You could simply catch IndexError.

Do we need to ensure the first char is an int?

I wonder if we should raise an error or at least log that product_version could not have been guessed.

It would be very helpful if this change had test(s) which showed the expected inputs and outputs.

Please write a unit test for the new code.

It should be a bit better now. Thanks for the reviews :)

Wouldn't it be better to use a regex and return the match?

match = re.search(r'\brhel\d+', toparse)
if match:
    return match[0]

Looks like rhelX will match only very few modules in Brew (and no compose/package builds). Is that right?

@mvadkert can you reply to @lholecek's question?
I'm actually not sure about the answer.

It's not completely right, because we have to return not match, but "rhel-x" with the "-".
But I'm sure there's a similar solution :)
/me checks

+1

Commit e483b0e2 fixes this pull-request