How to Try Catch in CodeceptJS

Question

I'm doing this in my page object:

try{
    I.selectOption(this.SELECT, this.OPTION);
}
catch(error){
    I.say('Option missing, but thats sometimes expected ' + error);
}

But it still fails the test when the locator doesn't match an option element.

I want to catch and continue the test, without failing.

UPDATE:

It looks like it depends on what's in the try block.

If I put an assertion there, like I.see('something'); Then the catch block is not skipped. But non-assertions in the try block, like I.selectOption('something') throw errors which are not caught by the catch.

Derrik

This sounds strange "Option missing, but thats sometimes expected". But since you catch, this should not fail? – Motta

@lorenz, that's just an arbitrary string for the error log. I could pass 'ABCD' in there. But I don't think that's causing my catch block to be skipped. – Derrik

@PatMeeker were you ever able to figure out a solution or workaround? I'm hitting the same problem. Some thoughts, though: (1) Since I.* functions usually return promises, you need to put await before the I.selectOption call in order for the failure to be caught by the catch. (2) I have a hunch that this is because CodeceptJS uses a global promise chain. So the internal global promise fails if the I.* fails, regardless of whether it's caught. – Congress

@drmercer unfortunately no. In my case, it was possible to pass contextual information to my method which I used to conditionally select the option, which wasnt as clean looking as my lazy approach above - to try selecting first and then react. Anyway, I suppose another approach might be to use JS Executor, and duplicate the functionality of whichever non-assertion methods you need into your own custom JS functions, if you REALLY want to make this flow work. – Derrik

Answer 1

Try-catch should be performed on a promise chain. I think you can get it this way:

I.selectOption(this.SELECT, this.OPTION).catch(() => I.say(''));

Extremist

I'm actually seeing the log from I.say() when I try your way, so that's an improvement. The catch block was not skipped. However, the exception was not caught. It still failed my test.... – Derrik

As with my original code, you answer also works as expected when the error is thrown from an assertion like I.see(), but still doesn't work with I.selectOption() – Derrik

Answer 2

I.selectOption(this.SELECT, this.OPTION)
.then(() => I.say('try block'))
.catch(() => I.say('catch block'));

Flimsy

This answer could be improved a lot by giving an explanation as to why this works – Transmittal