class ParentTestCase {
    static var allParentTests: [(String, (ParentTestCase) -> () throws -> Void)] {
        return [("testNumberIsPositive", testNumberIsPositive)]
    }

    func testNumberIsPositive() throws {
        print(createNumber())
    }

    func createNumber() -> Int {
        return 1
    }
}

class ChildTestCase: ParentTestCase {
    static var allChildTests: [(String, (ChildTestCase) -> () throws -> Void)] {
        return [("testNumberIsGreaterThan1", testNumberIsGreaterThan1),
                ("testNumberIsPositive", testNumberIsPositive)]
    }

    func testNumberIsGreaterThan1() throws {
        print(createNumber())
    }

    override func createNumber() -> Int {
        return 2
    }
}

let x = ParentTestCase()
let y = ChildTestCase()

for (name, method) in ParentTestCase.allParentTests {
    print("Calling \(name)...")
    try method(x)()
}

for (name, method) in ChildTestCase.allChildTests {
    print("Calling \(name)...")
    try method(y)()
}

 

subtype conversion in tuple and element is invalid: (ChildTestCase) -> () throws -> () to (ParentTestCase) -> () throws -> ()
0 swift 0x000000000376f838
1 swift 0x00000000037703d6
2 libpthread.so.0 0x00007fabb399b330
3 libc.so.6 0x00007fabb217dc37 gsignal + 55
4 libc.so.6 0x00007fabb2181028 abort + 328
5 swift 0x0000000001455061
6 swift 0x00000000014402b6
7 swift 0x000000000145dc96
8 swift 0x000000000145e772
9 swift 0x0000000001460ade
10 swift 0x000000000145ddc6
11 swift 0x000000000145c614
12 swift 0x000000000145c495
13 swift 0x000000000145af70
14 swift 0x000000000145a605
15 swift 0x000000000145b6c4
16 swift 0x000000000145a5f1
17 swift 0x000000000145a4c4
18 swift 0x00000000014decde
19 swift 0x000000000143e055
20 swift 0x0000000001315fbd
21 swift 0x0000000000f16de6
22 swift 0x00000000004a39a9
23 swift 0x00000000004a2775
24 swift 0x0000000000465a82
25 libc.so.6 0x00007fabb2168f45 __libc_start_main + 245
26 swift 0x000000000046365b
Stack dump:
0. Program arguments: /root/.swiftenv/versions/4.0/usr/bin/swift -frontend -c -primary-file test.swift -target x86_64-unknown-linux-gnu -disable-objc-interop -color-diagnostics -module-name test -o /tmp/test-dd9324.o
1. While walking into decl 'ChildTestCase' at test.swift:17:1
2. While walking into body of getter for allChildTests at test.swift:18:16

("testNumberIsPositive", testNumberIsPositive)]

("testNumberIsPositive", testNumberIsPositive as (ChildTestCase) -> () throws -> Void)].