[NoncopyableGenerics] add basic end-to-end test

Author: kavon

test/Interpreter/moveonly_generics.swift

@@ -0,0 +1,117 @@
+// RUN: %target-run-simple-swift(-Xfrontend -sil-verify-all -enable-experimental-feature NoncopyableGenerics)
+// RUN: %target-run-simple-swift(-O -Xfrontend -sil-verify-all -enable-experimental-feature NoncopyableGenerics)
+
+// REQUIRES: executable_test
+// REQUIRES: asserts
+
+// Needed due to limitations of autoclosures and noncopyable types.
+func eagerAssert(_ b: Bool, _ line: Int = #line) {
+  guard b else { fatalError("assertion failure on line \(line)") }
+}
+
+///---------------------
+/// MARK: a Swift x Haskell limited-edition stdlib
+/// ---------------------
+
+
+
+/// MARK: Ord aka 'Comparable'
+protocol Ord: ~Copyable {
+  func compare(_ other: borrowing Self) -> Ordering
+}
+
+enum Ordering {
+  case LT
+  case EQ
+  case GT
+
+  static func compare<T: Comparable>(_ a: borrowing T, _ b: borrowing T) -> Ordering {
+    if (a < b) { return .LT }
+    if (a > b) { return .GT }
+    eagerAssert(a == b)
+    return .EQ
+  }
+}
+
+extension Ord {
+  static func <(_ a: borrowing Self, _ b: borrowing Self) -> Bool {
+    return a.compare(b) == .LT
+  }
+  static func <=(_ a: borrowing Self, _ b: borrowing Self) -> Bool {
+    return !(a > b)
+  }
+  static func >(_ a: borrowing Self, _ b: borrowing Self) -> Bool {
+    return a.compare(b) == .GT
+  }
+  static func >=(_ a: borrowing Self, _ b: borrowing Self) -> Bool {
+    return !(a < b)
+  }
+  static func ==(_ a: borrowing Self, _ b: borrowing Self) -> Bool {
+    a.compare(b) == .EQ
+  }
+  static func !=(_ a: borrowing Self, _ b: borrowing Self) -> Bool {
+    !(a == b)
+  }
+}
+
+/// MARK: Maybe aka 'Optional'
+enum Maybe<Val: ~Copyable>: ~Copyable {
+  case just(Val)
+  case none
+
+  // NOTE: a 'consuming' version of the unfortunately 'borrowing' map from the stdlib.
+  consuming func consumingMap<U: ~Copyable>(_ fn: (consuming Val) throws -> U) rethrows -> Maybe<U> {
+    // rdar://117638878 (MoveOnlyAddressChecker crashes with generic associated value in enum)
+    fatalError("need to fix rdar://117638878")
+//     return switch consume self {
+//       case let .just(val): .just(try fn(val))
+//       case .none: .none
+//     }
+  }
+}
+
+// NOTE: temporary
+extension Maybe: Copyable where Val: Copyable {}
+
+
+/// MARK: beginning of tests
+
+struct FileDescriptor: ~Copyable, Ord {
+  let id: Int
+
+  func compare(_ other: borrowing FileDescriptor) -> Ordering {
+    return .compare(id, other.id)
+  }
+
+  deinit { print("calling deinit!") }
+}
+
+class Shared<T: ~Copyable> {
+  let value: T
+  init(_ val: consuming T) { self.value = val }
+  func borrow<V>(_ f: (borrowing T) throws -> V) rethrows -> V {
+    return try f(value)
+  }
+}
+
+defer { testOrd() }
+func testOrd() {
+  let stderr = Shared(FileDescriptor(id: 1))
+  let stdout = Shared(FileDescriptor(id: 0))
+  stdout.borrow { out in
+    stderr.borrow { err in
+      eagerAssert(err > out)
+      eagerAssert(out < err)
+      eagerAssert(out != err)
+    }
+  }
+}
+
+defer { testMaybe() }
+func testMaybe() {
+  let mayb = Maybe.just(FileDescriptor(id: 0));
+  switch consume mayb {
+    case let .just(fd): eagerAssert(fd.id == 0)
+    case .none: eagerAssert(false)
+  }
+}