jasmine/spec/core/SpyStrategySpec.js

describe("SpyStrategy", function() {

  it("defaults its name to unknown", function() {
    var spyStrategy = new jasmineUnderTest.SpyStrategy();

    expect(spyStrategy.identity).toEqual("unknown");
  });

  it("takes a name", function() {
    var spyStrategy = new jasmineUnderTest.SpyStrategy({name: "foo"});

    expect(spyStrategy.identity).toEqual("foo");
  });

  it("stubs an original function, if provided", function() {
    var originalFn = jasmine.createSpy("original"),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

    spyStrategy.exec();

    expect(originalFn).not.toHaveBeenCalled();
  });

  it("allows an original function to be called, passed through the params and returns it's value", function() {
    var originalFn = jasmine.createSpy("original").and.returnValue(42),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn}),
        returnValue;

    spyStrategy.callThrough();
    returnValue = spyStrategy.exec(null, ["foo"]);

    expect(originalFn).toHaveBeenCalled();
    expect(originalFn.calls.mostRecent().args).toEqual(["foo"]);
    expect(returnValue).toEqual(42);
  });

  it("can return a specified value when executed", function() {
    var originalFn = jasmine.createSpy("original"),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn}),
        returnValue;

    spyStrategy.returnValue(17);
    returnValue = spyStrategy.exec();

    expect(originalFn).not.toHaveBeenCalled();
    expect(returnValue).toEqual(17);
  });

  it("can return specified values in order specified when executed", function() {
    var originalFn = jasmine.createSpy("original"),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

    spyStrategy.returnValues('value1', 'value2', 'value3');

    expect(spyStrategy.exec()).toEqual('value1');
    expect(spyStrategy.exec()).toEqual('value2');
    expect(spyStrategy.exec()).toBe('value3');
    expect(spyStrategy.exec()).toBeUndefined();
    expect(originalFn).not.toHaveBeenCalled();
  });

  it("allows an exception to be thrown when executed", function() {
    var originalFn = jasmine.createSpy("original"),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

    spyStrategy.throwError(new TypeError("bar"));

    expect(function() { spyStrategy.exec(); }).toThrowError(TypeError, "bar");
    expect(originalFn).not.toHaveBeenCalled();
  });

  it("allows a non-Error to be thrown, wrapping it into an exception when executed", function() {
    var originalFn = jasmine.createSpy("original"),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

    spyStrategy.throwError("bar");

    expect(function() { spyStrategy.exec(); }).toThrowError(Error, "bar");
    expect(originalFn).not.toHaveBeenCalled();
  });

  it("allows a fake function to be called instead", function() {
    var originalFn = jasmine.createSpy("original"),
        fakeFn = jasmine.createSpy("fake").and.returnValue(67),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn}),
        returnValue;

    spyStrategy.callFake(fakeFn);
    returnValue = spyStrategy.exec();

    expect(originalFn).not.toHaveBeenCalled();
    expect(returnValue).toEqual(67);
  });

  it("allows a fake async function to be called instead", function(done) {
    jasmine.getEnv().requireAsyncAwait();
    var originalFn = jasmine.createSpy("original"),
        fakeFn = jasmine.createSpy("fake").and.callFake(eval("async () => { return 67; }")),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn}),
        returnValue;

    spyStrategy.callFake(fakeFn);
    spyStrategy.exec().then(function (returnValue) {
      expect(originalFn).not.toHaveBeenCalled();
      expect(fakeFn).toHaveBeenCalled();
      expect(returnValue).toEqual(67);
      done();
    }).catch(function (err) {
      done.fail(err);
    })
  });

  describe("#resolveValue", function() {
    it("allows a resolved promise to be returned", function(done) {
      jasmine.getEnv().requirePromises();

      var originalFn = jasmine.createSpy("original"),
          spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

      spyStrategy.resolveValue(37);
      spyStrategy.exec().then(function (returnValue) {
        expect(returnValue).toEqual(37);
        done();
      }).catch(done.fail);
    });

    it("fails if promises are not available", function() {
      var originalFn = jasmine.createSpy("original"),
          spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

      spyOn(jasmineUnderTest, 'getPromise');

      expect(function() {
        spyStrategy.resolveValue(37);
      }).toThrowError('resolveValue requires global Promise, or a `promiseLibrary` configured with `jasmine.getEnv().configure()`');
    });
  });

