How-To's

Using an autoformatter will make your process easier but it can also introduce a few pain points. Here are how to solve the most commonly encountered pain points.

Using OCamlFormat without breaking git blame

• Create .git-blame-ignore-revs in your project
• Add revision(s) where the code was re-formatted

# Apply new formatting with OCamlFormat
2ceaf76b9f84cb632327c1479d0f30acfa3eeba2

• Run git config --local blame.ignoreRevsFile .git-blame-ignore-revs
• All future use of git blame will now provide blame information omitting the reformatting commits: lines that were changed or added by an ignored commit will be blamed on the previous commit that changed that line or nearby lines.

Resolve merge conflicts using Merge-fmt and OCamlFormat

Merge-fmt is a small wrapper on top of git commands to help resolve conflicts caused by code formatters.

There are three ways to use merge-fmt.

Standalone

Just call merge-fmt while there are unresolved conflicts. merge-fmt will try to resolve conflicts automatically.

As a Git mergetool

merge-fmt can act as a git mergetool. First configure the current git repository with

merge-fmt setup-mergetool
git config --local mergetool.mergefmt.cmd 'merge-fmt mergetool --base=$BASE --current=$LOCAL --other=$REMOTE -o $MERGED'
git config --local mergetool.mergefmt.trustExitCode true

Then, use git mergetool to resolve conflicts with git mergetool -t mergefmt.

As a git merge driver

merge-fmt can act as a git merge driver. Configure the current git repository to use merge-fmt as the default merge driver.

$ merge-fmt setup-merge
git config --local merge.mergefmt.name 'merge-fmt driver'
git config --local merge.mergefmt.driver 'merge-fmt mergetool --base=%O --current=%A --other=%B -o %A --name=%P'
git config --local merge.tool 'mergefmt'
git config --local merge.default 'mergefmt'