     if _pid == nil {
       _spawnChild()
     }
@@ -790,15 +790,15 @@ struct _ParentProcess {
     var stderrSeenCrashDelimiter = false
     var stdoutEnd = false
     var stderrEnd = false
-    var capturedCrashStdout: [String] = []
-    var capturedCrashStderr: [String] = []
+    var capturedCrashStdout: [Substring] = []
+    var capturedCrashStderr: [Substring] = []
     var anyExpectFailedInChild = false
 
     func processLine(_ line: String, isStdout: Bool) -> (done: Bool, Void) {
-      var line = line
+      var line = line[...]
       if let index = findSubstring(line, _stdlibUnittestStreamPrefix) {
         let controlMessage =
-            line[index..<line.endIndex]._split(separator: ";")
+            line[index..<line.endIndex].split(separator: ";")
         switch controlMessage[1] {
         case "expectCrash":
           if isStdout {
@@ -830,7 +830,7 @@ struct _ParentProcess {
         if stderrSeenCrashDelimiter {
           capturedCrashStderr.append(line)
           if findSubstring(line, _crashedPrefix) != nil {
-            line = "OK: saw expected \"\(line.lowercased())\""
+            line = "OK: saw expected \"\(line.lowercased())\""[...]
           }
         }
       }
@@ -937,8 +937,8 @@ struct _ParentProcess {
 
     var expectCrash = false
     var childTerminationStatus: ProcessTerminationStatus?
-    var crashStdout: [String] = []
-    var crashStderr: [String] = []
+    var crashStdout: [Substring] = []
+    var crashStderr: [Substring] = []
     if _runTestsInProcess {
       if t.stdinText != nil {
         print("The test \(fullTestName) requires stdin input and can't be run in-process, marking as failed")
@@ -2380,11 +2380,11 @@ public func expectEqualsUnordered<
   Expected.Iterator.Element == Actual.Iterator.Element {
 
   let x: [Expected.Iterator.Element] =
-    expected.sorted(by: compose(compare, { $0.isLT() }))
+    expected.sorted { compare($0, $1).isLT() }
   let y: [Actual.Iterator.Element] =
-    actual.sorted(by: compose(compare, { $0.isLT() }))
+    actual.sorted { compare($0, $1).isLT() }
   expectEqualSequence(
-    x, y, ${trace}, sameValue: compose(compare, { $0.isEQ() }))
+    x, y, ${trace}, sameValue: { compare($0, $1).isEQ() })
 }
 
 public func expectEqualsUnordered<
@@ -2534,12 +2534,6 @@ public func expectEqualUnicodeScalars(
   }
 }
 
-func compose<A, B, C>(_ f: @escaping (A) -> B, _ g: @escaping (B) -> C) -> (A) -> C {
-  return { a in
-    return g(f(a))
-  }
-}
-
 // ${'Local Variables'}:
 // eval: (read-only-mode 1)
 // End:

stdlib/public/core/DoubleWidth.swift.gyb

@@ -499,11 +499,13 @@ public struct DoubleWidth<Base : FixedWidthInteger> :
 
     lhs._storage.low >>= rhs._storage.low
     if Base.bitWidth > rhs._storage.low {
-      lhs._storage.low |= Low(extendingOrTruncating: lhs._storage.high <<
-        numericCast(numericCast(Base.bitWidth) - rhs._storage.low))
+      lhs._storage.low |= Low(
+        extendingOrTruncating:
+        lhs._storage.high << (numericCast(Base.bitWidth) - rhs._storage.low))
     } else {
-      lhs._storage.low |= Low(extendingOrTruncating: lhs._storage.high >>
-        numericCast(rhs._storage.low - numericCast(Base.bitWidth)))
+      lhs._storage.low |= Low(
+        extendingOrTruncating: lhs._storage.high >>
+        (rhs._storage.low - numericCast(Base.bitWidth)))
     }
     lhs._storage.high >>= High(extendingOrTruncating: rhs._storage.low)
   }

stdlib/public/core/ExistentialCollection.swift.gyb

@@ -308,29 +308,29 @@ internal class _AnyRandomAccessCollectionBox<Element>
   @_versioned
   @_inlineable
   internal func _index(
-    _ i: _AnyIndexBox, offsetBy n: IntMax
+    _ i: _AnyIndexBox, offsetBy n: Int64
   ) -> _AnyIndexBox {
     _abstract()
   }
 
