Our team just discovered that Darwin's XCTest is not testing a test methods that are part of a test case which is a generic subclass of XCTestCase.
Those methods are displayed in the Test Navigator and can be executed manually but are not executed by Product->Tests or command line tools on CI.
On the beginning I was thinking that the problem is part of discovery tool but those test methods are displayed in the Test Navigator so maybe it's something else.
class MockGenerator {}
class CustomTestCase<T>: XCTestCase {}
class CustomTests: CustomTestCase<MockGenerator> {
func testA() throws {
XCTAssertTrue(true)
}
}