Line breaks immediately followed by ANSI escapes are swallowed

[bruderstein]

Using unexpected, and the new ANSI escape sequence parsing in wallaby (issue #237), wallaby displays the full colour error message.

However, when a newline is immediately followed by an escape code, the newline is swallowed.

Compare:

with the same test run on the console (unexpected is actually intellegent about the line breaks, so this is on a narrower console, if the console is wider, there's just a space, not sure if that has something to do with it, but the mock tests in the demo below would suggest not)

I've mocked out the UnexpectedError object to try and work out exactly when they're swallowed, and it appears to be when an escape code immediately follows the new line.

A demo is at bruderstein/wallaby-ansi-parser

One "real" test is included, where the difference between running npm test in the console and running it in wallaby can be seen.

3 small "mock" tests that only really work in wallaby also show the difference a single space makes following the line break.

   it('shows line breaks when lines begin with letter', function () {
       throw new UnexpectedError('\x1b[32mLine one\nLine two\x1b[39m');
   });

    it('swallows line breaks when lines begin with ansi code', function () {
        throw new UnexpectedError('\x1b[32mLine one\nLine two\x1b[39m\n\x1b[31mLine 3\x1b[39m');
    });

    it('a simple space is enough to keep the line break', function () {
        throw new UnexpectedError('\x1b[32mLine one\nLine two\x1b[39m\n \x1b[31mLine 3\x1b[39m');
    });

Wallaby IntelliJ plugin 1.0.28
Wallaby core 1.0.104
WebStorm 11 (142.4148), Linux

Thank you :)

[ArtemGovorov]

Thanks a lot for the demo repo and the analysis on when exactly the issue is reproduced!
It's now fixed in Wallaby IntelliJ plugin v1.0.29.

[bruderstein]

Wow, thanks!