Git Commit Guidelines

We have very precise rules over how our git commit messages can be formatted. This leads to more readable messages that are easy to follow when looking through the project history. But also, we use the git commit messages to generate the change log.

Commit Message Format

Each commit message consists of a header, a body and a footer. The header has a special format that includes a type, a scope and a subject:

<type>(<scope>): <subject>
<BLANK LINE>
<body>
<BLANK LINE>
<footer>

Any line of the commit message cannot be longer 100 characters! This allows the message to be easier to read on github as well as in various git tools.

Type

Must be one of the following:

feat: A new feature
fix: A bug fix
docs: Documentation only changes
style: Changes that do not affect the meaning of the code (white-space, formatting, missing semi-colons, etc)
refactor: A code change that neither fixes a bug or adds a feature
perf: A code change that improves performance
test: Adding missing tests
chore: Changes to the build process or auxiliary tools and libraries such as documentation generation

Scope

The scope should refer to a module in hyper that is being touched. Examples:

client
server
http1
http2
ffi
upgrade
examples

Subject

The subject contains succinct description of the change:

use the imperative, present tense: “change” not “changed” nor “changes”
don’t capitalize first letter
no dot (.) at the end

Body

Just as in the subject, use the imperative, present tense: “change” not “changed” nor “changes” The body should include the motivation for the change and contrast this with previous behavior.

The footer should contain any information about Breaking Changes and is also the place to reference GitHub issues that this commit Closes.