Add .editorconfig

[silvanshade]

This PR adds a basic EditorConfig file.

[silvanshade]

It might be a good idea to add a separate section for [*.c] files and perhaps others if necessary.

[bjorn3]

Why 2?

[silvanshade]

No particular reason, just seems to be a popular choice. Some of the .c files seem to be using 2 spaces (example) and some of the .wat files also use 2 spaces (example). However, sometimes there is an inconsistent mix of 2 and 4 spaces (example).

I think it would be fine to leave indent_size unset if the choice is controversial.

[sunfishcode]

I think either way is fine. Our plan is to rewrite the remaining handful of .cpp files into Rust anyway :-).

[sunfishcode]

One thing I'm unclear on about editorconfig files; we already have a .rustfmt file, and we use all default settings; shouldn't we expect editors to either read the .rustfmt file, or at least default to rustfmt's defaults?

[bjorn3]

.editorconfig is meant to be supported by all editors, not just those that support rust. It also applies to all text files, not only rust files.

[silvanshade]

@sunfishcode the .rustfmt is good but only applies to Rust files. Other things like .c or .wat or random text files won't get the benefit from that configuration.

The main thing I find useful about having the .editorconfig is that line endings are configured project-wide. I often use windows for development and prefer not to force the editor to LF globally since I sometimes edit system files as well. It's not critical or anything, just nice to have.

[abrown]

I think this might be extra-helpful if it told IDEs to wrap lines to a certain length; I tend to forget to do that for non-Rust files.

[sunfishcode]

For LF line endings, should we add a .gitattributes file containing * text=auto eol=lf? That way git would handle it automatically for all text files, not just files created by editorconfig-aware editors.

[silvanshade]

Yeah the .gitattributes approach would also work for that. For reference, here is the rust-lang/rust/.gitattributes which does that.

[sunfishcode]

I submitted #1370 to add a .gitattributes file, following your suggestion.

If anyone has a clear need for a .editorconfig file beyond that, we can add it, but otherwise my sense is to wait until we have one. #1365 has now removed most of the remaining C++ code from the repo, which further simplifies things.

[silvanshade]

Sounds good. I'll close this in favor of the other PR.