Tests/BasicTests/ConditionTests.swift

/*
 This source file is part of the Swift.org open source project

 Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
 Licensed under Apache License v2.0 with Runtime Library Exception

 See http://swift.org/LICENSE.txt for license information
 See http://swift.org/CONTRIBUTORS.txt for Swift project authors
*/

import XCTest
import Foundation

import Basic

class ConditionTests: XCTestCase {
    func testSignal() {
        let condition = Condition()
        var waiting = false
        var doneWaiting = false
        let thread = Thread {
            condition.whileLocked{
                waiting = true
                condition.wait()
                doneWaiting = true
            }
        }
        thread.start()
        
        // Wait for the thread to start waiting
        while condition.whileLocked({ !waiting }) {}

        // Signal and wait for the thread to complete.
        condition.whileLocked{
            condition.signal()
        }
        thread.join()

        // Wait for the thread to complete.
        XCTAssert(doneWaiting)
    }

    func testBroadcast() {
        let condition = Condition()
        var waiting = [false, false]
        var doneWaiting = [false, false]
        let threads = [0, 1].map { i -> Thread in
            let thread = Thread {
                condition.whileLocked{
                    waiting[i] = true
                    condition.wait()
                    doneWaiting[i] = true
                }
            }
            thread.start()
            return thread
        }
        
        // Wait for each thread to start waiting.
        while condition.whileLocked({ !waiting[0] || !waiting[1] }) {}

        // Signal and wait for the thread to complete.
        condition.whileLocked{
            condition.broadcast()
        }
        threads.forEach{ $0.join() }

        // Wait for each thread to complete.
        XCTAssert(doneWaiting[0])
        XCTAssert(doneWaiting[1])
    }

    func testWaitUntil() {
        let condition = Condition()
        var waiting = false
        var doneWaiting = false

        let thread = Thread {
            condition.whileLocked{
                waiting = true
                let timeLimitReached = !condition.wait(until: Date() + 0.1)
                if timeLimitReached {
                    doneWaiting = true
                }
            }
        }
        thread.start()

        // Wait for the thread to start waiting
        while condition.whileLocked({ !waiting }) {}
        // We expect condition wait to timeout.
        thread.join()

        XCTAssert(doneWaiting)
    }

    static var allTests = [
        ("testSignal", testSignal),
        ("testBroadcast", testBroadcast),
        ("testWaitUntil", testWaitUntil),
    ]
}