Merge pull request swiftlang#414 from stmontgomery/XCTestExpectation-Sendable

Make XCTestExpectation Sendable

Author: stmontgomery

Sources/XCTest/Public/Asynchronous/XCTestExpectation.swift

@@ -11,7 +11,7 @@
 //
 
 /// Expectations represent specific conditions in asynchronous testing.
-open class XCTestExpectation {
+open class XCTestExpectation: @unchecked Sendable {
 
     private static var currentMonotonicallyIncreasingToken: UInt64 = 0
     private static func queue_nextMonotonicallyIncreasingToken() -> UInt64 {

Tests/Functional/Asynchronous/ExpectationsWithConcurrency/main.swift

@@ -0,0 +1,12 @@
+// RUN: %{swiftc} %s -typecheck -warn-concurrency -warnings-as-errors
+
+#if os(macOS)
+    import SwiftXCTest
+#else
+    import XCTest
+#endif
+
+let expectation = XCTestExpectation()
+Task.detached {
+    expectation.fulfill()
+}