Add support for '# gd-formatter:disable' and '# gd-formatter:enable'.

[discordier]

Implements #238.

Please check if the PR fulfills these requirements:

• The commit message follows our guidelines.
• For bug fixes and features:
  • You tested the changes.

Related issue (if applicable): #238

What kind of change does this PR introduce?

Adds support for special comments: # gd-formatter:disable and # gd-formatter:enable

Does this PR introduce a breaking change?

I don't think so.

[NathanLovato]

Thank you very much for the help! That's much appreciated.

The general of swapping the region with a placeholder is the way to go.

I went ahead and made some changes on the preprocessing side that actually I probably shouldn't have (As we add more to the program, I'm getting into a mindset of starting to write it a bit better, though writing it well will involve getting rid of topiary, in which case we won't need these ~hacky pre and post processing steps).

Practically speaking the changes:

• Make the check lenient so it ignores whitespace.
• Change the marker to turn the formatter on or off to just fmt:on or fmt:off`, which is what the black formatter uses (Python's formatter).

The second point I'm really not attached to, I just picked something used by a popular formatter that's concise to make it a bit more convenient to type.

I quickly checked what other formatters used in case there was some standard and it seems to be different and a bit arbitrary, depending on the formatter.

If you have any feedback on this, please let me know and otherwise I'll merge the change

[discordier]

Sorry for getting back to this that late been pretty busy weeks for me.
Merge as you wish, in the end you're the repository owner and I'm happy to get that functionality in at all.

However, I am unsure why you changed the second block in the test (437ce1b#diff-c9e22f75481da3de6f68e14c296c1d9f98e88e551780e58d8de706662f22677cL14).
The intention was to ensure that whitespace indention corrected.
Is this beyond the test?

[NathanLovato]

Thanks. I just reintroduced the indents. While working on it, I thought testing for any formatting change, no matter how small, would validate whether a given region is touched by the formatter or not. So having the indents or not didn't make a difference, but it's okay to have them too.

And I shouldn't have removed them in the first place.

Thank you very much for taking the time to contribute! And no worries about being busy or any delay, I perfectly understand.