Validates .yml locale files for Ruby on Rails projects.

• Rails I18n variables:

  • Make sure users didn't translate the variables (e.g. Hi %{user} was translated to Hola %{usuario}).
  • Make sure users didn't write invalid variable syntax (e.g. {name} or {name}% instead of %{name})

• Make sure users didn't change locked keys (searches for a file named locked_keys in the same folder, where each line is a regular expression).

• Check for bad characters in values (transifex sometimes adds the "⏎ " character)

• Keys that don't appear in the source language

• Checks that Ruby's YAML parser can parse the file

• Checks for missing pluralization (in languages like russian there are 4 types of pluralization: one, other, few, many)

Given the following file tree:

config/
  locales/
    en.yml
    he.yml
    nl.yml
    fr.yml
    ...

Run the following command:

yaml-validator validate config/locales

or 

cd config/locales
yaml-validator

it will validate the files (in reference to en.yml) and show the following types of errors:

he.yml: parent_key.key1 doesn't exist in en.yml
fr.yml: found character that cannot start any token while scanning for the next token at line 19 column 14
nl.yml: parent_key.key1: missing variable 'var_with_typo' (available options var_without_type)

• Added missing translations validation (strings that appear in en.yml but not in the other strings)