// RUN: %target-run-simple-swiftgyb
// REQUIRES: executable_test

// This test requires that the standard library calls ICU
// directly.  It is not specific to Linux, it is just that on
// Apple platforms we are using the NSString bridge right now.

// REQUIRES: OS=linux-gnu

import StdlibUnittest
import StdlibUnicodeUnittest

func assertASCIIRepresentationIfPossible(_ s: String) {
  for us in s.unicodeScalars {
    if !us.isASCII {
      return
    }
  }
  precondition(s._core.isASCII)
}

func forceUTF16Representation(_ s: String) -> String {
  var s = s
  s += "\u{fffd}"
  s.removeSubrange(s.index(before: s.endIndex)..<s.endIndex)
  precondition(!s._core.isASCII)
  return s
}

func calculateSortOrder(_ tests: inout [StringComparisonTest]) {
  tests.sort {
    collationElements(
      $0.collationElements,
      areLessThan: $1.collationElements
    )
  }

  tests[0].order = 0
  for i in tests.indices.dropFirst() {
    if collationElements(
      tests[i - 1].collationElements,
      areLessThan: tests[i].collationElements
    ) {
      tests[i].order = tests[i - 1].order! + 1
    } else {
      tests[i].order = tests[i - 1].order!
    }
  }
}

func checkStringHashableComparable(
  _ tests: [StringComparisonTest],
  stackTrace: SourceLocStack = SourceLocStack(),
  file: String = #file, line: UInt = #line
) {
  var tests = tests
  calculateSortOrder(&tests)

  func comparisonOracle(_ i: Int, _ j: Int) -> ExpectedComparisonResult {
    return tests[i].order! <=> tests[j].order!
  }

  checkHashable(
    tests.map { $0.string },
    equalityOracle: { comparisonOracle($0, $1).isEQ() },
    stackTrace: stackTrace.pushIf(true, file: file, line: line))

  checkComparable(
    tests.map { $0.string },
    oracle: comparisonOracle,
    stackTrace: stackTrace.pushIf(true, file: file, line: line))
}

var StringTests = TestSuite("StringTests")

StringTests.test("StringComparisonTest.allTests: tests are in ASCII representation")
  .forEach(in: StringComparisonTest.allTests) {
  test in
  assertASCIIRepresentationIfPossible(test.string)
}

StringTests.test("Comparable") {
  let allTestsInUTF16Representation = StringComparisonTest.allTests.map {
    test -> StringComparisonTest in
    return StringComparisonTest(
      forceUTF16Representation(test.string),
      test.collationElements,
      sourceLocation: SourceLoc(
        test.loc.file,
        test.loc.line,
        comment: (test.loc.comment ?? "") + "\nin Unicode representation"))
  }
  checkStringHashableComparable(StringComparisonTest.allTests + allTestsInUTF16Representation)
}

runAllTests()