sdk/pkg/compiler/test/codegen/constant_folding_test.dart

// Copyright (c) 2012, 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.

// @dart = 2.7
// Test constant folding on numbers.

import 'package:expect/expect.dart';
import 'package:async_helper/async_helper.dart';
import '../helpers/compiler_helper.dart';

const String NUMBER_FOLDING = """
void main() {
  var a = 4;
  var b = 3;
  print(a + b);
}
""";

const String NEGATIVE_NUMBER_FOLDING = """
void main() {
  var a = 4;
  var b = -3;
  print(a + b);
}
""";

const String NULL_EQUALS_FOLDING = """
foo(a, b, c, d) {
  if (a == null) return 1;
  if (null == b) return 2;
  if (4 == c) return 3;
  if ("foo" == d) return 3;
}
""";

const String LIST_LENGTH_FOLDING = """
foo() {
  return const [1, 2, 3].length;
}
""";

const String STRING_LENGTH_FOLDING = """
foo() {
  return '123'.length;
}
""";

const String LIST_INDEX_FOLDING = """
foo() {
  return const [1, 2, 3][0];
}
""";

const String RANGE_ERROR_INDEX_FOLDING = """
foo() {
  return [1][1];
}
""";

main() {
  runTests() async {
    await compileAndMatch(NUMBER_FOLDING, 'main', new RegExp(r"print\(7\)"));
    await compileAndMatch(
        NEGATIVE_NUMBER_FOLDING, 'main', new RegExp(r"print\(1\)"));
    await compile(NULL_EQUALS_FOLDING, entry: 'foo', check: (String generated) {
      RegExp regexp = new RegExp(r'a == null');
      Expect.isTrue(regexp.hasMatch(generated), 'No match found for ${regexp}');

      regexp = new RegExp(r'b == null');
      Expect.isTrue(regexp.hasMatch(generated), 'No match found for ${regexp}');

      regexp = new RegExp(r'4 === c');
      Expect.isTrue(regexp.hasMatch(generated), 'No match found for ${regexp}');

      regexp = new RegExp('"foo" === d');
      Expect.isTrue(regexp.hasMatch(generated), 'No match found for ${regexp}');
    });
    await compileAndMatch(LIST_LENGTH_FOLDING, 'foo', new RegExp(r"return 3"));
    await compileAndMatch(LIST_INDEX_FOLDING, 'foo', new RegExp(r"return 1"));
    await compileAndDoNotMatch(LIST_INDEX_FOLDING, 'foo', new RegExp(r"ioore"));
    await compileAndMatch(
        STRING_LENGTH_FOLDING, 'foo', new RegExp(r"return 3"));
    await compileAndMatch(
        RANGE_ERROR_INDEX_FOLDING, 'foo', new RegExp(r"ioore"));
  }

  asyncTest(() async {
    print('--test from kernel------------------------------------------------');
    await runTests();
  });
}