pre-git

Important git hooks implemented using Nodejs for your project.

Why?

You can easily run the pre-commit and pre-push Git hooks to avoid breaking the local master branch or the remote master.

Installation

It's advised to install this module as devDependency in your package.json file so it doesn't get installed on production servers. Run:

npm install pre-git --save-dev

Configuration

Specify commands to run on commit and on push in your package.json under config > pre-git object.

"scripts": {
  "test": "node-qunit *.js"
},
"config": {
  "pre-git": {
    "enabled": true,
    "msg-pattern": "^(US|DE)\\d+ - .+",
    "commit-msg": "simple",
    "pre-commit": [
      "grunt jshint"
    ],
    "post-commit": "git status",
    "pre-push": [
      "rm -rf node_modules",
      "npm install",
      "grunt build",
      "grunt test"
    ],
    "post-checkout": "npm install",
    "post-merge": "npm install"
  }
}

If there are older settings like pre-commit, etc, you will have to move them to the config > pre-git object manually.

Related project: post-merge-make runs make post-merge after pull or merge.

Subprojects

If you have large repo, it is possible that there might be nested files with different package.json files. In this case, the search will proceed up from the current working directory until it finds package.json with valis config.pre-git object inside.

Windows

Thanks to ybiquitous for adding support for Windows.

• Git Bash (Git for Windows): work fine!
• Command prompt: work if sh.exe in PATH (e.g. set PATH=C:\Program Files\Git\bin;%PATH%)

Untracked files

Before the commit, we check if there are any untracked files. A commit does not continue if there are any. Please git ignore or delete unnecessary files before running the git commit command to ensure clean tests. In every case where I forgot to add files to the repo, this was by accident and caused breaking tests.

This can be disabled by setting the allow-untracked-files option to true

{
"config": {
  "pre-git": {
     "allow-untracked-files": true
  }
}

Details

You can disable all pre-git hooks by setting the configuration option to false

{
"config": {
  "pre-git": {
     "enabled": false
  }
}

If the 'config.pre-git' object has the option 'enabled' missing, it is assumed to be "true" and the hooks are executed.

You can always skip pre-commit hook (but not pre-push hook!) by using -n option

git commit -m "done, don't check me" -n

You can skip the pre-push hook using --no-verify option

To run just the hook (for example to test what it does), execute

.git/hooks/pre-commit
.git/hooks/pre-push

Since there might be no changes to push, you can force the pre-commit hook to execute using -f or --force argument

.git/hooks/pre-commit -f

Validating commit message

By default, this package will install both the message validator and the message format helper. You can disable the validation by removing the below command.

"config": {
  "pre-git": {
    "commit-msg": "conventional"
  }
}

When you run git commit -m "message ..." the hook will enforce the default style type(scope): message .... To better form the message, there is a CLI wizard installed based on commitizen project, very well shown in the tutorial video. The commit wizard is available under "node_modules/.bin/commit-wizard" link and can be started from command line

node --harmony node_modules/.bin/commit-wizard

or via a script

"scripts": {
  "commit": "commit-wizard"
}

Then run

npm run commit

The wizard will look something like this

? Select the type of change that you're committing:
  feat:     A new feature
❯ fix:      A bug fix
  chore:    Changes to the build process or auxiliary tools
            and libraries such as documentation generation

There are 2 plugins included with pre-git:

• "conventional" follows AngularJS log convention, see conventional-commit-message
• "simple" only allows "feat", "fix" and "chore" commit types, see simple-commit-message

I recommend sticking with "simple" unless you need more release types.

Development

In order to locally test this package, from another git repo execute the install script using -f or --force argument. For example

$ node ../pre-git/src/install.js -f
pre-git 0.7.2 in /Users/kensho/git/test-git-hooks
/Users/kensho/git/test-git-hooks
read target package from /Users/kensho/git/test-git-hooks/package.json
added empty command list for hook commit-msg
added empty command list for hook pre-commit
added empty command list for hook pre-push
added empty command list for hook post-commit
added empty command list for hook post-merge
saving updated files /Users/kensho/git/test-git-hooks/package.json

"config": {
  "pre-git": {
    "msg-pattern": "whatever-regex-without-delimiters"
  }
}

When using msg-pattern, the pre-git will match the commit message against the given pattern, if the test fails, then it will stop the execution and will exit the commit, this feature is optional and can be used along with any of the commit wizards, however those can be omitted using only the pattern, this is a useful manner of checking a custom message, as some commit may require custom codes as user story prefixes and so on.

It is also possible to customize your own msg-pattern-error along with msg-pattern to be more descriptive as to why the pattern fails.

"config": {
  "pre-git": {
    "msg-pattern": "whatever-regex-without-delimiters",
    "msg-pattern-error": "whatever error message that will be thrown when the pattern fails"
  }
}

I am using a small project test-pre-git as a test playground for these hooks.

End to end testing

To create a sample project and test the hooks, just run the included script npm run e2e which should finish with status zero.

To see how pre-git stops a commit when a hook fails, run npm run test-no-commit-on-test-fail command, which should exit with status 1.

You can verify the git hooks are not running when the pre-git is disabled via a config option by running npm run e2e-pre-git-disabled which allows the commit to go through.

To see how allow-untracked-files option lets the commit go through, run npm run test-allow-untracked-files

Debugging

If a hook does not behave as expected, you can see verbose log messages by setting the environment variable DEBUG=pre-git when running a git command. For example, to see the messages when committing

DEBUG=pre-git git commit -m "a message"
running pre-commit script
pre-git pre-commit +0ms arguments [ 'node',
  '/instant-vdom-todo/node_modules/.bin/pre-commit' ]
pre-commit No changes detected, bailing out.
pre-git found package in folder +0ms /instant-vdom-todo
pre-git commit message wizard name from +5ms
...

This should provide plenty of information to debug the hooks

Desktop Git clients

The Git hooks should work in desktop clients, like GitHub Desktop app. If something does not work, it is usually because the desktop App cannot find node. See what Git Tower application suggests you do in that case.

Local development

To execute commit message validation, run npm run demo-commit-message and vary the test message to see how the hook validates it.

Recent contributors

• ybiquitous
• Marko Schulz

Small print

Author: Gleb Bahmutov © 2014

• @bahmutov
• glebbahmutov.com
• blog

License: MIT - do anything with the code, but don't blame me if it does not work.

Spread the word: tweet, star on github, etc.

Support: if you find any problems with this module, email / tweet / open issue on Github