git-dummy

Generate dummy Git repositories and populate them with the desired number of commits, branches, merges, and structure.

Example: $ git-dummy --commits=10 --branches=4 --merge=1

This will initialize a new Git repo in the current directory with 4 branches, each containing 10 commits, 1 of which is merged back into main.

Note: All generated dummy repos have at minimum 1 branch called main. For dummies with multiple branches, branches are named branch1, branch2, ..., branchN. Each branch currently branches off of main at --diverge-at if supplied, or else a randomly chosen commit. The length of each branch is capped at the number of commits specified by --commits. Use --merge=x,y,...,n to select which branches get merged back into main.

Use cases

Programatically generate Git repos for functional testing of Git tools
Decide how many commits and branches are generated
Select which branches get merged back into main
Mimic scenarios in real Git repos to practice on without touching real data
Generate Git demo repos to teach or learn from

Features

Run a one-liner git-dummy command in the terminal to generate a dummy Git repo based on your parameters
Customize the repo name, path, number of commits, branches, merges, and structure

Quickstart

Install git-dummy:

$ pip install git-dummy

Browse to the directory you want to create your dummy Git repo in:

$ cd path/to/dummy/parent

Run the program:

$ git-dummy [options]

A new Git repo called dummy will be initialized and populated based on the supplied parameters.
See global help for list of global options/flags and subcommands:

$ git-dummy -h

Requirements

Python 3.7 or greater
Pip (Package manager for Python)

Command options and flags

Available options and flags include:

--name: The name of the dummy Git repo, defaults to "dummy".
--commits: The number of commits to populate in the dummy Git repo, defaults to 5.
--branches: The number of branches to generate in the dummy Git repo, defaults to 1.
--diverge-at: The commit number at which branches diverge from main.
--merge: A comma separated list of branch postfix ids to merge back into main.
--git-dir: The path at which to store the dummy Git repo, defaults to current directory.
--no-subdir: Initialize the dummy Git repo in the current directory instead of in a subdirectory.
--constant_sha: Use constant values for commit author, email, and commit date parameters to yield consistent sha1 values across git-dummy runs.
--allow-nested: Allow dummy repo creation within an existing Git repo, as long as it's not at the level of an existing .git/ folder.

Command examples

Generate a dummy Git repo called "cheese" on your Desktop, with 2 branches and 10 commits on each branch:

$ git-dummy --name=cheese --branches=2 --commits=10 --git-dir=~/Desktop

Generate a dummy repo with 4 branches main, branch1, branch2, and branch3. Branches diverge from main after the 2nd commit:

$ git-dummy --branches=4 --diverge-at=2

Generate a dummy repo with 4 branches, so that branch1 and branch3 are merged back into main:

$ git-dummy --branches=4 --merge=1,3

For convenience, environment variables can be set for any command-line option available in git-dummy. All environment variables start with git_dummy_ followed by the name of the option.

For example, the --git-dir option can be set as an environment variable like:

$ export git_dummy_git_dir=~/Desktop

Similarly, the --name option can be set like:

$ export git_dummy_name=cheese

In general:

$ export git_dummy_option_name=option_value

Explicitly specifying options at the command-line takes precedence over the corresponding environment variable values.

Learn More

Learn more about this tool on the git-dummy project page.

Authors

Jacob Stopak - on behalf of Initial Commit