RequireJS monkey patching and dependency graph utils

requirejs-monkey-patch.js

(function(){
	'use strict';

	var DEBUG_DEPENDENCY_GRAPH = true;
	var DEPENDENCY_GRAPH = {};

	function proxyGetter(where, what, from) {
		where.__defineGetter__(what, function() {
			return from[what];
		});
	}
	function proxySetter(where, what, from) {
		where.__defineSetter__(what, function(v) {
			from[what] = v;
		});
	}

	function mimicRealAPI(fnc, handler) {
		for(var prop in fnc) {
			if(typeof fnc[prop] === 'function') {
				handler[prop] = fnc[prop];
			} else {
				proxyGetter(handler, prop, fnc);
				proxySetter(handler, prop, fnc);
			}
		}
		return handler;
	}

	function buildRequireDefineMonkeyPatch(reqDef) {
		return mimicRealAPI(reqDef, function(nameDepsOrHandler, depsOrHandler, handler) {
			var name;
			var deps;

			if(typeof nameDepsOrHandler !== 'function') {
				if(typeof nameDepsOrHandler === 'string') {
					name = nameDepsOrHandler;
					deps = depsOrHandler;
				} else {
					deps = nameDepsOrHandler;
					handler = depsOrHandler;
				}
			}

			if(!!deps && typeof deps !== 'function') {
				// MUTATION NEEDED, CANNOT USE FUNCTIONAL HERE (like filter)
				for(var i = 0; i < deps.length; i++) {
					deps[i] = deps[i].replace('#', '!');
				}

				if(DEBUG_DEPENDENCY_GRAPH) {
					var err = new Error();
					var where = 'UNKNOWN';
					try {
						where = err.stack.split('\n')
							.splice(2)[0]
							.trim()
							.substring(3)
							.replace(window.location.origin, '')
						;
					} catch(e) {
					}

					deps.forEach(function(dep) {
						if(!DEPENDENCY_GRAPH.hasOwnProperty(dep)) {
							DEPENDENCY_GRAPH[dep] = [];
						}
						if(DEPENDENCY_GRAPH[dep].indexOf(where) === -1) {
							DEPENDENCY_GRAPH[dep].push(where);
						}
					});
				}

			}
			return reqDef.apply(this, arguments);
		});
	}

	window.define = buildRequireDefineMonkeyPatch(window.define);
	window.require = buildRequireDefineMonkeyPatch(window.require);
	window.requirejs = buildRequireDefineMonkeyPatch(window.requirejs);

	if(DEBUG_DEPENDENCY_GRAPH) {
		window.DEPENDENCY_GRAPH = DEPENDENCY_GRAPH;
		window.findDep = function(dep) {
			var retObj = {};
			var r = new RegExp('.*' + dep + '.*');

			Object.keys(window.DEPENDENCY_GRAPH)
				.filter(function(itm) {
					return r.test(itm);
				})
				.forEach(function(depName) {
					retObj[depName] = DEPENDENCY_GRAPH[depName];
				})
			;
			return retObj;
		};
		window.console.log('%cYou can check the Dependecy Graph, available as window.DEPENDENCY_GRAPH, also search for dependencies by window.findDep(searchStr);', 'background: black; color: orange; font-size: 26px;');
	}

})();