Is there a reason for repeating the indent_style?

Also, why not using something like [*.{json,yml}] since I believe it applies to both?

@jadb only .yml require 2 space. Json is 4 space as normal.

composer.json fo example have 4 spaces I think...

I see 2 spaces being used almost everywhere for json:

https://docs.npmjs.com/misc/coding-style

For example, bower.json is 2 spaces as well.

I noticed now composer init creates it with 4 spaces, not sure why though.

@jadb PHP's json_encode() with pretty print option indents using 4 spaces.