Issue with emitted values containg undefined properties

[Chris Bouchard]

I have a test like the following:

it(`should fail with a useful error message`, marbles(m => {
    const actual = of([undefined]);
    m.expect(actual).toBeObservable('--|');
}));

I expect the test to fail with a message that the observables don't match, but instead I get an error like:

TypeError: Unable to get property 'replace' of undefined or null reference
   at stringify ...

(I've cut out the stack trace because I'm using webpack). The problem seems to be that stringify in matcher.js does not check if its parameter x is undefined before attempting to format it. Simply checking for undefined and returning 'undefined' makes the test fail correctly.

This does not happen if the emitted value is actually undefined, only if it has an undefined property (or presumably if any of its inner objects do). It also does not happen for tests that pass, regardless of the emitted values.

[Nicholas Jamieson]

Thanks. This should be fixed in 2.3.1.