Use availability macro insteada of macOS 9999 in Concurrency tests

Author: aschwaighofer

test/Concurrency/Runtime/async_task_locals_basic.swift

@@ -54,7 +54,7 @@ func printTaskLocalAsync<V>(
   printTaskLocal(key, expected, file: file, line: line)
 }
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 @discardableResult
 func printTaskLocal<V>(
     _ key: TaskLocal<V>,
@@ -156,7 +156,7 @@ func nested_3_onlyTopContributes() async {
   printTaskLocal(TL.$string) // CHECK-NEXT: TaskLocal<String>(defaultValue: <undefined>) (<undefined>)
 }
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 func nested_3_onlyTopContributesAsync() async {
   await printTaskLocalAsync(TL.$string) // CHECK: TaskLocal<String>(defaultValue: <undefined>) (<undefined>)
   await TL.$string.withValue("one") {
@@ -173,7 +173,7 @@ func nested_3_onlyTopContributesAsync() async {
   await printTaskLocalAsync(TL.$string) // CHECK-NEXT: TaskLocal<String>(defaultValue: <undefined>) (<undefined>)
 }
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 func nested_3_onlyTopContributesMixed() async {
   await printTaskLocalAsync(TL.$string) // CHECK: TaskLocal<String>(defaultValue: <undefined>) (<undefined>)
   await TL.$string.withValue("one") {

test/Concurrency/Runtime/async_task_locals_copy_to_async.swift

@@ -8,15 +8,15 @@
 // UNSUPPORTED: use_os_stdlib
 // UNSUPPORTED: back_deployment_runtime
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 enum TL {
   @TaskLocal
   static var number: Int = 0
   @TaskLocal
   static var other: Int = 0
 }
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 @discardableResult
 func printTaskLocal<V>(
     _ key: TaskLocal<V>,
@@ -34,7 +34,7 @@ func printTaskLocal<V>(
 
 // ==== ------------------------------------------------------------------------
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 func copyTo_async() async {
   await TL.$number.withValue(1111) {
     printTaskLocal(TL.$number) // CHECK: TaskLocal<Int>(defaultValue: 0) (1111)
@@ -58,7 +58,7 @@ func copyTo_async() async {
   }
 }
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 func copyTo_async_noWait() async {
   print(#function)
   TL.$number.withValue(1111) {
@@ -80,7 +80,7 @@ func copyTo_async_noWait() async {
   await Task.sleep(2 * second)
 }
 
-@available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
+@available(SwiftStdlib 5.5, *)
 @main struct Main {
   static func main() async {
     await copyTo_async()