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[Concurrency] Complement assume... APIs with the assert and precondition ones (#64062)
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‎stdlib/public/Concurrency/ExecutorAssertions.swift

Lines changed: 155 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -2,7 +2,7 @@
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//
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// This source file is part of the Swift.org open source project
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//
5-
// Copyright (c) 2021 Apple Inc. and the Swift project authors
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// Copyright (c) 2023 Apple Inc. and the Swift project authors
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// Licensed under Apache License v2.0 with Runtime Library Exception
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//
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// See https://swift.org/LICENSE.txt for license information
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//===----------------------------------------------------------------------===//
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import Swift
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import SwiftShims
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// ==== -----------------------------------------------------------------------
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// MARK: Precondition executors
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/// Unconditionally if the current task is executing on the expected serial executor,
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/// and if not crash the program offering information about the executor mismatch.
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///
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/// This function's effect varies depending on the build flag used:
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///
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/// * In playgrounds and `-Onone` builds (the default for Xcode's Debug
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/// configuration), stops program execution in a debuggable state after
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/// printing `message`.
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///
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/// * In `-O` builds (the default for Xcode's Release configuration), stops
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/// program execution.
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///
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/// * In `-Ounchecked` builds, the optimizer may assume that this function is
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/// never called. Failure to satisfy that assumption is a serious
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/// programming error.
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///
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/// - Parameter executor: the expected current executor
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@available(SwiftStdlib 5.9, *) // FIXME: use @backDeploy(before: SwiftStdlib 5.9)
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public
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func preconditionTaskOnExecutor(
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_ executor: some SerialExecutor,
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message: @autoclosure () -> String = String(),
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file: StaticString = #fileID, line: UInt = #line
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) {
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guard _isDebugAssertConfiguration() || _isReleaseAssertConfiguration() else {
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return
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}
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let expectationCheck = _taskIsCurrentExecutor(executor.asUnownedSerialExecutor().executor)
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/// TODO: implement the logic in-place perhaps rather than delegating to precondition()?
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precondition(expectationCheck,
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// TODO: offer information which executor we actually got
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"Incorrect actor executor assumption; Expected '\(executor)' executor. \(message())",
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file: file, line: line) // short-cut so we get the exact same failure reporting semantics
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}
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/// Unconditionally if the current task is executing on the serial executor of the passed in `actor`,
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/// and if not crash the program offering information about the executor mismatch.
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///
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/// This function's effect varies depending on the build flag used:
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///
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/// * In playgrounds and `-Onone` builds (the default for Xcode's Debug
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/// configuration), stops program execution in a debuggable state after
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/// printing `message`.
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///
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/// * In `-O` builds (the default for Xcode's Release configuration), stops
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/// program execution.
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///
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/// * In `-Ounchecked` builds, the optimizer may assume that this function is
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/// never called. Failure to satisfy that assumption is a serious
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/// programming error.
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///
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/// - Parameter actor: the actor whose serial executor we expect to be the current executor
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@available(SwiftStdlib 5.9, *) // FIXME: use @backDeploy(before: SwiftStdlib 5.9)
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public
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func preconditionTaskOnActorExecutor(
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_ actor: some Actor,
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message: @autoclosure () -> String = String(),
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file: StaticString = #fileID, line: UInt = #line
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) {
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guard _isDebugAssertConfiguration() || _isReleaseAssertConfiguration() else {
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return
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}
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let expectationCheck = _taskIsCurrentExecutor(actor.unownedExecutor.executor)
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// TODO: offer information which executor we actually got
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precondition(expectationCheck,
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// TODO: figure out a way to get the typed repr out of the unowned executor
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"Incorrect actor executor assumption; Expected '\(actor.unownedExecutor)' executor. \(message())",
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file: file, line: line)
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}
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// ==== -----------------------------------------------------------------------
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// MARK: Assert executors
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/// Performs an executor check in debug builds.
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///
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/// * In playgrounds and `-Onone` builds (the default for Xcode's Debug
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/// configuration): If `condition` evaluates to `false`, stop program
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/// execution in a debuggable state after printing `message`.
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///
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/// * In `-O` builds (the default for Xcode's Release configuration),
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/// `condition` is not evaluated, and there are no effects.
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///
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/// * In `-Ounchecked` builds, `condition` is not evaluated, but the optimizer
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/// may assume that it *always* evaluates to `true`. Failure to satisfy that
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/// assumption is a serious programming error.
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///
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/// - Parameter executor: the expected current executor
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@available(SwiftStdlib 5.9, *) // FIXME: use @backDeploy(before: SwiftStdlib 5.9)
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public
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func assertTaskOnExecutor(
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_ executor: some SerialExecutor,
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_ message: @autoclosure () -> String = String(),
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file: StaticString = #fileID, line: UInt = #line
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) {
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guard _isDebugAssertConfiguration() else {
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return
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}
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guard _taskIsCurrentExecutor(executor.asUnownedSerialExecutor().executor) else {
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// TODO: offer information which executor we actually got
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let msg = "Incorrect actor executor assumption; Expected '\(executor)' executor. \(message())"
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/// TODO: implement the logic in-place perhaps rather than delegating to precondition()?
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assertionFailure(msg, file: file, line: line)
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return
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}
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}
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/// Performs an executor check in debug builds.
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///
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/// * In playgrounds and `-Onone` builds (the default for Xcode's Debug
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/// configuration): If `condition` evaluates to `false`, stop program
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/// execution in a debuggable state after printing `message`.
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///
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/// * In `-O` builds (the default for Xcode's Release configuration),
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/// `condition` is not evaluated, and there are no effects.
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///
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/// * In `-Ounchecked` builds, `condition` is not evaluated, but the optimizer
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/// may assume that it *always* evaluates to `true`. Failure to satisfy that
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/// assumption is a serious programming error.
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///
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///
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/// - Parameter actor: the actor whose serial executor we expect to be the current executor
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@available(SwiftStdlib 5.9, *) // FIXME: use @backDeploy(before: SwiftStdlib 5.9)
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public
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func assertTaskOnActorExecutor(
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_ actor: some Actor,
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_ message: @autoclosure () -> String = String(),
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file: StaticString = #fileID, line: UInt = #line
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) {
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guard _isDebugAssertConfiguration() else {
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return
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}
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guard _taskIsCurrentExecutor(actor.unownedExecutor.executor) else {
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// TODO: offer information which executor we actually got
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// TODO: figure out a way to get the typed repr out of the unowned executor
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let msg = "Incorrect actor executor assumption; Expected '\(actor.unownedExecutor)' executor. \(message())"
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/// TODO: implement the logic in-place perhaps rather than delegating to precondition()?
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assertionFailure(msg, file: file, line: line) // short-cut so we get the exact same failure reporting semantics
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return
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}
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}
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// ==== -----------------------------------------------------------------------
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// MARK: Assume Executor
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/// A safe way to synchronously assume that the current execution context belongs to the MainActor.
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///

