prefer-single-boolean-return.test.ts

/*
 * eslint-plugin-sonarjs
 * Copyright (C) 2018-2021 SonarSource SA
 * mailto:info AT sonarsource DOT com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
import { ruleTester } from '../rule-tester';
import rule = require('../../src/rules/prefer-single-boolean-return');

ruleTester.run('prefer-single-boolean-return', rule, {
  valid: [
    {
      code: `
        function foo() {
          if (something) {
            return true;
          } else if (something) {
            return false;
          } else {
            return true;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            return x;
          } else {
            return false;
          }
        }
      `,
    },
    {
      code: `
        function foo(y) {
          if (something) {
            return true;
          } else {
            return foo;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            doSomething();
          } else {
            return true;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            doSomething();
            return true;
          } else {
            return false;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            return;
          } else {
            return true;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            return true;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            return foo(true);
          } else {
            return foo(false);
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            var x;
          } else {
            return false;
          }
        }
      `,
    },
    {
      code: `
        function foo() {
          if (something) {
            function f() {}
            return false;
          } else {
            return true;
          }
        }
      `,
    },
  ],
  invalid: [
    {
      code: `
        function foo() {
          if (something) {
            return true;
          } else {
            return false;
          }

          if (something) {
            return false;
          } else {
            return true;
          }

          if (something) return true;
          else return false;

          if (something) {
            return true;
          } else {
            return true;
          }
        }
      `,
      errors: [
        {
          messageId: 'replaceIfThenElseByReturn',
          line: 3,
          column: 11,
          endLine: 7,
          endColumn: 12,
        },
        { messageId: 'replaceIfThenElseByReturn', line: 9, column: 11, endLine: 13, endColumn: 12 },
        {
          messageId: 'replaceIfThenElseByReturn',
          line: 15,
          column: 11,
          endLine: 16,
          endColumn: 29,
        },
        {
          messageId: 'replaceIfThenElseByReturn',
          line: 18,
          column: 11,
          endLine: 22,
          endColumn: 12,
        },
      ],
    },
    {
      code: `
        function fn() {
          if (foo) {
            if (something) {
              return true
            }
            return false
          }

          if (bar) {
            if (something) {
              return false
            }
            return true
          }

          if (baz) {
            if (something) {
              return false
            }
          }
        }
      `,
      errors: [
        {
          messageId: 'replaceIfThenElseByReturn',
          line: 4,
          column: 13,
          endLine: 6,
          endColumn: 14,
        },
        {
          messageId: 'replaceIfThenElseByReturn',
          line: 11,
          column: 13,
          endLine: 13,
          endColumn: 14,
        },
      ],
    },
    {
      code: `
function foo() {
  if (bar()) {
    if (baz()) {
      return true;
    } else {
      return false;
    }
  }
  return qux();
}`,
      errors: [
        {
          messageId: 'replaceIfThenElseByReturn',
          suggestions: [
            {
              messageId: 'suggestIfThenElseReplacement',
              output: `
function foo() {
  if (bar()) {
    return baz();
  }
  return qux();
}`,
            },
          ],
        },
      ],
    },
    {
      code: `
function foo() {
  if (bar()) {
    if (baz()) {
      return true;
    }
    return false;
  }
  return qux();
}`,
      errors: [
        {
          messageId: 'replaceIfThenElseByReturn',
          suggestions: [
            {
              messageId: 'suggestIfThenElseReplacement',
              output: `
function foo() {
  if (bar()) {
    return baz();
  }
  return qux();
}`,
            },
          ],
        },
      ],
    },
  ],
});