git when-merged helps you figure out when and why a commit was merged into a branch.
If you use standard Git workflows, then you create a feature branch for each feature that you are working on. When the feature is complete, you merge it into your master branch. You might even have sub-feature branches that are merged into a feature branch before the latter is merged.
In such a workflow, the first-parent history of master consists mainly of merges of feature branches into the mainline. git when-merged can be used to ask, "When (and why) was commit C merged into the current branch?" The simplest way to use it is
$ git when-merged 87c248f
refs/heads/master 50f577451448a407ee8e78ed62aa09d209c91652This command looks along the first-parent history of the current branch to find the merge commit that first brought commit 87c248f into the branch's history. The guilty merge commit in this case is 50f5774. Add the -l option to see the log for that merge, which will hopefully explain what feature was being merged and by whom:
$ git when-merged -l 87c248f
refs/heads/master 50f577451448a407ee8e78ed62aa09d209c91652
commit 50f577451448a407ee8e78ed62aa09d209c91652 (github/master, master)
Merge: f79a45d 87c248f
Author: Michael Haggerty <mhagger@alum.mit.edu>
Date: Mon Jul 11 07:55:19 2016 +0200
Merge pull request #9 from mhagger/recursive-option
Add a `--recursive`/`-r` optionThere are many more options; see below.
Note: If you are using 2.6 <= Python <= 3.6, you MUST use Option 3 or 4.
pipx is a tool to help you install and run end-user applications written in Python.
-
python3 -m pip install --user pipx
- Tip: Homebrew as well as newer versions of some Linux distributions (e.g. Debian 10, Ubuntu 19.04, etc.) offer native packages for
pipx.
python3 -m pipx ensurepath
- Note: You may need to restart your terminal for the
$PATHupdates to take effect.
- Tip: Homebrew as well as newer versions of some Linux distributions (e.g. Debian 10, Ubuntu 19.04, etc.) offer native packages for
-
Use
pipxto installgit-when-mergedfrom PyPI:pipx install git-when-merged
-
Test the installation:
git-when-merged --help
-
Use
pipxto uninstall at any time:pipx uninstall git-when-merged
See Python's Installing stand alone command line tools guide for more information.
Python "Virtual Environments" allow Python packages to be installed in an isolated location for a particular application, rather than being installed globally.
-
Use the built-in
venvmodule to create a virtual environment:python3 -m venv ./venv-gwm
-
Use
pipto installgit-when-mergedfrom PyPI into the virtual environment:venv-gwm/bin/pip install git-when-merged
-
Test the installation:
venv-gwm/bin/git-when-merged --help
-
Tip: Some users find it more convenient to "activate" the virtual environment (which prepends the virtual environment's
bin/to$PATH):source venv-gwm/bin/activate git-when-merged --help deactivate
-
-
Remove the virtual environment to uninstall at any time:
rm --recursive venv-gwm/
See Python's Installing Packages tutorial for more information.
-
Clone the repo somewhere on your system.
-
Ensure that
<somewhere>/bin/git-when-mergedis executable. -
Put the contents of
<somewhere>/binon your$PATH.
That's it!
git when-merged [OPTIONS] COMMIT [BRANCH...]
Find the merge commit that brought COMMIT into the specified BRANCH(es). Specifically, look for the oldest commit on the first-parent history of each BRANCH that contains the COMMIT as an ancestor.
positional arguments:
commit The commit whose destiny you would like to determine.
branch The destination branch(es) into which <commit> might
have been merged. (Actually, BRANCH can be an
arbitrary commit, specified in any way that is
understood by git-rev-parse(1).) If neither <branch>
nor --pattern/-p nor --default/-s is specified, then
HEAD is used.
optional arguments:
-h, --help show this help message and exit
--pattern PATTERN, -p PATTERN
Show when COMMIT was merged to the references matching
the specified regexp. If the regexp has parentheses
for grouping, then display in the output the part of
the reference name matching the first group.
--name NAME, -n NAME Show when COMMIT was merged to the references matching
the configured pattern(s) with the given name (see
whenmerged.<name>.pattern below under CONFIGURATION).
--default, -s Shorthand for "--name=default".
--recursive, -r Follow merges back recursively.
--show-commit, -c Display only the SHA-1 of the merge commit. Exit with
a nonzero exit code if the commit was not merged via a
merge commit.
--show-branch, -b Display the range of commits that were merged at the
same time as the specified commit. Exit with a nonzero
exit code if the commit was not merged via a merge
commit. This option also affects the behavior of --log
and --visualize.
--abbrev N Abbreviate commit SHA-1s to the specified number of
characters (or more if needed to avoid ambiguity). See
also whenmerged.abbrev below under CONFIGURATION.
--no-abbrev Do not abbreviate commit SHA-1s.
--describe Describe the merge commit in terms of the most recent
tag reachable from the commit (see git-describe(1))
--describe-contains Describe the merge commit in terms of a nearby tag
that contains it (see git-describe(1))
--log, -l Show the log for the merge commit. When used with
"--show-branch/-b", show the log for all of the
commits that were merged at the same time as the
specified commit.
--diff, -d Show the diff for the merge commit.
--visualize, -v Visualize the merge commit using gitk. When used with
"--show-branch/-b", only show the branch(es) that were
merged at the same time as the specified commit.
Examples:
git when-merged 0a1b # Find the merge commit that brought
# commit 0a1b into the current branch
git when-merged 0a1b v1.10 v1.11 # Find merge into given tags/branches
git when-merged 0a1b -p feature-[0-9]+ # Specify tags/branches by regex
git when-merged 0a1b -n releases # Use whenmerged.releases.pattern
git when-merged 0a1b -s # Use whenmerged.default.pattern
git when-merged -r 0a1b # If the commit was merged indirectly,
# show each intermediate merge.
git when-merged -l 0a1b # Show the log for the merge commit
git when-merged -lb 0a1b # Show log for the whole merged branch
git when-merged -v 0a1b # Visualize the merge commit in gitk
git when-merged -vb 0a1b # Visualize the whole merged branch
git when-merged -d 0a1b # Show the diff for the merge commit
git when-merged -c 0a1b # Print only the merge's SHA-1
Configuration:
whenmerged.<name>.pattern
Regular expressions that match reference names for the pattern
called <name>. A regexp is sought in the full reference name,
in the form "refs/heads/master". This option can be multivalued, in
which case references matching any of the patterns are considered.
Typically the pattern will be chosen to match master and/or significant
release branches or tags, or perhaps their remote-tracking equivalents.
For example,
git config whenmerged.default.pattern '^refs/heads/master$'
git config --add whenmerged.default.pattern '^refs/heads/maint$'
or
git config whenmerged.releases.pattern '^refs/tags/release-'
whenmerged.abbrev
If this value is set to a positive integer, then Git SHA-1s are
abbreviated to this number of characters (or longer if needed to
avoid ambiguity). This value can be overridden using --abbrev=N
or --no-abbrev.
git when-merged is originally based on the suggestion here.