I have a custom post type named ÷project÷ which has `'capability_type' => 'post'` while registering using ÷register_post_type÷.

in my theme files and also functions.php file, I have situations where I should check if the project to be edited is authored by the user or not. so I use this:  

    if ( !current_user_can( 'edit_post', $porject_id ) ) return;
where `$project_id` is post id of the project to be edited. for example I have a page template named `single_project.php` where I can show single posts in project post type to users and I want these people can see each project single page:  

 1. administrators
 2. editors
 3. the contributer (post author)

but using the above code, It is ok with administrators and editors, while not for the contributer himself!

when I use `var_dump( current_user_can( 'edit_post', $project_id ) )` with the contributer logged-in account, it returns `false`, while `var_dump( current_user_can( 'edit_posts' ) )` (with trailing `'s'`) returns `true` (but for every post, not just does for him).  

**Any help with this ??!**