 // UNSUPPORTED: OS=wasi
 
 import StdlibUnittest
+#if _runtime(_ObjC)
+import Foundation // For NSString
+#endif
 
 let testSuiteSuffix = _isDebugAssertConfiguration() ? "_debug" : "_release"
 

    { _isFastAssertConfiguration() },
    reason: "this trap is not guaranteed to happen in -Ounchecked"))
  .code {
  var s = "abc"
  var i = s.utf16.startIndex
  i = s.utf16.index(after: i)
  i = s.utf16.index(after: i)

  i = s.unicodeScalars.index(after: i)
}

StringTraps.test("UnicodeScalarView index(before:) trap on i > endIndex")
.skip(
  .custom({ _isFastAssertConfiguration() },
  reason: "trap is not guaranteed to happen in -Ounchecked"))
.code {
  guard #available(SwiftStdlib 5.7, *) else { return }

  let long = "abcd"
  var i = long.unicodeScalars.endIndex

  let s = "abc"
  expectCrashLater()
  i = s.unicodeScalars.index(before: i)
}

#if _runtime(_ObjC)
StringTraps.test("UTF8View foreign index(after:) trap on i > endIndex")
.skip(
  .custom({ _isFastAssertConfiguration() },
  reason: "trap is not guaranteed to happen in -Ounchecked"))
.code {
  guard #available(SwiftStdlib 5.7, *) else { return }

  let long = "🐘 This is a quite large string, with lots of data"
  let short = ("🐭 I'm much smaller" as NSString) as String

  var i = long.utf8.endIndex
  expectCrashLater()
  // Note: we expect that `short` will be UTF-16 encoded here -- this trap only
  // happens on the foreign path. For native/shared strings, the UTF-8 view's
  // `index(after:)` is essentially doing a simple `i + 1`, like Array does.
  i = short.utf8.index(after: i)
}
#endif

#if _runtime(_ObjC)
StringTraps.test("UTF8View foreign index(before:) trap on i > endIndex")
.skip(
  .custom({ _isFastAssertConfiguration() },
  reason: "trap is not guaranteed to happen in -Ounchecked"))
.code {
  guard #available(SwiftStdlib 5.7, *) else { return }

  let long = "🐘 This is a quite large string, with lots of data"
  let short = ("🐭 I'm much smaller" as NSString) as String

  var i = long.utf8.endIndex
  expectCrashLater()
  // Note: we expect that `short` will be UTF-16 encoded here -- this trap only
  // happens on the foreign path. For native/shared strings, the UTF-8 view's
  // `index(before:)` is essentially doing a simple `i - 1`, like Array does.
  // (Following the unconditional i != startIndex check.)
  i = short.utf8.index(before: i)
}
#endif

#if _runtime(_ObjC)
StringTraps.test("UTF8View foreign index(after:) trap on i == endIndex")
.skip(
  .custom({ _isFastAssertConfiguration() },
  reason: "trap is not guaranteed to happen in -Ounchecked"))
.code {
  guard #available(SwiftStdlib 5.7, *) else { return }

  let s = ("🦧 The Librarian" as NSString) as String

  var i = s.utf8.endIndex
  expectCrashLater()
  // Note: we expect that `short` will be UTF-16 encoded here -- this trap only
  // happens on the foreign path. For native/shared strings, the UTF-8 view's
  // `index(after:)` is essentially doing a simple `i + 1`, like Array does.
  i = s.utf8.index(after: i)
}
#endif

#if _runtime(_ObjC)
StringTraps.test("UTF8View foreign index(before:) trap on i == startIndex")
.skip(
  .custom({ _isFastAssertConfiguration() },
  reason: "trap is not guaranteed to happen in -Ounchecked"))
.code {
  guard #available(SwiftStdlib 5.7, *) else { return }

  let s = ("🦧 The Librarian" as NSString) as String
  var i = s.utf8.startIndex
  expectCrashLater()
  i = s.utf8.index(before: i)
}
#endif

runAllTests()

