angular - analyse scopes and watchers

gistfile1.js

function analyseScopeAndWatchers() {
    // fetch all elements with ng-scope class
    var scopeElements = Array.prototype.slice.apply(document.querySelectorAll(".ng-scope"));
    
    // map elements to scopes
    var scopes = scopeElements.map(function (element) {
        return angular.element(element).scope();
    });
    
    // filter duplicated scopes created by ng-view
    var scopesById = {};
    var uniqueScopes = [];
    scopes.forEach(function (scope) {
        if (scopesById[scope.$id] === undefined) {
            scopesById[scope.$id] = scope;
            uniqueScopes.push(scope);
        }
    });
    
    // map uniqueScopes to watchers
    var watchers = uniqueScopes.map(function (scope) {
        return scope.$$watchers;
    }).filter(function (watchers) {
        return watchers != null;
    });
    
    // extract the count values
    var watchersCountValues = watchers.map(function (watcher) {
        return watcher.length;
    });
    
    // sum up the length with reduce
    var watchersCount = watchersCountValues.reduce(function(a,b) {
        return a + b;
    });
    
    return {
        watchers: watchers,
        watchersCount: watchersCount,
        uniqueScopes: uniqueScopes
    };
}