javascript - 如何正确使用createSpyObj

我正在尝试测试getDatabase版本函数是否会将查询传递给getDatabase调用的getQueryResult（）中的executeQuery函数。
代码如下：

`

var RequestHandler = function () {
  this.getQueryResult = function (sQuery) {
    this.checkConnection();
    try {
        return this.conn.executeQuery.apply(this.conn, arguments);
      } catch (err) {
        this.conn.close();
        this.conn = null;
        throw "unexpected error, please check application trace files for more information";
      }
  };
  this.getDatabaseVersion = function() {
    var query = "select top 1 VERSION from M_DATABASE";
    return this.getQueryResult(query)[0].VERSION;
  };
}

`

我写的测试用例：

`

var RHandler = $.import("sap.hana.graph.viewer.XS_Backend.js.lib", "RequestHandler").RequestHandler;

describe ("getDatabaseVersion Tests", function (){
    var rHandler = null;
    var getQueryResult = jasmine.createSpyObj('getQueryResult', ['conn', 'executeQuery', 'close']);
    var conn = jasmine.createSpyObj('conn', ['executeQuery', 'close']);

    beforeEach(function() {
        rHandler = new RHandler();
        rHandler.openConnection();
    });

    function getAllQueries() {
        return getQueryResult.conn.executeQuery.calls.allArgs().join(':::');
     }

    it('should return the databaseVersion and match the query sent to getQueryResult', function() {
        rHandler.getDatabaseVersion();
        expect(rHandler.getDatabaseVersion()).toEqual("2.00.030.00.1502184660");
        expect(getAllQueries()).toEqual(/select top 1 VERSION from M_DATABASE/i);
    });
});

`
但这根本不起作用。我走错路了。谁能指导我或让我知道我做错了什么。

最佳答案

您需要这样的东西：

var RHandler = $.import("sap.hana.graph.viewer.XS_Backend.js.lib", "RequestHandler").RequestHandler;

describe('RequestHandler', () => {
  let rHandler = null;
  let connection = null

  beforeEach(() => {
    connection = jasmine.createSpyObj('conn', ['executeQuery', 'close'])

    rHandler = new RHandler();
    rHandler.conn = connection;
  });

  describe('getQueryResult', () => {
    beforeEach(() => {
      spyOn(rHandler, 'checkConnection');
    });

    it('should check connection', () => {
      rHandler.getQueryResult();

      expect(rHandler.checkConnection).toHaveBeenCalled();
    });

    it('should execute query', () => {
      connection.executeQuery.and.returnValue('foo');

      const actual = rHandler.getQueryResult('bar', 'baz');

      // toHaveBeenCalledWithContext
      // https://www.npmjs.com/package/jasmine-spy-matchers
      expect(connection.executeQuery).toHaveBeenCalledWithContext(connection, 'bar', 'baz');
      // or default toHaveBeenCalledWith
      expect(connection.executeQuery).toHaveBeenCalledWith('bar', 'baz');

      expect(actual).toBe('foo');
    });

    it('should throw error', () => {
      connection.executeQuery.and.throwError(new Error('some error message'));

      expect(() => {
        rHandler.getQueryResult('bar', 'baz');
      }).toThrow('unexpected error, please check application trace files for more information');
      expect(rHandler.conn).toBe(null);

    });
  });

  describe('getDatabaseVersion', () => {
    it('should return version', () => {
      spyOn(rHandler, 'getQueryResult').and.returnValue([{VERSION: '2.00.030.00.1502184660'}])

      const actual = rHandler.getDatabaseVersion();

      expect(rHandler.getQueryResult).toHaveBeenCalledWith('select top 1 VERSION from M_DATABASE')
      expect(actual).toBe('2.00.030.00.1502184660');
    });
  });
});