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Conventional Commits 1.0.0-beta.1

Summary

As an open-source maintainer, squash feature branches onto master and write a standardized commit message while doing so.

The commit message should be structured as follows:


<type>[optional scope]: <description>

[optional body]

[optional footer]


The commit contains the following structural elements, to communicate intent to the consumers of your library:

  1. fix: a commit of the type fix patches a bug in your codebase (this correlates with PATCH in semantic versioning).
  2. feat: a commit of the type feat introduces a new feature to the codebase (this correlates with MINOR in semantic versioning).
  3. BREAKING CHANGE: a commit that has the text BREAKING CHANGE: at the beginning of its optional body or footer section introduces a breaking API change (correlating with Major in semantic versioning). A breaking change can be part of commits of any type. e.g., a fix:, feat: & chore: types would all be valid, in addition to any other type.


A scope may be provided to a commit’s type, to provide additional contextual information and is contained within parenthesis, e.g., feat(parser): adds ability to parse arrays.

Commit types other than fix: and feat: are allowed, for example the Angular convention recommends docs:, style:, refactor:, perf:, test:, chore:, but these tags are not mandated by the conventional commits specification.

Introduction

In software development, it’s been my experience that bugs are most often introduced at the boundaries between applications. Unit testing works great for testing the interactions that an open-source maintainer knows about, but do a poor job of capturing all the interesting, often unexpected, ways that a community puts a library to use.

Anyone who has upgraded to a new patch version of a dependency, only to watch their application start throwing a steady stream of 500 errors, knows how important a readable commit history (and ideally a well maintained CHANGLOG) is to the ensuing forensic process.

The Conventional Commits specification proposes introducing a standardized lightweight convention on top of commit messages. This convention dovetails with SemVer, asking software developers to describe in commit messages, features, fixes, and breaking changes that they make.

By introducing this convention, we create a common language that makes it easier to debug issues across project boundaries.

Conventional Commits Specification

The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in RFC 2119.

  1. commits MUST be prefixed with a type, which consists of a verb, feat, fix, etc., followed by a colon and a space.
  2. the type feat MUST be used when a commit adds a new feature to your application or library.
  3. the type fix MUST be used when a commit represents a bug fix for your application.
  4. an optional scope MAY be provided after a type. A scope is a phrase describing a section of the codebase enclosed in parenthesis, e.g., fix(parser):
  5. A description MUST immediately follow the type/scope prefix. The description is a short description of the pull request, e.g., fix: array parsing issue when multiple spaces were contained in string.
  6. A longer commit body MAY be provided after the short description. The body MUST begin one blank line after the description.
  7. A footer MAY be provided one blank line after the body. The footer SHOULD contain additional meta-information about the pull-request (such as the issues it fixes, e.g., fixes #13, #5).
  8. Breaking changes MUST be indicated at the very beginning of the footer or body section of a commit. A breaking change MUST consist of the uppercase text BREAKING CHANGE, followed by a colon and a space.
  9. A description MUST be provided after the BREAKING CHANGE: , describing what has changed about the API, e.g., BREAKING CHANGE: environment variables now take precedence over config files.
  10. types other than feat and fix MAY be used in your commit messages.

Why Use Conventional Commits

FAQ

How should I deal with commit messages in the initial development phase?

We recommend that you proceed as if you’ve an already released product. Typically somebody, even if its your fellow software developers, is using your software. They’ll want to know what’s fixed, what breaks etc.

What do I do if the commit conforms to more than one of the commit types?

Go back and make multiple commits whenever possible. Part of the benefit of Conventional Commits is its ability to drive us to make more organized commits and PRs.

Doesn’t this discourage rapid development and fast iteration?

It discourages moving fast in a disorganized way. It helps you be able to move fast long term across multiple projects with varied contributors.

Might Conventional Commits lead developers to limit the type of commits they make because they’ll be thinking in the types provided?

Conventional Commits encourages us to make more of certain types of commits such as fixes. Other than that, the flexibility of Conventional Commits allows your team to come up with their own types and change those types over time.

How does this relate to SemVer?

fix type commits should be translated to PATCH releases. feat type commits should be translated to MINOR releases. Commits with BREAKING CHANGE in the commits, regardless of type, should be translated to MAJOR releases.

How should I version my extensions to the Conventional Commits Specification, e.g. @jameswomack/conventional-commit-spec?

We recommend using SemVer to release your own extensions to this specification (and encourage you to make these extensions!)

What do I do if I accidentally use the wrong commit type?

When you used a type that’s of the spec but not the correct type, e.g. fix instead of feat

Prior to merging or releasing the mistake, we recommend using git rebase -i to edit the commit history. After release, the cleanup will be different according to what tools and processes you use.

When you used a type not of the spec, e.g. feet instead of feat

In a worst case scenario, it’s not the end of the world if a commit lands that does not meet the conventional commit specification. It simply means that commit will be missed by tools that are based on the spec.

Do all my contributors need to use the conventional commit specification?

No! If you use a squash based workflow on Git lead maintainers can cleanup the commit messages as they’re merged—adding no workload to casual committers. A common workflow for this is to have your git system automatically squash commits from a pull request and present a form for the lead maintainer to enter the proper git commit message for the merge.

About

The Conventional Commit specification is inspired by, and based heavily on, the Angular Commit Guidelines.

The first draft of this specification has been written in collaboration with some of the folks contributing to:

Projects Using Conventional Commits

Conventional Commits

want your project on this list? send a pull request.

License

Creative Commons - CC BY 3.0