XCTest+X.swift

public func XCTAssertSoon(_ expression: @autoclosure () throws -> Bool, _ message: @autoclosure () -> String = "", file: StaticString = #file, line: UInt = #line, waitTime: TimeInterval = 3) {
    let startTime = Date()
    repeat {
        let success = (try? expression()) ?? false
        if success {
            return
        }
        else {
            Thread.sleep(forTimeInterval: 1)
        }
    }
    while Date().timeIntervalSince(startTime) < waitTime
    
    XCTAssert((try? expression()) ?? false, message(), file: file, line: line)
}

extension XCUIElement {
    var existsSoon: Bool {
        return self.exists || self.waitForExistence(timeout: 3)
    }
    
    func tapSoon() {
        XCTAssert(self.existsSoon)
        self.tap()
    }
}