Report to file.

[flaviojs]

I'd like to have an option to write the eslint report to file in the format specified by formatter.

I want to have Jenkins pick it up and process it (in checkstyle format).
For console output the amount of warnings and errors is enough for me (not an issue, I'm not picky about this).

[IanVS]

That seems like a reasonable request. Would you like to try implementing it and submitting a PR?

[flaviojs]

There are so many ways this could be implemented that I'm unsure of what to do in a PR...

A lazy way to implement this would be to allow overriding the whole reporting logic:

var options = {
  // Replaces reporting logic.
  reporter: function (p, opts, report) {
    // Only contextName, timeout, and slow are used before this function is called.
    // hmm, maybe fallback to the original reporter if a specific value is returned?
  }
}

Another way would be to allow multiple formatters and introduce formatter options:

var options = {
  formatter: [
    // Default report to console.
    'stylish',
    // Always output to file.
    { formatter: 'checkstyle', file: 'lint-report.xml', always: true }
  ]
}

And many other alternatives... I don't know what kind of style you're aiming for so no idea what would be appropriate.