  describe("#rejectValue", function() {
    it("allows a rejected promise to be returned", function(done) {
      jasmine.getEnv().requirePromises();

      var originalFn = jasmine.createSpy("original"),
          spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

      spyStrategy.rejectValue(new Error('oops'));
      spyStrategy.exec().then(done.fail).catch(function (error) {
        expect(error).toEqual(new Error('oops'));
        done();
      }).catch(done.fail);
    });

    it("fails if promises are not available", function() {
      var originalFn = jasmine.createSpy("original"),
          spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn});

      spyOn(jasmineUnderTest, 'getPromise');

      expect(function() {
        spyStrategy.rejectValue(new Error('oops'));
      }).toThrowError('rejectValue requires global Promise, or a `promiseLibrary` configured with `jasmine.getEnv().configure()`');
    });
  });

  it("allows a custom strategy to be used", function() {
    var plan = jasmine.createSpy('custom strategy')
        .and.returnValue('custom strategy result'),
      customStrategy = jasmine.createSpy('custom strategy')
        .and.returnValue(plan),
      originalFn = jasmine.createSpy('original'),
      spyStrategy = new jasmineUnderTest.SpyStrategy({
        fn: originalFn,
        customStrategies: {
          doSomething: customStrategy
        }
      });

    spyStrategy.doSomething(1, 2, 3);
    expect(customStrategy).toHaveBeenCalledWith(1, 2, 3);
    expect(spyStrategy.exec(null, ['some', 'args']))
      .toEqual('custom strategy result');
    expect(plan).toHaveBeenCalledWith('some', 'args');
  });

  it("throws an error if a custom strategy doesn't return a function", function() {
    var originalFn = jasmine.createSpy('original'),
      spyStrategy = new jasmineUnderTest.SpyStrategy({
        fn: originalFn,
        customStrategies: {
          doSomething: function() { return 'not a function' }
        }
      });

    expect(function() { spyStrategy.doSomething(1, 2, 3) }).toThrowError('Spy strategy must return a function');
  });

  it("does not allow custom strategies to overwrite existing methods", function() {
    var spyStrategy = new jasmineUnderTest.SpyStrategy({
        fn: function() {},
        customStrategies: {
          exec: function() {}
        }
       });

    expect(spyStrategy.exec).toBe(jasmineUnderTest.SpyStrategy.prototype.exec);
  });

  it('throws an error when a non-function is passed to callFake strategy', function() {
    var originalFn = jasmine.createSpy('original'),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn}),
        invalidFakes = [5, 'foo', {}, true, false, null, void 0, new Date(), /.*/];

    spyOn(jasmineUnderTest, 'isFunction_').and.returnValue(false);
    spyOn(jasmineUnderTest, 'isAsyncFunction_').and.returnValue(false);

    expect(function () {
      spyStrategy.callFake(function() {});
    }).toThrowError(/^Argument passed to callFake should be a function, got/);

    expect(function () {
      spyStrategy.callFake(function() {});
    }).toThrowError(/^Argument passed to callFake should be a function, got/);
  });

  it("allows a return to plan stubbing after another strategy", function() {
    var originalFn = jasmine.createSpy("original"),
        fakeFn = jasmine.createSpy("fake").and.returnValue(67),
        spyStrategy = new jasmineUnderTest.SpyStrategy({fn: originalFn}),
        returnValue;

    spyStrategy.callFake(fakeFn);
    returnValue = spyStrategy.exec();

    expect(originalFn).not.toHaveBeenCalled();
    expect(returnValue).toEqual(67);

    spyStrategy.stub();
    returnValue = spyStrategy.exec();

    expect(returnValue).toEqual(void 0);
  });

  it("returns the spy after changing the strategy", function(){
    var spy = {},
        spyFn = jasmine.createSpy('spyFn').and.returnValue(spy),
        spyStrategy = new jasmineUnderTest.SpyStrategy({getSpy: spyFn});

    expect(spyStrategy.callThrough()).toBe(spy);
    expect(spyStrategy.returnValue()).toBe(spy);
    expect(spyStrategy.throwError()).toBe(spy);
    expect(spyStrategy.callFake(function() {})).toBe(spy);
    expect(spyStrategy.stub()).toBe(spy);
  });
});