Checking received calls seems to be off at times

[sluebbert]

I seem to be running into an oddity when asserting that calls were made. The received method seems to be thrown off somehow based on the stripped down test shown below.

import { Substitute, Arg } from '@fluffy-spoon/substitute';

class Transaction
{
	public Id: number;
	public Description: string;

	constructor(id: number, description: string)
	{
		this.Id = id;
		this.Description = description;
	}
}

interface IDataAccess
{
	insertTransaction(transaction: Transaction): void;
	updateTransaction(transaction: Transaction): void;
}

class Manager
{
	private dataAccess: IDataAccess;

	constructor(dataAccess: IDataAccess)
	{
		this.dataAccess = dataAccess;
	}

	public run()
	{
		this.dataAccess.insertTransaction(new Transaction(1, 'milk'));
		this.dataAccess.updateTransaction(new Transaction(2, 'gas')); // Commenting out this line will cause the test to pass
	}
}

describe('Test', function()
{
	it('Tests', () =>
	{
		var dataAccess = Substitute.for<IDataAccess>();

		var manager = new Manager(dataAccess);
		manager.run();

		dataAccess.received().insertTransaction(Arg.is(x => x.Description == 'milk'));
	});
});

Running my test fails with the unexpected message:

$ ./node_modules/mocha/bin/mocha test.ts --require ts-node/register


  Test
    1) Tests


  0 passing (18ms)
  1 failing

  1) Test
       Tests:
     Error: Expected 1 or more calls to the method updateTransaction with arguments [Argument {
  description:
   "{predicate function (x) { return x.Description == 'milk'; }}",
  matchingFunction: [Function] }], but received none of such calls.
All calls received to method updateTransaction:
-> call with arguments [Transaction { Id: 2, Description: 'gas' }]
      at InitialState.assertCallCountMatchesExpectations (node_modules/@fluffy-spoon/substitute/src/states/InitialState.ts:46:15)
      at FunctionState.apply (node_modules/@fluffy-spoon/substitute/src/states/FunctionState.ts:48:30)
      at Context.apply (node_modules/@fluffy-spoon/substitute/src/Context.ts:45:28)
      at Object.apply (node_modules/@fluffy-spoon/substitute/src/Context.ts:19:29)
      at Context.<anonymous> (test.ts:48:25)
      at processImmediate (internal/timers.js:443:21)

The error message is complaining about the method updateTransaction, even though I only stated that I am interested in asserting that insertTransaction was called. It does show the correct context of what really happened at runtime though, just with the wrong method.

[taylorn16]

I am experiencing the same issue. In my case it looks like this

this.connection.start().then(() => this.connectionStarted$.next());
this.connection.onclose(() => this.connectionClosed$.next()); // commenting this line out makes the substitute behave normally

It seems a Substitute can't handle tracking more than one method being called on it during a test case?

[DanielSiepmann]

The issue occurs once you call two methods of a mocked object, and at least one received to not the last called methods afterwards. As only state of last called method is known.

As far as I understood:
The reason is, once a method is called on the mock, a new state is generated and replaces any existing state. Therefore it's not possible to keep track of multiple methods within one mock.

A failing test can be found here: https://github.com/DanielSiepmann/FluffySpoon.JavaScript.Testing.Faking/blob/bugfix/45-received-off/spec/issues/45.test.ts

The following fixes the issue, but of courses creates a lot more issues:

 --- a/src/Context.ts
 +++ b/src/Context.ts
 @@ -29,14 +29,14 @@ export class Context {
  
          this._rootProxy = new Proxy(() => { }, {
              apply: (_target, _this, args) => {
 -                return this.initialState.apply(this, args);
 +                return this._state.apply(this, args);
              },
              set: (_target, property, value) => {
 -                this.initialState.set(this, property, value);
 +                this._state.set(this, property, value);
                  return true;
              },
              get: (_target, property) => {
 -                return this.initialState.get(this, property);
 +                return this._state.get(this, property);
              }
          });
      }

[ffMathy]

@DanielSiepmann I see you made a repo for adding the broken test. Can you open a PR as well?

[Ilham-Habibullin]

So this issue is fixed now, after merging this pr #70

[ffMathy]

Thanks!