2 releases

0.1.4 Feb 16, 2022
0.1.3 Oct 2, 2021

#2428 in Command line utilities

MIT/Apache

80KB
2K SLoC

Oaf, a nicer Git

Oaf is a Git client that brings a more user-friendly CLI to Git.

It's based on the following ideas:

  1. Merge is used to apply the changes introduced in another branch to the current branch.
  2. The commits done in a branch are different from the commits merged into a branch.
  3. Merges are a good thing that should be encouraged. They prevent conflicts from happening later, by establishing a clear precedence between two sets of changes.
  4. Merges can introduce logical conflicts, so the user should have the opportunity to test a merge before committing it.
  5. Push and Pull are operations to synchronize two copies of the same branch.
  6. -- is used to separate options from inputs that might look like options, not to separate file inputs from other kinds of inputs.
  7. Working on several branches at once should be as easy as possible.
  8. Users should have the opportunity to see what changes would be introduced by merging their current work into its eventual target.
  9. It is usually a bad idea to commit a version of the code that has never existed on disk.
  10. The Git index (staging area/cache) is an implementation detail that is not useful to most users.
  11. History is valuable, and should usually be preserved. It allows later readers to understand the precise context in which a change was introduced.

Differences from Git

New commands

  • merge-diff command to show what would happen if you committed and and merged your changes into a branch.
  • cat command to retrieve old versions of files.
  • fake-merge to pretend to merge a branch, while actually making no changes to your local contents.
  • squash-commit convert the current set of commits into a single commit.
  • ignore ignores the specified files by updating .gitignore

New commands as Git external commands

All new commands can also be used as Git external commands, as long as the oaf binary can be accessed via that name prefixed with 'git-'. e.g. by running ln -s ~/.local/bin/oaf ~/.local/bin/git-merge-diff you can then run git merge-diff. (This assumes that ~/.local/bin is in your path, and you have oaf installed there.)

Commands with changed behaviour

  • merge defaults to merge --no-ff --no-commit. --no-commit (1.). --no-ff is because merge and pull are distinct.
  • pull uses --ff-only (5.).
  • log shows only commits from the current branch (and its ancestors) by default. (2.)
  • For a branch that has never been pushed before, push will automatically push to origin with the current branch's name.
  • switch allows you to pick up where you left off, without committing or explicitly stashing your pending changes. (7.)
  • commit defaults to -a (10.). To commit only some changes, consider using oaf stash [-p] to temporarily remove unwanted changes. This gives you an opportunity to test that version before committing it (8.).
  • diff defaults to HEAD for its source (10.). It provides source and target as options (6.). It defaults to patience diff to prefer contiguous matches over longer, broken-up matches.
  • restore defaults to HEAD for its source (10.).
  • status uses a short format. When determining whether a file is modified, it (effectively) compares the working tree to HEAD (10.).

Note: if you just want the new commands, not the changed behaviour, see "New commands as Git external commands" above.

Obsolete commands

  • checkout is superseded by switch or restore.

Unchanged commands

All commands not listed by oaf help will automatically fall through to git. So oaf write-tree -h is the same as git write-tree -h.

Extensions

Because oaf falls through to git, oaf will also fall through to external git commands. So git-lfs can also be invoked as oaf lfs. Currently, Oaf does not have native support for extension.

Interoperability

File-format compatibility

Oaf is a front-end for Git, so all of its operations on repositories are performed by invoking Git commands. Everything it does could be accomplished by a series of Git commands, meaning everything is completely compatible with Git.

Interchange with other users

The use of merge improves mechanical interoperability, but may cause friction with some Git users and tools. Most developers would agree that the changes introduced on a branch are special in the context of that branch, but some do not wish to use the first-parent mechanism to distinguish between branch commits and merged-in commits. Because of this, they consider all merges to hamper readability.

Since maintaining first-parent ancestry is not a priority, they may mess it up through fast-forward "merges", especially foxtrot "merges".

Note that using rebase in place of merge can also hamper interoperability, so this a catch-22, but one that Git users have long accepted.

Installation

Oaf is in its early days, so binaries are provided for only x86-64.

It is written in the Rust language, so you'll need a copy of the Rust toolchain to install from source. The easiest way to do that is: cargo install --locked oaf. This will install the latest published version.

Git must be installed for Oaf to function. Oaf is typically tested with Git 2.25.x

History

Oaf draws some inspiration from my previous work on

  • Bazaar VCS
  • the bzrtools plugins
  • Fai, the Friendly Arch Interface
  • aba, an Arch I wrote in shell to add support for Git-style external commands.

While the Git repository format won out over Bazaar, many concepts from the Bazaar user model can be applied to Git. Oaf is my attempt to begin to do that. There is also Breezy, which is a fork of Bazaar with Git support built-in.

Dependencies

~4MB
~68K SLoC