istanbul version 0.3.17 breaks CI, because console.error()

[viktordavidovich]

Istanbul version 0.3.17 breaks CI, namely TFS build, because inside lib/collector.js
line 164 we have next code:

            if (cache.hasMappings()) {
                console.error('Post-processing using source maps');
                t = cache.transformer();
            }

Build breaks, because error exists. This is absolutely wrong, because post-processing using source maps is not error.
I've investigated, that inside newest version of Istanbul - everything is fine and console.log, console.error are not existing already there.

Just note, DON"T PUSH DEV TOOLS TO THE PRODUCTION CODE!
You can break somebodies build 👍

[fizker]

I would rather say that your CI setup is incorrect, if data on stderr breaks it. You should listen to exit codes instead.

Many *nix utilities (which is the inspiration for a lot of node tools) are using stderr as progress updates and the like. Take curl for example, where the data you are downloading goes to stdout and the progress updates go to stderr.

[mpalomas]

Unfortunately some (bad?) CI such as TFS have no setting for this: it's just the default behavior.

The workaround I use (for other tool such as Git) is to redirect stderr to stdout hoping it won't break anything. And soon a better workaround: just don't use TFS