Implement this protocol if you need to check whether the application is running in an XCTest context.

XCTestProtocol+IsRunning.swift

// Created by Nedrow, David E on 2018-11-03.
// Attribution 4.0 International (CC 4.0), see bottom.

import Foundation

/// Implement this protocol if you need to check whether the application is running in an XCTest context.
/// Default implementations are provided.
/// By their nature, these test–related queries can't themselves be exhaustively unit tested.
protocol XCTestProtocol {
    /// Used to determine if the app is running in an XCTest context.
    var isRunningXCTest: Bool { get }

    /// Used to determine if the app is running in an XCUITest context.
    var isRunningXCUITest: Bool { get }
}

extension XCTestProtocol {
    var isRunningXCTest: Bool {
        return NSClassFromString("XCTest") != nil
    }

    var isRunningXCUITest: Bool {
        return NSClassFromString("XCUITest") != nil
    }
}

extension NSObject: XCTestProtocol {}

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