‎stdlib/public/core/AssertCommon.swift

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Original file line numberDiff line numberDiff line change
@@ -29,8 +29,9 @@ func _isDebugAssertConfiguration() -> Bool {
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return Int32(Builtin.assert_configuration()) == 0
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}
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32-
@usableFromInline @_transparent
33-
internal func _isReleaseAssertConfiguration() -> Bool {
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@_transparent
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public // @testable, used in _Concurrency executor preconditions
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func _isReleaseAssertConfiguration() -> Bool {
3435
// The values for the assert_configuration call are:
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// 0: Debug
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// 1: Release

‎test/Concurrency/Runtime/actor_assert_precondition_executor.swift

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// RUN: %empty-directory(%t)
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// RUN: %target-build-swift -Xfrontend -disable-availability-checking -parse-as-library %s -o %t/a.out
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// RUN: %target-codesign %t/a.out
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// RUN: %target-run %t/a.out
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// REQUIRES: executable_test
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// REQUIRES: concurrency
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// REQUIRES: concurrency_runtime
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// UNSUPPORTED: back_deployment_runtime
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// UNSUPPORTED: back_deploy_concurrency
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// UNSUPPORTED: use_os_stdlib
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// UNSUPPORTED: freestanding
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import StdlibUnittest
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func checkPreconditionMainActor() /* synchronous! */ {
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preconditionTaskOnActorExecutor(MainActor.shared)
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}
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func checkPreconditionFamousActor() /* synchronous! */ {
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preconditionTaskOnActorExecutor(FamousActor.shared)
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}
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@MainActor
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func mainActorCallCheck() {
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checkPreconditionMainActor()
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}
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@globalActor actor FamousActor: GlobalActor {
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public static let shared = FamousActor()
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func callCheckFamousActor() {
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checkPreconditionFamousActor() // ok
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}
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func callCheckMainActor() {
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checkPreconditionMainActor() // bad
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}
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}
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actor MainFriend {
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nonisolated var unownedExecutor: UnownedSerialExecutor {
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MainActor.sharedUnownedExecutor
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}
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func callCheckMainActor() {
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checkPreconditionMainActor()
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}
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}
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actor Someone {
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func callCheckMainActor() {
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checkPreconditionMainActor()
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}
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}
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@main struct Main {
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static func main() async {
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let tests = TestSuite("AssertPreconditionActorExecutor")
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if #available(SwiftStdlib 5.9, *) {
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// === MainActor --------------------------------------------------------
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tests.test("preconditionTaskOnActorExecutor(main): from 'main() async', with await") {
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await checkPreconditionMainActor()
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}
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// FIXME: calling without await from main() should also succeed, we must set the executor while we're kicking off main
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tests.test("preconditionTaskOnActorExecutor(main): from Main friend") {
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await MainFriend().callCheckMainActor()
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}
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tests.test("preconditionTaskOnActorExecutor(main): wrongly assume the main executor, from actor on other executor") {
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expectCrashLater(withMessage: "Incorrect actor executor assumption; Expected 'MainActor' executor.")
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await Someone().callCheckMainActor()
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}
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// === Global actor -----------------------------------------------------
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tests.test("preconditionTaskOnActorExecutor(main): assume FamousActor, from FamousActor") {
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await FamousActor.shared.callCheckFamousActor()
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}
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}
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await runAllTestsAsync()
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}
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}

‎test/SourceKit/Indexing/index_with_clang_module.swift

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@@ -16,6 +16,9 @@ func foo(a: FooClassDerived) {
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// CHECK: key.kind: source.lang.swift.import.module.clang
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// CHECK-NEXT: key.name: "_SwiftConcurrencyShims"
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// CHECK: key.kind: source.lang.swift.import.module.clang
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// CHECK-NEXT: key.name: "SwiftShims"
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// CHECK: key.kind: source.lang.swift.import.module.clang
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// CHECK-NEXT: key.name: "Foo"
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// CHECK-NEXT: key.filepath: "{{.*[/\\]}}Foo{{.*}}.pcm"

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