2 consecutive 'when(...).thenTrow(...)' expectations crashes

[luca1226]

The Mocha test that shows the crash

   it('should not crash', function () {
      const mock = td.func();

      // 1st expectation: a generic one
      td.when(mock(td.matchers.anything())).thenThrow(new Error('1st expectation'));

      // 2nd expectation:  a more specific one
      // => IT CRASH (the 1st expectation is executed when defining this one!!!)
      td.when(mock(400)).thenThrow(new Error('2nd expectation'));
   });

Issue

The 2nd expectation crashes because the 1st expectation is executed when defining the 2nd.

We had seen that this behavior correspond to this note: "Note that because rehearsal calls invoke the test double function, it's possible to configure a thenThrow stubbing and then accidentally trigger it when you attempt to configure subsequent stubbings or verifications. In these cases, you'll need to work around it by re-ordering your configurations or catch'ing the error."

Is it possible to add an option that prevent to invoke the test double function when configuring a subsequent one?

Environment

• mocha
• node -v output: 11.2.0
• npm -v (or yarn --version) output: 6.5.0
• npm ls testdouble (or yarn list testdouble) version: 3.9.3

[searls]

As you pointed out from having read the note above, what the above code does is not yet supported by the library. I imagine what would be needed is some kind of td.disable(someFunc) API that allowed calls to be stubbed/verified without inadvertently invoking the prior stubbings of someFunc, followed by a td.enable(someFunc) API to enable it.

This would be a pretty significant code change. I'm open to it if it doesn't add a large maintenance burden, but I don't think this is a common enough case for me to invest the time to implement it.

What I'd do in your shoes is just do a single stubbing with a custom stubbing thenDo:

td.when(mock(), {ignoreExtraArgs: true}).thenDo(code => {
  if (code === 400) {
    throw new Error('2nd expectation')
  } else {
    throw new Error('1st expectation')
  } 
});

[luca1226]

Yes, thanks for your reply, you are right,