old_contents: /**
   * The MIT License (MIT)
   *
   * Copyright (c) 2014-2017 Mickael Jeanroy
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  import {toBeInstanceOf} from 'src/core/matchers/to-be-instance-of.js';
  
  describe('toBeInstanceOf', () => {
    let Klass;
  
    beforeEach(() => {
      // eslint-disable-next-line
      Klass = class Klass {
        // eslint-disable-next-line
        constructor() {}
      };
    });
  
    it('should pass if value is an instance of given class', () => {
      const actual = new Klass();
      const result = toBeInstanceOf({actual}, Klass);
      expect(result).toEqual({
        pass: true,
        message: 'Expect Klass({  }) {{not}} to be an instance of Function',
      });
    });
  
    it('should not pass if value is not an instance of given class', () => {
      const actual = '';
      const result = toBeInstanceOf({actual}, Klass);
      expect(result).toEqual({
        pass: false,
        message: `Expect '' {{not}} to be an instance of Function`,
      });
    });
  });
  
new_contents: /**
   * The MIT License (MIT)
   *
   * Copyright (c) 2014-2017 Mickael Jeanroy
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  import {Klass} from '../fixtures/klass.js';
  import {toBeInstanceOf} from 'src/core/matchers/to-be-instance-of.js';
  
  describe('toBeInstanceOf', () => {
    it('should pass if value is an instance of given class', () => {
      const actual = new Klass();
      const result = toBeInstanceOf({actual}, Klass);
      expect(result).toEqual({
        pass: true,
        message: 'Expect Klass({ id: 0 }) {{not}} to be an instance of Function',
      });
    });
  
    it('should not pass if value is not an instance of given class', () => {
      const actual = '';
      const result = toBeInstanceOf({actual}, Klass);
      expect(result).toEqual({
        pass: false,
        message: `Expect '' {{not}} to be an instance of Function`,
      });
    });
  });
  
subject: use klass fixture