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// RUN: %target-swift-emit-sil %s -verify | %FileCheck %s
func testUnreachableAfterReturn() -> Int {
var x: Int = 3
return x
x += 1 //expected-warning {{code after 'return' will never be executed}}
}
func testUnreachableAfterIfReturn(a: Bool) -> Int {
if a {
return 1
} else {
return 0
}
var _: Int = testUnreachableAfterReturn() // expected-warning {{will never be executed}}
}
func testUnreachableForAfterContinue(b: Bool) {
for _ in 0..<10 {
var y: Int = 300
y += 1
if b {
break
y += 1 // expected-warning {{code after 'break' will never be executed}}
}
continue
y -= 1 // expected-warning {{code after 'continue' will never be executed}}
}
}
func testUnreachableWhileAfterContinue(b: Bool) {
var i:Int = 0
while (i<10) {
var y: Int = 300
y += 1
if b {
break
y += 1 // expected-warning {{code after 'break' will never be executed}}
}
continue
i += 1 // expected-warning {{code after 'continue' will never be executed}}
}
}
func testBreakAndContinue() {
var m = 0
for _ in 0 ..< 10 {
m += 1
if m == 15 {
break
} else {
continue
}
m += 1 // expected-warning {{will never be executed}}
}
}
// <rdar://problem/20253447> `case let Case` without bindings incorrectly matches other cases
enum Tree {
case Leaf(Int)
case Branch(Int)
}
func testUnreachableCase1(a : Tree) {
switch a {
case let Leaf:
_ = Leaf
return
case .Branch(_): // expected-warning {{case is already handled by previous patterns; consider removing it}}
return
}
}
func testUnreachableCase2(a : Tree) {
switch a {
case let Leaf:
_ = Leaf
fallthrough
case .Branch(_): // expected-warning {{case is already handled by previous patterns; consider removing it}}
return
}
}
func testUnreachableCase3(a : Tree) {
switch a {
case _:
break
case .Branch(_): // expected-warning {{case is already handled by previous patterns; consider removing it}}
return
}
}
func testUnreachableCase4(a : Tree) {
switch a {
case .Leaf(_):
return
case .Branch(_):
return
}
}
func testUnreachableCase5(a : Tree) {
switch a {
case _:
break
default: // expected-warning {{default will never be executed}}
return
}
}
// https://github.com/apple/swift/issues/48333
func testOptionalEvaluationBreak(a : Tree) {
class C { func foo() {} }
func createOptional() -> C? { return C() }
switch a {
case _:
break
createOptional()?.foo() // expected-warning {{code after 'break' will never be executed}}
}
}
func testUnreachableAfterThrow(e: Error) throws {
throw e
return // expected-warning {{code after 'throw' will never be executed}}
}
class TestThrowInInit {
required init(e: Error) throws {
throw e // no unreachable code diagnostic for the implicit return.
}
}
// https://github.com/apple/swift/issues/48696
func f_48696() {
var bar: String? = ""
return;
bar?.append("x") // expected-warning{{code after 'return' will never be executed}}
}
func testUnreachableCatchClause() {
enum ErrorEnum: Error { case someError }
do {
throw ErrorEnum.someError
} catch let error {
print(error)
} catch ErrorEnum.someError { // expected-warning {{case will never be executed}}
print("some error")
}
}
// https://github.com/apple/swift/issues/56075
func f_56075() -> Int {
return Foo.bar
struct Foo { // no-warning
static var bar = 0
// CHECK: sil private @$s16unreachable_code7f_56075SiyF3FooL_V7fooFuncyyF : $@convention(method) (Foo) -> ()
func fooFunc() {}
}
func appendix() {} // no-warning
}
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