// RUN: %target-run-simple-swift(-Xfrontend -sil-verify-all -enable-experimental-feature ReferenceBindings)

// REQUIRES: executable_test
// REQUIRES: swift_feature_ReferenceBindings

import StdlibUnittest

defer { runAllTests() }

var tests = TestSuite("reference bindings")

var global: String = "globalName"
tests.test("global access") {
  expectEqual(global, "globalName")
  do {
    inout x = global
    expectEqual(x, "globalName")
  }
  expectEqual(global, "globalName")
}

tests.test("multiple global access exclusivity error")
  .crashOutputMatches("Simultaneous accesses to")
  .code {
    expectCrashLater()

    @inline(never)
    func test(_ x: inout String) {
      inout x = global
    }
    test(&global)
  }

tests.test("Class Instance Field Access") {
  class Klass {
    var name: String = "klassName"
  }

  let k = Klass()
  expectEqual(k.name, "klassName")
  do {
    inout x = k.name
    expectEqual(x, "klassName")
  }
  expectEqual(k.name, "klassName")
}

tests.test("Var Access") {
  var varName = "varName"
  do {
    inout x = varName
    expectEqual(x, "varName")
  }
  expectEqual(varName, "varName")

  struct S {
    var s1 = "field1"
    var s2 = "field2"
  }

  var s = S()
  expectEqual(s.s1, "field1")
  expectEqual(s.s2, "field2")
  do {
    inout x = s.s1
    expectEqual(x, "field1")
  }
  expectEqual(s.s1, "field1")
  expectEqual(s.s2, "field2")
  do {
    inout x2 = s.s2
    expectEqual(x2, "field2")
  }
  expectEqual(s.s1, "field1")
  expectEqual(s.s2, "field2")
}


tests.test("InOut Access") {
  var varName = "varName"
  func inoutTest(_ inputX: inout String) {
    expectEqual(inputX, "varName")
      inout x = inputX
    expectEqual(x, "varName")
  }
  inoutTest(&varName)
  expectEqual(varName, "varName")
}

// We use to hit a verifier error here.
tests.test("Class Use") {
  class Klass {
    var value: String = "varName"
  }

  struct S {
    var k = Klass()
    var i = 5
    mutating func x() {
      print("\(i)")
    }
  }

  var s = S()
  do {
    inout x = s.k
    expectEqual(x.value, "varName")
  }
}