Added .missingPermissions() (#756)

* Added .missingPermissions()

* Added .missingPermissions()

* Fixed docs for .missingPermissions()

* Fixed Travis CI trailing spaces?

* Fixed Travis CI trailing spaces?

src/structures/EvaluatedPermissions.js

@@ -52,6 +52,16 @@ class EvaluatedPermissions {
   hasPermissions(permissions, explicit = false) {
     return permissions.map(p => this.hasPermission(p, explicit)).every(v => v);
   }
+
+  /**
+   * Checks whether the user has all specified permissions, and lists any missing permissions.
+   * @param {PermissionResolvable[]} permissions The permissions to check for
+   * @param {boolean} [explicit=false] Whether to require the user to explicitly have the exact permissions
+   * @returns {array}
+   */
+  missingPermissions(permissions, explicit = false) {
+    return permissions.filter(p => !this.hasPermission(p, explicit));
+  }
 }
 
 module.exports = EvaluatedPermissions;

src/structures/GuildMember.js

@@ -253,6 +253,16 @@ class GuildMember {
     return permissions.map(p => this.hasPermission(p, explicit)).every(v => v);
   }
 
+  /**
+   * Checks whether the roles of the member allows them to perform specific actions, and lists any missing permissions.
+   * @param {PermissionResolvable[]} permissions The permissions to check for
+   * @param {boolean} [explicit=false] Whether to require the member to explicitly have the exact permissions
+   * @returns {array}
+   */
+  missingPermissions(permissions, explicit = false) {
+    return permissions.filter(p => !this.hasPermission(p, explicit));
+  }
+
   /**
    * Edit a Guild Member
    * @param {GuildmemberEditData} data The data to edit the member with