Catch common typos on scope methods

[OverZealous]

One of the more annoying typos that comes up is calling scope.watch instead of scope.$watch.

It would be nice to disallow calling any of the common scope methods on scope, $scope, or $rootScope without the appropriate $ prefix.

Only on these objects:

• $scope
• scope
• $rootScope

These method names are invalid:

• new
• watch
• watchGroup
• watchCollection
• digest
• destroy
• eval
• evalAsync
• apply
• applyAsync
• on
• emit
• broadcast

Similarly, it would be nice to error if someone types in scope.$on('destroy', ...) instead of scope.$on('$destroy', ...).

[remcohaszing]

Actually, assigning custom methods onto $scope or $rootScope is probably always a bad idea. No matter if it's called watch, $witch or witch. I think this is already handled by the controller-as rule.

If any of the typos described exists, I think this should be caught by a unittest, not a linter.

Also, I think this (silly) example is still valid:

/**
 * Bind a handler for the event of the user watching this element.
 */
.directive('watch', function() {
  return {
    scope: {
      watch: '&'
    },
    link: function link(scope, element) {
      element.on('watch', function(event) {
        scope.on(event);
      });
    }
  };
})

[OverZealous]

@remcohaszing That response doesn't make any sense to me.

This isn't about assigning, this is about catching common typos on scope methods. For example, it's easy to accidentally type scope.on('someEvent') rather than scope.$on('someEvent'). This is just an annoyance, and sounds like the specific use case for a linter. It's nice to catch the bug early on.

The controller-as method both is too restrictive (simple directives don't always need a controller), and solving the wrong issue.

I don't see how unit tests come into play at all; that argument could pretty much be used for anything a linter does.