CI: Added .editorconfig linting

.editorconfig

@@ -1,16 +1,33 @@
 # This file is for unifying the coding style for different editors and IDEs
 # editorconfig.org
-
-# PHP PSR-2 Coding Standards
-# http://www.php-fig.org/psr/psr-2/
+# https://github.com/editorconfig/specification/blob/master/index.rst
 
 root = true
 
-[*.php]
+[*]
 charset = utf-8
 end_of_line = lf
+indent_style = space
 insert_final_newline = true
 trim_trailing_whitespace = true
-indent_style = space
+max_line_length = 120
+
+[*.md]
+trim_trailing_whitespace = false
+
+[*.php]
 indent_size = 4
 
+[*.{js,css,less,sass,scss}]
+indent_size = 2
+
+[*.{yml,yaml}]
+indent_size = 2
+
+[*.mo]
+charset = unset
+end_of_line = unset
+indent_style = unset
+indent_size = unset
+insert_final_newline = unset
+trim_trailing_whitespace = unset

.gitlab-ci.yml

@@ -35,6 +35,12 @@ check-style:
   script:
     - phpcs -p --no-colors --basepath="$PWD"
 
+check-editorconfig:
+  image: mstruebing/editorconfig-checker
+  stage: validate
+  script:
+    - ec -v
+
 validate-composer:
   image: composer:latest
   stage: validate

CONTRIBUTING.md

@@ -1,7 +1,7 @@
 # Contributing
 ## Coding guide lines
-* Make sure you code follows the [PSR-12](https://www.php-fig.org/psr/psr-12/) code style.
-  You may use `composer run phpcs` to verify that.
+* Make sure your code follows the [PSR-12](https://www.php-fig.org/psr/psr-12/) code style and is [.editorconfig](.editorconfig) valid.
+  You may use `composer run phpcs` and [Editorconfig-Checker](https://editorconfig-checker.github.io) to verify that.
 * Use `use` statements wherever possible instead of writing the fully qualified name.
 * Order the composer/npm dependencies alphabetically.
 * Do not use code from the [includes](./includes) directory anywhere else.