Add EditorConfig file

[hyperupcall]

While working on #1021, I noticed that some files like git-delta don't end in a newline. As a result, that last "line" (git diff --name-only --diff-filter=$filter $branch) is not considered part of the text file, according to POSIX.

To fix this, I propose adding an EditorConfig file. When editors read this (some require a plugin like VSCode) file, it adjusts the formatting based on the rules. One thing to note is that rules that specify whitespace are only take affect to each inserted text. For example, with indent_style = space, when editing a file that predominately uses tabs, only the spaces will be inserted on each <tab> - other characters are not modified.

It seems both 2 and 4-space shell scripts are used in this repository, so I decided to omit that constraint from the .editorconfig file.

[spacewander]

Can we add a job to check it in the CI?

[hyperupcall]

Is there anything in particular you wish to check? For consistent formatting for all of the files then maybe shfmt can be added in a different PR with CI. But EditorConfig isn't really the tool for that and there doesn't exist any first-party tools for checking EditorConfig rules.

[spacewander]

Some search brings me to https://github.com/editorconfig-checker/editorconfig-checker.

[hyperupcall]

editorconfig-checker is a third-party tool so I was hesitant to add it. Since there isn't an autofix mode, there is no automatic way of it conforming to the .editorconfig without something like shfmt to do the heavy lifting for us.

[hyperupcall]

What are your thoughts on shfmt?

[spacewander]

I don't like a formatter, which forces other people to use a style that is not used in their daily life.

[hyperupcall]

Fair enough - I don't use shfmt either.

How about adding editorconfig-checker to CI to only run on changes files?

[spacewander]

Fair enough - I don't use shfmt either.

How about adding editorconfig-checker to CI to only run on changes files?

LGTM

[hyperupcall]

Epic 👍

I also changed Ubuntu version since 18.04 is being currently phased out with brownouts

[spacewander]

I see some warnings in https://github.com/tj/git-extras/actions/runs/3979079395/jobs/6821262963

Warning: The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

Can it be avoided?

[hyperupcall]

I switched to masesgroup/retrieve-changed-files@v2, which fixed this issue

[spacewander]

Let's change it back once this PR is approved.

[hyperupcall]

The lint checks work with the new changes.

I also changed the pull_request.branches back, but I'm not sure how contributors are supposed to know if their files are formatted correctly

[spacewander]

The lint checks work with the new changes.

I also changed the pull_request.branches back, but I'm not sure how contributors are supposed to know if their files are formatted correctly

They can check this locally? It would be good to add an editorconfig plugin in the editor. Anyway, they can also figure it out by reading the output of the CI.

[hyperupcall]

Oh oops 🤦 - for some reason I thought that CI wouldn't run if pull_request.branches wasn't *. But I now see that the other PRs show CI.

Is this ready to go?

[spacewander]

Oh oops 🤦 - for some reason I thought that CI wouldn't run if pull_request.branches wasn't *. But I now see that the other PRs show CI.

Is this ready to go?

Merged. Thanks!