(feature): FixFormatter: new formatter for printing fixed files

[ianks]

PR checklist

• New feature, bugfix, or enhancement
  • Includes tests

What changes did you make?

This PR adds a FixFormatter which take a single file, and prints the fixed contents of said file. The goal is to be able to integrate with editor plugins such as neoformat, which rely on the the formatted text being printed to stdout.

Currently, this formatter will only work when passing in a single file. I think from a practicality standpoint, this makes a lot of sense as the output will always be merged into a single stream (stdout, some file, etc), where the end user probably will not want to merge all of the files together.

Happy to any suggestions and improve this in any way you see fit!

-Ian

[palantirtech]

Thanks for your interest in palantir/tslint, @ianks! Before we can accept your pull request, you need to sign our contributor license agreement - just visit https://cla.palantir.com/ and follow the instructions. Once you sign, I'll automatically update this pull request.

[nchen63]

sorry, I thought about this more, and I don't think it will work because the fixes from different rules could overwrite each other. Our internal logic actually reloads the file after each rule applies its fixes to avoid this issue. Could you work around this by applying the fixes on a copy of the file and using that as your input?

[ianks]

@nchen63 why was this closed?

[nchen63]

The approach of using a formatter just isn't feasible given my reasons above.

[ianks]

Ok, so what would be the best way to get this feature implemented? Should we continue the discussion in #2125?

[nchen63]

sure, let me know if my idea of copying the file doesn't work for you