SE-0176 の理解を確認するための例題集です

SE0176Tests.swift

// 問題: コンパイルエラーもしくは実行時警告になる testX 関数をすべて答えてください。

import XCTest


class SE0176PlaygroundTests: XCTestCase {
    func test1() {
        struct ExampleStruct {
            mutating func assignedBy(_ block: () -> ExampleStruct) {
                self = block()
            }
        }

        var x = ExampleStruct()
        x.assignedBy { ExampleStruct() }
    }


    func test2() {
        struct ExampleStruct {
            mutating func assignedBy(_ block: () -> ExampleStruct) {
                self = block()
            }
        }

        var x = ExampleStruct()
        x.assignedBy { x }
    }


    func test3() {
        struct ExampleStruct {
            mutating func assignedBy(_ block: (inout ExampleStruct) -> Void) {
                block(&self)
            }
        }

        var x = ExampleStruct()
        x.assignedBy { y in y = x }
    }


    func test4() {
        struct ExampleStruct {
            var property: String?

            mutating func assignedBy(_ block: () -> String?) {
                self.property = block()
            }
        }

        var x = ExampleStruct()
        x.assignedBy { "Example" }
    }


    func test5() {
        struct ExampleStruct {
            var property: String?

            mutating func assignedBy(_ block: () -> String?) {
                self.property = block()
            }
        }

        var x = ExampleStruct()
        x.assignedBy { x.property }
    }


    func test6() {
        var x = 0
        x = { x + 1 }()
    }


    func test7() {
        class ExampleClass {
            var property: ExampleClass?

            func assignedBy(_ block: () -> ExampleClass?) {
                self.property = block()
            }
        }

        let x = ExampleClass()
        x.assignedBy { x }
    }


    func test8() {
        class ExampleClass {
            var property: ExampleClass?

            func assignedBy(_ block: (inout ExampleClass?) -> Void) {
                block(&self.property)
            }
        }

        let x = ExampleClass()
        x.assignedBy { y in y = x }
    }


    func test9() {
        var global = 0

        func swapGlobal(with another: Int) {
            global = another
        }

        swapGlobal(with: global)
    }


    func test10() {
        var global = 0

        func assignGlobal(to another: inout Int) {
            another = global
        }

        assignGlobal(to: &global)
    }


    func test11() {
        var global = 0

        func swapGlobal(with another: inout Int) {
            global = another
        }

        swapGlobal(with: &global)
    }


    func test12() {
        class ExampleClass {
            var property: Int?

            func doSomething(_ x: UnsafeMutableRawPointer) {
                print(x)
            }
        }

        var x = ExampleClass()
        x.doSomething(&x)
    }


    func test13() {
        class ExampleClass {
            var property: Int?

            func doSomething(_ x: UnsafeMutableRawPointer) {
                print(x == &self.property)
            }
        }

        var x = ExampleClass()
        x.doSomething(&x.property)
    }
}

// 答えは https://gist.github.com/Kuniwak/a32883a62a37bf72f351fa3dc9c5aac7 で確認！