   @_versioned
   @_inlineable
   internal func _index(
-    _ i: _AnyIndexBox, offsetBy n: IntMax, limitedBy limit: _AnyIndexBox
+    _ i: _AnyIndexBox, offsetBy n: Int64, limitedBy limit: _AnyIndexBox
   ) -> _AnyIndexBox? {
     _abstract()
   }
 
   @_versioned
   @_inlineable
-  internal func _formIndex(_ i: inout _AnyIndexBox, offsetBy n: IntMax) {
+  internal func _formIndex(_ i: inout _AnyIndexBox, offsetBy n: Int64) {
     _abstract()
   }
 
   @_versioned
   @_inlineable
   internal func _formIndex(
-    _ i: inout _AnyIndexBox, offsetBy n: IntMax, limitedBy limit: _AnyIndexBox
+    _ i: inout _AnyIndexBox, offsetBy n: Int64, limitedBy limit: _AnyIndexBox
   ) -> Bool {
     _abstract()
   }
@@ -339,7 +339,7 @@ internal class _AnyRandomAccessCollectionBox<Element>
   @_inlineable
   internal func _distance(
     from start: _AnyIndexBox, to end: _AnyIndexBox
-  ) -> IntMax {
+  ) -> Int64 {
     _abstract()
   }
 
@@ -357,7 +357,7 @@ internal class _AnyRandomAccessCollectionBox<Element>
   */
 
   @_versioned
-  internal var _count: IntMax { _abstract() }
+  internal var _count: Int64 { _abstract() }
 
   // TODO: swift-3-indexing-model: forward the following methods.
   /*
@@ -609,7 +609,7 @@ internal final class _${Kind}Box<S : ${Kind}> : _Any${Kind}Box<S.Iterator.Elemen
   @_versioned
   @_inlineable
   internal override func _index(
-    _ i: _AnyIndexBox, offsetBy n: IntMax
+    _ i: _AnyIndexBox, offsetBy n: Int64
   ) -> _AnyIndexBox {
     return _IndexBox(_base: _base.index(_unbox(i), offsetBy: numericCast(n)))
   }
@@ -618,7 +618,7 @@ internal final class _${Kind}Box<S : ${Kind}> : _Any${Kind}Box<S.Iterator.Elemen
   @_inlineable
   internal override func _index(
     _ i: _AnyIndexBox,
-    offsetBy n: IntMax,
+    offsetBy n: Int64,
     limitedBy limit: _AnyIndexBox
   ) -> _AnyIndexBox? {
     return _base.index(
@@ -631,7 +631,7 @@ internal final class _${Kind}Box<S : ${Kind}> : _Any${Kind}Box<S.Iterator.Elemen
   @_versioned
   @_inlineable
   internal override func _formIndex(
-    _ i: inout _AnyIndexBox, offsetBy n: IntMax
+    _ i: inout _AnyIndexBox, offsetBy n: Int64
   ) {
     if let box = i as? _IndexBox<S.Index> {
       return _base.formIndex(&box._base, offsetBy: numericCast(n))
@@ -642,7 +642,7 @@ internal final class _${Kind}Box<S : ${Kind}> : _Any${Kind}Box<S.Iterator.Elemen
   @_versioned
   @_inlineable
   internal override func _formIndex(
-    _ i: inout _AnyIndexBox, offsetBy n: IntMax, limitedBy limit: _AnyIndexBox
+    _ i: inout _AnyIndexBox, offsetBy n: Int64, limitedBy limit: _AnyIndexBox
   ) -> Bool {
     if let box = i as? _IndexBox<S.Index> {
       return _base.formIndex(
@@ -658,13 +658,13 @@ internal final class _${Kind}Box<S : ${Kind}> : _Any${Kind}Box<S.Iterator.Elemen
   internal override func _distance(
     from start: _AnyIndexBox,
     to end: _AnyIndexBox
-  ) -> IntMax {
+  ) -> Int64 {
     return numericCast(_base.distance(from: _unbox(start), to: _unbox(end)))
   }
 
   @_versioned
   @_inlineable
-  internal override var _count: IntMax {
+  internal override var _count: Int64 {
     return numericCast(_base.count)
   }
 
@@ -1079,7 +1079,7 @@ public struct ${Self}<Element>
 %   end
 
   public typealias Index = AnyIndex
-  public typealias IndexDistance = IntMax
+  public typealias IndexDistance = Int64
 
   /// The position of the first element in a non-empty collection.
   ///
@@ -1144,22 +1144,22 @@ public struct ${Self}<Element>
   }
 
