{"action":"created","issue":{"url":"https://api.github.com/repos/ckeditor/ckeditor5-design/issues/84","repository_url":"https://api.github.com/repos/ckeditor/ckeditor5-design","labels_url":"https://api.github.com/repos/ckeditor/ckeditor5-design/issues/84/labels{/name}","comments_url":"https://api.github.com/repos/ckeditor/ckeditor5-design/issues/84/comments","events_url":"https://api.github.com/repos/ckeditor/ckeditor5-design/issues/84/events","html_url":"https://github.com/ckeditor/ckeditor5-design/issues/84","id":115033107,"number":84,"title":"Protected and private methods.","user":{"login":"scofalik","id":1502228,"avatar_url":"https://avatars.githubusercontent.com/u/1502228?v=3","gravatar_id":"","url":"https://api.github.com/users/scofalik","html_url":"https://github.com/scofalik","followers_url":"https://api.github.com/users/scofalik/followers","following_url":"https://api.github.com/users/scofalik/following{/other_user}","gists_url":"https://api.github.com/users/scofalik/gists{/gist_id}","starred_url":"https://api.github.com/users/scofalik/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/scofalik/subscriptions","organizations_url":"https://api.github.com/users/scofalik/orgs","repos_url":"https://api.github.com/users/scofalik/repos","events_url":"https://api.github.com/users/scofalik/events{/privacy}","received_events_url":"https://api.github.com/users/scofalik/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/ckeditor/ckeditor5-design/labels/review?","name":"review?","color":"207de5"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":14,"created_at":"2015-11-04T11:29:46Z","updated_at":"2016-02-09T10:34:06Z","closed_at":null,"body":"I'd like to discuss private and protected methods.\r\n\r\n1. What are they?\r\n2. How we define them?\r\n3. How we document them?\r\n4. If and how we test them?\r\n\r\n---\r\n\r\n1. From what I understand, general consensus right now is that, for us:\r\n  * Protected method is a method that is used by the class and also other classes in their internal mechanisms but should not be used by users. Protected method is inherited by derived class.\r\n  * Private method is a method used only by the class and there is no need to for it to be public, even for internal mechanisms of other classes. Something like a helper function, that wraps/organizes a part of code.\r\n\r\n2. Both protected and private methods should start their name with underscore.\r\n  * Since protected method has to be available for other classes we define them in class scope:\r\n  ```javascript\r\n  class Foo {\r\n      /**\r\n       * This method is protected.\r\n       * @protected\r\n       */\r\n      _protectedMethod() { }\r\n  }\r\n  ```\r\n  * Since we actively do not want other parts of code to use private functions, we can and should define them outside of class scope:\r\n  ```javascript\r\n  class Foo {\r\n      // ...\r\n      myFunc( a ) {\r\n          // ...\r\n          a = _privateMethod( a );\r\n          // ..\r\n      }\r\n  }\r\n  \r\n  /**\r\n   * This method is private\r\n   * @method _privateMethod\r\n   * @private\r\n   */\r\n  function _privateMethod( a ) {\r\n      // ...\r\n  }\r\n  ```\r\n3. Both protected and private methods should be taggged by an appropriate JSDoc tag (@private and @protected) and documented. We could argue that private methods are used only by the class but still they are used and might need to be expanded or used in other places so I see no reason not to document them. I am for using normaln JSDoc documentation for both protected and private methods.\r\n4. Protected method should be tested as usual, there is no reason why we should not test them. For private methods, I hold an opinion that we don't have to test them, as they are tested by testing functions that use them. We should still get code coverage for them, even if they are not available outside (or am I wrong?)."},"comment":{"url":"https://api.github.com/repos/ckeditor/ckeditor5-design/issues/comments/181806663","html_url":"https://github.com/ckeditor/ckeditor5-design/issues/84#issuecomment-181806663","issue_url":"https://api.github.com/repos/ckeditor/ckeditor5-design/issues/84","id":181806663,"user":{"login":"Reinmar","id":156149,"avatar_url":"https://avatars.githubusercontent.com/u/156149?v=3","gravatar_id":"","url":"https://api.github.com/users/Reinmar","html_url":"https://github.com/Reinmar","followers_url":"https://api.github.com/users/Reinmar/followers","following_url":"https://api.github.com/users/Reinmar/following{/other_user}","gists_url":"https://api.github.com/users/Reinmar/gists{/gist_id}","starred_url":"https://api.github.com/users/Reinmar/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/Reinmar/subscriptions","organizations_url":"https://api.github.com/users/Reinmar/orgs","repos_url":"https://api.github.com/users/Reinmar/repos","events_url":"https://api.github.com/users/Reinmar/events{/privacy}","received_events_url":"https://api.github.com/users/Reinmar/received_events","type":"User","site_admin":false},"created_at":"2016-02-09T10:34:06Z","updated_at":"2016-02-09T10:34:06Z","body":"Actually, I've got a problem with this myself. I found a couple conventions but all which use any underscores use them for protected stuff as well. I guess that this is intended to easily distinguish between stuff that you can touch when using some class (from outside of it – so a typical use case) and stuff that you shouldn't. And it makes sense.\r\n\r\nIf we prefix only private stuff, then it may be confusing. Without look into the docs you won't be sure how to use some class. Especially that popular conventions state that if you use underscores at all, all non-underscored things are public.\r\n\r\nSo, I'd keep the previous convention defining that protected stuff is underscored as well. In my opinion it makes much more sense. I even started feeling that when fixing the code in ckeditor/ckeditor5-core#192, because suddenly methods which were absolutely invalid in terms of the global use looked as global."}}