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// RUN: %target-run-simple-swift(-Xfrontend -disable-availability-checking -parse-as-library -Xfrontend -enable-copy-propagation) | %FileCheck %s
// REQUIRES: executable_test
// REQUIRES: concurrency
// REQUIRES: concurrency_runtime
// UNSUPPORTED: back_deployment_runtime
// =============================================================================
// = Declarations {{ =
// =============================================================================
class C {
init(_ d: D) {
self.d = d
}
weak var d: D?
func foo(_ string: String) {
d?.cWillFoo(self, string)
}
}
class D {
func cWillFoo(_ c: C, _ string: String) {
print(#function, string)
}
}
class DataWrapper {
var pointer: UnsafeMutableRawBufferPointer
init(count: Int) {
pointer = UnsafeMutableRawBufferPointer.allocate(byteCount: count * MemoryLayout<Int>.stride, alignment: MemoryLayout<Int>.alignment)
}
var bytes: UnsafeMutableRawBufferPointer { return pointer }
deinit {
pointer.deallocate()
}
}
var fileHandleMap: [Int32 : String] = [:]
func openTheFile(_ path: String) -> Int32 {
let fd: Int32 = 42
precondition(fileHandleMap[fd] == nil)
fileHandleMap[fd] = path
return fd
}
func closeTheFile(_ fd: Int32) {
fileHandleMap.removeValue(forKey: fd)
}
func writeToTheFile(_ fd: Int32) {
precondition(fileHandleMap[fd] != nil)
}
class FileHandleWrapper {
var handle: Int32? = nil
func open(path: String) {
let fd = openTheFile(path)
if fd >= 0 {
handle = fd
}
}
func close() {
if let fd = handle {
closeTheFile(fd)
handle = nil
}
}
deinit {
if let fd = handle {
closeTheFile(fd)
}
}
}
// =============================================================================
// = Declarations }} =
// =============================================================================
// =============================================================================
// = Tests {{ =
// =============================================================================
func test_localLet_keepsObjectAliveBeyondCallToClassWithWeakReference() {
let d = D()
let c = C(d)
// CHECK: cWillFoo{{.*}} test_localLet_keepsObjectAliveBeyondCallToClassWithWeakReference
c.foo(#function)
}
func test_localVar_keepsObjectAliveBeyondCallToClassWithWeakReference() {
var d = D()
let c = C(d)
// Reenable with rdar://86271875
// CHECK: cWillFoo{{.*}} test_localVar_keepsObjectAliveBeyondCallToClassWithWeakReference
c.foo(#function)
}
func test_localLet_keepsObjectAliveBeyondCallToClassWithPointer_doit(_ input: [UInt8]) {
let data = DataWrapper(count: input.count)
data.bytes.copyBytes(from: input)
}
func test_localLet_keepsObjectAliveBeyondCallToClassWithPointer() {
test_localLet_keepsObjectAliveBeyondCallToClassWithPointer_doit([1,2,3,4,50])
}
func test_localVar_keepsObjectAliveBeyondCallToClassWithPointer_doit(_ input: [UInt8]) {
let data = DataWrapper(count: input.count)
data.bytes.copyBytes(from: input)
}
func test_localVar_keepsObjectAliveBeyondCallToClassWithPointer() {
test_localVar_keepsObjectAliveBeyondCallToClassWithPointer_doit([1,2,3,4,50])
}
func test_localLet_keepsObjectAliveBeyondCallToSynchronizationPointFunction_doit(_ path: String) {
var file = FileHandleWrapper()
file.open(path: path)
// Retrieving 'fd' is the last use of 'file'
guard let fd = file.handle else { return }
// 'fd' has now been closed. The subsequent write will fail.
writeToTheFile(fd)
}
func test_localLet_keepsObjectAliveBeyondCallToSynchronizationPointFunction() {
test_localLet_keepsObjectAliveBeyondCallToSynchronizationPointFunction_doit("blue")
}
func test_localVar_keepsObjectAliveBeyondCallToSynchronizationPointFunction_doit(_ path: String) {
var file = FileHandleWrapper()
file.open(path: path)
// Retrieving 'fd' is the last use of 'file'
guard let fd = file.handle else { return }
// 'fd' has now been closed. The subsequent write will fail.
writeToTheFile(fd)
}
func test_localVar_keepsObjectAliveBeyondCallToSynchronizationPointFunction() {
test_localVar_keepsObjectAliveBeyondCallToSynchronizationPointFunction_doit("blue")
}
func do_foo(_ work: () -> ()) {
work()
}
class Fooer {
__consuming func foo() {
weak var weakSelf = self
do_foo {
weakSelf?.foo1()
weakSelf?.foo2()
}
}
func foo1() {
// CHECK: Fooer foo1
print(type(of: self), #function)
}
func foo2() {
// CHECK: Fooer foo2
print(type(of: self), #function)
}
}
func test_self_keepsObjectAliveBeyond_callTo_functionTakingClosureCapturingWeakVar() {
Fooer().foo()
}
func do_foo_async(_ work: @escaping () -> ()) -> Task<Void, Never> {
Task {
work()
}
}
class FooerAsync {
var strongSelf: FooerAsync?
__consuming func foo() -> Task<Void, Never> {
weak var weakSelf = self
strongSelf = self
return do_foo_async {
// At this point, strongSelf is keeping the object alive.
weakSelf?.foo1()
// By this point, strongSelf has been nil'd. However, self in the
// enclosing foo() may still be keeping the object alive, depending on how
// the closure was scheduled.
weakSelf?.foo2()
}
}
func foo1() {
// CHECK: FooerAsync foo1
print(type(of: self), #function)
strongSelf = nil
}
func foo2() {
print(type(of: self), #function)
}
}
func test_repeatedLoadWeakSelf() -> Task<Void, Never> {
FooerAsync().foo()
}
// =============================================================================
// = Tests }} =
// =============================================================================
@main struct Main {
static func main() async {
test_localLet_keepsObjectAliveBeyondCallToClassWithWeakReference()
test_localVar_keepsObjectAliveBeyondCallToClassWithWeakReference()
test_localLet_keepsObjectAliveBeyondCallToClassWithPointer()
test_localVar_keepsObjectAliveBeyondCallToClassWithPointer()
test_localLet_keepsObjectAliveBeyondCallToSynchronizationPointFunction()
test_localVar_keepsObjectAliveBeyondCallToSynchronizationPointFunction()
test_self_keepsObjectAliveBeyond_callTo_functionTakingClosureCapturingWeakVar()
await test_repeatedLoadWeakSelf().value
}
}
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