Forest

Forest is a tool intended to replace git log --graph with something prettier. I made this repo because it was maddening to me that there are all these forks and copies of (git-)forest(a) and no clarity regarding their differences.

In order to integrate git-forest into vim-flog, I wanted to first be sure that I have all features and bugfixes merged into one repo.

Forks / Copies

Forest was originally created in 2008 Jan Engelhardt. His repository is still present here, but I have pushed this github mirror so that I can share http links to commits.

There are four forks that I am aware of, and vim-flog-forest is an attempt to reconcile all their improvements, while staying compatible with vim-flog.

The original 2008 HXTools, with a github mirror here.
John Wiegley's 2013 copy in git-scripts
Takaaki Kasai's 2017 copy git-foresta
Roger Bongers' 2021 fork of git-scripts

Key differences

Fix hxtools git-forest

The original hxtools git-forest needs this modification to even run on modern perl versions:

@@ -12,7 +12,7 @@
 use Getopt::Long;
 use Git;
 use strict;
-use encoding "utf8";
+use utf8;
 my $Repo          = Git->repository($ENV{"GIT_DIR"} || ".");
 my $Pretty_fmt    = "format:%s";
 my $Reverse_order = 0;

Coloured branches with git-foresta

Git-foresta chooses a colour for each branch, and sticks with it, making it easier to see which commits belong to each.

But, git-foresta doesn't support vim-flog

As mentioned here, git-foresta does not accept a custom format, and hence vim-flog won't work.

Benchmark

Using hyperfine, I found the original hxtools git-forest is 10% faster than the git-scripts' version, and 15% faster than git-foresta.

Benchmark #1: ./git-foresta
  Time (mean ± σ):      73.2 ms ±   1.0 ms    [User: 60.0 ms, System: 16.1 ms]
  Range (min … max):    71.6 ms …  75.2 ms    40 runs

Benchmark #2: ../hxtools/sdevel/git-forest
  Time (mean ± σ):      63.4 ms ±   1.0 ms    [User: 52.5 ms, System: 13.1 ms]
  Range (min … max):    61.6 ms …  65.6 ms    46 runs

Benchmark #3: ../git-scripts/git-forest
  Time (mean ± σ):      70.0 ms ±   0.8 ms    [User: 61.2 ms, System: 10.9 ms]
  Range (min … max):    68.2 ms …  71.6 ms    42 runs

Summary
  '../hxtools/sdevel/git-forest' ran
    1.10 ± 0.02 times faster than '../git-scripts/git-forest'
    1.15 ± 0.02 times faster than './git-foresta'

Grafting repo's

In order to be able to reconcile these copies, I set out to find versions of each that correspond to each other, so that the version in one repo can be rebased onto the other. I found:

John Wiegley's first commit (re-)adding git-forest, 1d2a0e36cc, is identical to Jan Engelhardt's 2ef51708fb0 (then named bin/git-forest, later renamed sdevel/git-forest). There seem to be fixes in both repositories that did not make it into the other.
Unfortunately Takaaki Kasai has made so many changes in the very first commit, that it is difficult to pinpoint where he got the script from. But it seems from line 224 of his first commit that he has included the latest of Jan Engelhardt's fixes, b9b2bf1543. Also, I can't find any place to even apply John Wiegley's changes, as all those lines seem to be missing in git-foresta from the beginning.

First, each repository is converted to only contain git-forest. Then, they can be merged.

extract_hxtools

For hxtools, we use git filter-branch --tree-filter '~/code/forest_forks/extract_hxtools' --prune-empty -f HEAD.

The following extract_hxtools script deletes everything but git-forest, and ensures it is called git-forest and in the root of the repo:

#!/usr/bin/env bash

find . -type d | grep -v '^\./\.git\|^\.$\|^\./sdevel$\|^\./bin$' | xargs rm -rf
find . -type f | grep -v '^\./\.git\|git-forest$' | xargs rm -f
rm -f .gitignore
rm -f NEWS.rst

if [[ -f "bin/git-forest" ]]; then
  mv bin/git-forest .
fi
if [[ -f "sdevel/git-forest" ]]; then
  mv sdevel/git-forest .
fi

rm -rf sdevel
rm -rf bin

The resulting filtered hxtools history of git-forest is available as hxtools_git_forest.

extract_git-scripts

Similarly for git-scripts, there is git filter-branch --tree-filter '~/code/forest_forks/extract_git-scripts' --prune-empty -f HEAD.

#!/usr/bin/env bash

find . -type d | grep -v '^\./\.git\|^\.$' | xargs rm -rf
find . -type f | grep -v '^\./\.git\|git-forest$' | xargs rm -f
find . -type l | xargs rm
rm -f .gitignore

Because the script was removed and then re-added, this leaves some noise commits near the root of the repo, which are removed by magic. Finally, the unnecessary merges are removed with a rebase without --preserve-merges onto the aforementioned corresponding commit in hxtools.

The resulting filtered git-scripts history of git-forest is available as git_scripts_forest.

extract_foresta

And for git-foresta, git filter-branch --tree-filter '~/code/forest_forks/extract_foresta' --prune-empty -f HEAD

#!/usr/bin/env bash

find . -type d | grep -v '^\./\.git\|^\.$\|^\./script$' | xargs rm -rf
find . -type f | grep -v '^\./\.git\|git-foresta$' | xargs rm -f
rm -f .gitignore

if [[ -f "script/git-foresta" ]]; then
  mv script/git-foresta git-forest
fi
if [[ -f "git-foresta" ]]; then
  mv git-foresta git-forest
fi

rm -rf script/

The resulting filtered git-foresta history of git-forest is available as git_foresta.

rbong / git-forest