yamltidy - Automatic cleanup of YAML files

yamltidy is a formatter for YAML files.

It's is inspired by the great tools yamllint and perltidy.

• yamllint checks YAML files and reports errors and warnings.
• perltidy automatically reformats perl programs
• yamltidy automatically reformats YAML files

Usage

    % yamltidy foo.yaml
    ---
    a: # a comment
      b:
        c: d

    # inplace - directly write result into original file
    yamltidy --inplace foo.yaml

Complete documentation of options: yamltidy.pod

Installation

If you don't have a Perl CPAN client to install modules, install cpanminus:

# debian example
% apt-get install cpanminus
# openSUSE
% zypper install perl-App-cpanminus

Install yamltidy

% cpanm YAML::Tidy
# faster without running tests
% cpanm --notest YAML::Tidy

Local installation

If you just want to play with it, but don't want to install it globally on your system, use this:

% cpanm -l ~/localyamltidy YAML::Tidy
% export PERL5LIB=~/localyamltidy/lib/perl5
% PATH=~/localyamltidy/bin:$PATH

Use Container Image

% docker pull perlpunk/yamltidy
% docker run -i --rm perlpunk/yamltidy yamltidy - < in.yaml

Config

The configuration is similar as for yamllint.

It's written in YAML, and it searches for it in these places:

• $PWD/.yamltidy
• ~/.config/yamltidy/config.yaml
• ~/.yamltidy

You can pass the configuration file via the -c/--config-file switch.

The default config:

---
v: v0.1
indentation:
  spaces: 2
  block-sequence-in-mapping: 0
trailing-spaces: fix
header: true
scalar-style:
  default: plain
adjacency: 0

An indentation of two spaces is recommended. Sequences will by default be zero-indented, because the hyphen - counts as indentation. The option block-sequence-in-mapping can influence that.

More detailed information on configuration will follow.

You can find examples for several configurations here: perlpunk.github.io/yamltidy

Utils

Mappings for vim

Type <leader>yt to tidy the whole buffer:

:noremap <leader>yt :%!yamltidy -<CR>

Visually select lines and type <leader>yt. The first level of indentation spaces will be kept.

:vnoremap <leader>yt :!yamltidy --partial -<CR>

Tests

yamltidy tests are using the YAML Test Suite.

The tests currently make sure that at least the yamltidy output semantically matches the input.

Implementation

yamltidy is based on C libyaml and the perl binding YAML::LibYAML::API.