Using XCTest, how can one chain together multiple discrete sequences of { expectations -> wait }?

Question

The documentation for XCTest waitForExpectationsWithTimeout:handler:, states that

Only one -waitForExpectationsWithTimeout:handler: can be active at any given time, but multiple discrete sequences of { expectations -> wait } can be chained together.

However, I have no idea how to implement this, nor can I find any examples. I'm working on a class that first needs to find all available serial ports, pick the correct port and then connect to the device attached to that port. So, I'm working with at least two expectations, XCTestExpectation *expectationAllAvailablePorts and *expectationConnectedToDevice. How would I chain those two?

Answer 1

I do the following and it works.

expectation = [self expectationWithDescription:@"Testing Async Method Works!"];

[AsynClass method:parameter callbackFunction:^(BOOL callbackStatus, NSMutableArray* array) {
    [expectation fulfil];
    // whatever
}];

[self waitForExpectationsWithTimeout:5 handler:^(NSError *error) {
    if (error) {
        XCTFail(@"Expectation Failed with error: %@", error);
    }
    NSLog(@"expectation wait until handler finished ");
}];

// do it again

expectation = [self expectationWithDescription:@"Testing Async Method Works!"];

[CallBackClass method:parameter callbackFunction:^(BOOL callbackStatus, NSMutableArray* array) {
    [expectation fulfil];
    // whatever
}];

[self waitForExpectationsWithTimeout:5 handler:^(NSError *error) {
    if (error) {
        XCTFail(@"Expectation Failed with error: %@", error);
    }
    NSLog(@"expectation wait until handler finished ");
}];

Answer 2

swift

let expectation1 = //your definition
let expectation2 = //your definition

let result = XCTWaiter().wait(for: [expectation1, expectation2], timeout: 10, enforceOrder: true)

if result == .completed {
    //all expectations completed in order
}