branch-commit-msg

Overview

branch-commit-msg is a git commit-msg hook that extracts a configurable regex pattern from the current branch and reformats the final commit message to the configured format.

Installation

With no dependency:

$ npx branch-commit-msg install

With husky:

$ npm install -D branch-commit-msg
$ npx husky add .husky/commit-msg 'npx branch-commit-msg-hook "$1"'

Uninstall

With no dependency:

$ rm .git/hooks/commit-msg

With husky:

Remove npx branch-commit-msg-hook "$1" from .husky/commit-msg and run:

$ npm uninstall branch-commit-msg

Usage

After installation, create a .commitmsgrc.json file at the root of your project and configure how you would like to reformat your final commit message based on elements of the active branch name:

// .commitmsgrc.json

{
  /*
    Regex group pattern to extract from branch name.
      - ex: "(sc)-?[0-9]+"
  */
  "extractPattern": string,

  /*
    Whether the extractPattern is case-sensitive.
      - ex: true
  */
  "extractPatternMatchCase": boolean,

  /*
    Final output format for the commit message.

    Formatting Placeholders:
      %b0: access the entire matched pattern from the branch name
      %b1: access the first matched group pattern from the branch name
      %bn: access the 'n'th matched group pattern from the branch name
        - ex: "%b6" accesses the 6th matched group pattern
      %m: the original commit message

    Pipes:
      lower: applies lower casing to the formatting placeholder
        - ex: "$b2 | lower"
      upper: applies upper casing to the formatting placeholder
        - ex: "%m | upper"
  */
  "commitMsgFormat": string
}

After your .commitmsgrc.json is configured, start making commits!

Configuration Examples

Preface commit message with a Shortcut ticket number:

{
  "extractPattern": "sc-[0-9]+",
  "extractPatternMatchCase": false,
  "commitMsgFormat": "%b0 - %m"
}

# Current branch: SC-123456/my-new-feature
$ git commit -m "added a thing"
$ git log -1 --pretty=%B
# Output: SC-123456 - added a thing

Suffix and format a commit message with a JIRA ticket:

{
  "extractPattern": "SOMEPRJ-[0-9]+",
  "extractPatternMatchCase": false,
  "commitMsgFormat": "%m (%b0 | upper)"
}

# Current branch: feature/someprj-123456
$ git commit -m "added a thing"
$ git log -1 --pretty=%B
# Output: added a thing (SOMEPRJ-123456)

Go crazy with group matching:

{
  "extractPattern": "(some).*(complex[0-9-]+).*(branch)",
  "extractPatternMatchCase": false,
  "commitMsgFormat": "%m | upper to %b1 | upper %b2 %b3 | lower"
}

# Current branch: some/CoMpLEX-123-5/BRANCH
$ git commit -m "added a thing"
$ git log -1 --pretty=%B
# Output: ADDED A THING to SOME CoMpLEX-123-5 branch

Development

Prerequisites

• Docker installation (for integration and end-to-end (e2e) testing)
• Node.js (>=14.0.0) runtime
• Yarn installation

Install Dependencies

$ yarn install

Test

$ yarn test[:unit|:integration|:e2e|:smoke]

Build

$ yarn build