tests/compiler/dart2js/type_inference_switch_test.dart

// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import "package:async_helper/async_helper.dart";
import "package:expect/expect.dart";
import 'compiler_helper.dart';
import 'type_mask_test_helper.dart';

import 'dart:async';

const String TEST1 = r"""
foo(int x) {
  var a = "one";
  switch (x) {
    case 1:
      a = "two";
      break;
    case 2:
      break;
  }

  return a;
}

main() {
  foo(new DateTime.now().millisecondsSinceEpoch);
}
""";

const String TEST2 = r"""
foo(int x) {
  var a;
  switch (x) {
    case 1:
      a = "two";
      break;
    case 2:
      break;
  }

  return a;
}

main() {
  foo(new DateTime.now().millisecondsSinceEpoch);
}
""";

const String TEST3 = r"""
foo(int x) {
  var a;
  switch (x) {
    case 1:
      a = 1;
    case 2:  // illegal fall through
      a = 2;
      break;
  }

  return a;
}

main() {
  foo(new DateTime.now().millisecondsSinceEpoch);
}
""";

const String TEST4 = r"""
foo(int x) {
  var a;
  switch (x) {
    case 1:
      a = 1;
    case 2:  // illegal fall through
      a = 2;
      break;
    default:
      a = 0;
  }

  return a;
}

main() {
  foo(new DateTime.now().millisecondsSinceEpoch);
}
""";

const String TEST5 = r"""
foo(int x) {
  var a;
  switch (x) {
    case 1:
      a = 1;
      break;
    case 2:
      a = 2;
      break;
    default:
  }

  return a;
}

main() {
  foo(new DateTime.now().millisecondsSinceEpoch);
}
""";

const String TEST6 = r"""
foo(int x) {
  var a;
  do {  // add extra locals scope
    switch (x) {
      case 1:
        a = 1;
        break;
      case 2:
        a = 2;
        break;
    }
  } while (false);

  return a;
}

main() {
  foo(new DateTime.now().millisecondsSinceEpoch);
}
""";

Future runTest(String test, checker) {
  Uri uri = new Uri(scheme: 'source');
  var compiler = compilerFor(test, uri);
  return compiler.run(uri).then((_) {
    var typesInferrer = compiler.globalInference.typesInferrerInternal;
    var closedWorld = typesInferrer.closedWorld;
    var commonMasks = closedWorld.commonMasks;

    checkTypeOf(String name, TypeMask type) {
      var element = findElement(compiler, name);
      var mask = typesInferrer.getReturnTypeOfMember(element);
      Expect.equals(type, simplify(mask, closedWorld));
    }

    checker(commonMasks, checkTypeOf);
  });
}

main() {
  asyncTest(() async {
    await runTest(TEST1, (t, c) => c("foo", t.stringType));
    await runTest(TEST2, (t, c) => c("foo", t.stringType.nullable()));
    await runTest(TEST3, (t, c) => c("foo", t.uint31Type.nullable()));
    await runTest(TEST4, (t, c) => c("foo", t.uint31Type));
    await runTest(TEST5, (t, c) => c("foo", t.uint31Type.nullable()));
    await runTest(TEST6, (t, c) => c("foo", t.uint31Type.nullable()));
  });
}