AI21Labs/pre-commit-hook-yamlfmt

AI21Labs/pre-commit-hook-yamlfmt

Description: YAML formatter for http://pre-commit.com

License: MIT

Stars: 0

Forks: 0

Open issues: 1

Created: 2026-08-11T06:13:40Z

Pushed: 2026-08-11T06:26:25Z

Default branch: master

Fork: yes

Parent repository: jumanjihouse/pre-commit-hook-yamlfmt

Archived: no

README:

YAML formatter for pre-commit git hooks

YAML formatter for pre-commit.

This hook formats the indentation of YAML files and optionally aligns top-level colons.

It uses ruamel.yaml to do the heavy lifting and preserve comments within YAML files.

• [How-to](#how-to)
• [Configure pre-commit](#configure-pre-commit)
• [Use defaults](#use-defaults)
• [Combine with yamllint](#combine-with-yamllint)
• [Override defaults](#override-defaults)
• [Invoke pre-commit](#invoke-pre-commit)
• [On every commit](#on-every-commit)
• [On demand](#on-demand)
• [Contributing](#contributing)
• [Testing](#testing)
• [License](#license)

How-to

Configure pre-commit

Use defaults

Add to .pre-commit-config.yaml in your git repo:

• repo: https://github.com/jumanjihouse/pre-commit-hook-yamlfmt

rev: 0.2.1 # or other specific tag hooks:

• id: yamlfmt

:bulb: If a pre-commit hook changes a file, the hook fails with a warning that files were changed.

The default settings are:

• mapping: 4 spaces
• sequence: 6 spaces
• offset: 4 spaces
• colons: do _not_ align top-level colons
• width: None (use ruamel default)

Given this input:

foo: bar:

• baz1
• baz2

The default settings result in this output:

--- foo: bar:

• baz1
• baz2

Combine with yamllint

yamlfmt only works with valid YAML files, so I recommend to use yamllint and yamlfmt together.

• repo: https://github.com/adrienverge/yamllint.git

rev: v1.21.0 # or higher tag hooks:

• id: yamllint

args: [--format, parsable, --strict]

• repo: https://github.com/jumanjihouse/pre-commit-hook-yamlfmt

rev: 0.2.1 # or other specific tag hooks:

• id: yamlfmt

Override defaults

Add to .pre-commit-config.yaml in your git repo:

• repo: https://github.com/jumanjihouse/pre-commit-hook-yamlfmt

rev: 0.2.1 # or other specific tag hooks:

• id: yamlfmt

args: [--mapping, '2', --sequence, '2', --offset, '0', --colons, --width, '150']

Invoke pre-commit

On every commit

If you want to invoke the checks as a git pre-commit hook, run:

Run on every commit.

pre-commit install

On demand

If you want to run the checks on-demand (outside of git hooks), run:

Run on-demand.

pre-commit run --all-files

The [test harness](TESTING.md) of this git repo uses this approach.

Contributing

Please see [CONTRIBUTING.md](CONTRIBUTING.md).

Testing

Please see [TESTING.md](TESTING.md).

License

The code in this repo is licensed under the [MIT License](LICENSE).