   @_inlineable
-  public func index(_ i: AnyIndex, offsetBy n: IntMax) -> AnyIndex {
+  public func index(_ i: AnyIndex, offsetBy n: Int64) -> AnyIndex {
     return AnyIndex(_box: _box._index(i._box, offsetBy: n))
   }
 
   @_inlineable
   public func index(
     _ i: AnyIndex,
-    offsetBy n: IntMax,
+    offsetBy n: Int64,
     limitedBy limit: AnyIndex
   ) -> AnyIndex? {
     return _box._index(i._box, offsetBy: n, limitedBy: limit._box)
       .map { AnyIndex(_box:$0) }
   }
 
   @_inlineable
-  public func formIndex(_ i: inout AnyIndex, offsetBy n: IntMax) {
+  public func formIndex(_ i: inout AnyIndex, offsetBy n: Int64) {
     if _isUnique(&i._box) {
       return _box._formIndex(&i._box, offsetBy: n)
     } else {
@@ -1170,7 +1170,7 @@ public struct ${Self}<Element>
   @_inlineable
   public func formIndex(
     _ i: inout AnyIndex,
-    offsetBy n: IntMax,
+    offsetBy n: Int64,
     limitedBy limit: AnyIndex
   ) -> Bool {
     if _isUnique(&i._box) {
@@ -1185,7 +1185,7 @@ public struct ${Self}<Element>
   }
 
   @_inlineable
-  public func distance(from start: AnyIndex, to end: AnyIndex) -> IntMax {
+  public func distance(from start: AnyIndex, to end: AnyIndex) -> Int64 {
     return _box._distance(from: start._box, to: end._box)
   }
 
@@ -1199,7 +1199,7 @@ public struct ${Self}<Element>
 % end
   /// - Complexity: ${'O(1)' if Traversal == 'RandomAccess' else 'O(*n*)'}
   @_inlineable
-  public var count: IntMax {
+  public var count: Int64 {
     return _box._count
   }
 

stdlib/public/core/HashedCollections.swift.gyb

@@ -1739,9 +1739,9 @@ public struct Dictionary<Key : Hashable, Value> :
       self = Dictionary(minimumCapacity: keysAndValues.underestimatedCount)
       // '_MergeError.keyCollision' is caught and handled with an appropriate
       // error message one level down, inside _variantBuffer.merge(_:...).
-      try! _variantBuffer.merge(keysAndValues, uniquingKeysWith: { _ in
-        throw _MergeError.keyCollision
-      })
+      try! _variantBuffer.merge(
+        keysAndValues,
+        uniquingKeysWith: { _, _ in throw _MergeError.keyCollision})
     }
   }
 
@@ -5885,7 +5885,7 @@ extension ${Self} {
   @_inlineable
   @available(swift, obsoleted: 4.0)
   public func filter(
-    _ isIncluded: (Element) throws -> Bool
+    _ isIncluded: (Element) throws -> Bool, obsoletedInSwift4: () = ()
   ) rethrows -> [Element] {
     var result: [Element] = []
     for x in self {

stdlib/public/core/Integers.swift.gyb

@@ -2125,7 +2125,7 @@ extension FixedWidthInteger {
   ///
   /// [identity element]:http://en.wikipedia.org/wiki/Identity_element
   /// [fixed point]:http://en.wikipedia.org/wiki/Fixed_point_(mathematics)
-  @available(swift, deprecated: 3.1, obsoleted: 4.0, message: "Use 0")
+  @available(swift, deprecated: 3.1, obsoleted: 4.1, message: "Use 0")
   public static var allZeros: Self { return 0 }
 
   @_inlineable
@@ -2933,7 +2933,7 @@ ${assignmentOperatorComment(x.operator, True)}
 % end
 
   @available(swift, obsoleted: 4.0, message: "Use initializers instead")
-  public func to${U}IntMax() -> ${U}IntMax {
+  public func to${U}IntMax() -> ${U}Int64 {
     return numericCast(self)
   }
 
@@ -3169,15 +3169,15 @@ extension SignedNumeric where Self : Comparable {
 @available(swift, obsoleted: 4)
 extension BinaryInteger {
   @available(swift, obsoleted: 4)
-  public func toIntMax() -> IntMax {
-    return IntMax(self)
+  public func toIntMax() -> Int64 {
+    return Int64(self)
   }
 }
 
 extension UnsignedInteger {
   @available(swift, obsoleted: 4)
-  public func toUIntMax() -> UIntMax {
-    return UIntMax(self)
+  public func toUIntMax() -> UInt64 {
+    return UInt64(self)
   }
 }