--- a/src/js/libs/lab.js Fri Apr 27 19:18:21 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,514 +0,0 @@
-/*! LAB.js (LABjs :: Loading And Blocking JavaScript)
- v2.0.3 (c) Kyle Simpson
- MIT License
-*/
-
-(function(global){
- var _$LAB = global.$LAB,
-
- // constants for the valid keys of the options object
- _UseLocalXHR = "UseLocalXHR",
- _AlwaysPreserveOrder = "AlwaysPreserveOrder",
- _AllowDuplicates = "AllowDuplicates",
- _CacheBust = "CacheBust",
- /*!START_DEBUG*/_Debug = "Debug",/*!END_DEBUG*/
- _BasePath = "BasePath",
-
- // stateless variables used across all $LAB instances
- root_page = /^[^?#]*\//.exec(location.href)[0],
- root_domain = /^\w+\:\/\/\/?[^\/]+/.exec(root_page)[0],
- append_to = document.head || document.getElementsByTagName("head"),
-
- // inferences... ick, but still necessary
- opera_or_gecko = (global.opera && Object.prototype.toString.call(global.opera) == "[object Opera]") || ("MozAppearance" in document.documentElement.style),
-
-/*!START_DEBUG*/
- // console.log() and console.error() wrappers
- log_msg = function(){},
- log_error = log_msg,
-/*!END_DEBUG*/
-
- // feature sniffs (yay!)
- test_script_elem = document.createElement("script"),
- explicit_preloading = typeof test_script_elem.preload == "boolean", // http://wiki.whatwg.org/wiki/Script_Execution_Control#Proposal_1_.28Nicholas_Zakas.29
- real_preloading = explicit_preloading || (test_script_elem.readyState && test_script_elem.readyState == "uninitialized"), // will a script preload with `src` set before DOM append?
- script_ordered_async = !real_preloading && test_script_elem.async === true, // http://wiki.whatwg.org/wiki/Dynamic_Script_Execution_Order
-
- // XHR preloading (same-domain) and cache-preloading (remote-domain) are the fallbacks (for some browsers)
- xhr_or_cache_preloading = !real_preloading && !script_ordered_async && !opera_or_gecko
- ;
-
-/*!START_DEBUG*/
- // define console wrapper functions if applicable
- if (global.console && global.console.log) {
- if (!global.console.error) global.console.error = global.console.log;
- log_msg = function(msg) { global.console.log(msg); };
- log_error = function(msg,err) { global.console.error(msg,err); };
- }
-/*!END_DEBUG*/
-
- // test for function
- function is_func(func) { return Object.prototype.toString.call(func) == "[object Function]"; }
-
- // test for array
- function is_array(arr) { return Object.prototype.toString.call(arr) == "[object Array]"; }
-
- // make script URL absolute/canonical
- function canonical_uri(src,base_path) {
- var absolute_regex = /^\w+\:\/\//;
-
- // is `src` is protocol-relative (begins with // or ///), prepend protocol
- if (/^\/\/\/?/.test(src)) {
- src = location.protocol + src;
- }
- // is `src` page-relative? (not an absolute URL, and not a domain-relative path, beginning with /)
- else if (!absolute_regex.test(src) && src.charAt(0) != "/") {
- // prepend `base_path`, if any
- src = (base_path || "") + src;
- }
- // make sure to return `src` as absolute
- return absolute_regex.test(src) ? src : ((src.charAt(0) == "/" ? root_domain : root_page) + src);
- }
-
- // merge `source` into `target`
- function merge_objs(source,target) {
- for (var k in source) { if (source.hasOwnProperty(k)) {
- target[k] = source[k]; // TODO: does this need to be recursive for our purposes?
- }}
- return target;
- }
-
- // does the chain group have any ready-to-execute scripts?
- function check_chain_group_scripts_ready(chain_group) {
- var any_scripts_ready = false;
- for (var i=0; i<chain_group.scripts.length; i++) {
- if (chain_group.scripts[i].ready && chain_group.scripts[i].exec_trigger) {
- any_scripts_ready = true;
- chain_group.scripts[i].exec_trigger();
- chain_group.scripts[i].exec_trigger = null;
- }
- }
- return any_scripts_ready;
- }
-
- // creates a script load listener
- function create_script_load_listener(elem,registry_item,flag,onload) {
- elem.onload = elem.onreadystatechange = function() {
- if ((elem.readyState && elem.readyState != "complete" && elem.readyState != "loaded") || registry_item[flag]) return;
- elem.onload = elem.onreadystatechange = null;
- onload();
- };
- }
-
- // script executed handler
- function script_executed(registry_item) {
- registry_item.ready = registry_item.finished = true;
- for (var i=0; i<registry_item.finished_listeners.length; i++) {
- registry_item.finished_listeners[i]();
- }
- registry_item.ready_listeners = [];
- registry_item.finished_listeners = [];
- }
-
- // make the request for a scriptha
- function request_script(chain_opts,script_obj,registry_item,onload,preload_this_script) {
- // setTimeout() "yielding" prevents some weird race/crash conditions in older browsers
- setTimeout(function(){
- var script, src = script_obj.real_src, xhr;
-
- // don't proceed until `append_to` is ready to append to
- if ("item" in append_to) { // check if `append_to` ref is still a live node list
- if (!append_to[0]) { // `append_to` node not yet ready
- // try again in a little bit -- note: will re-call the anonymous function in the outer setTimeout, not the parent `request_script()`
- setTimeout(arguments.callee,25);
- return;
- }
- // reassign from live node list ref to pure node ref -- avoids nasty IE bug where changes to DOM invalidate live node lists
- append_to = append_to[0];
- }
- script = document.createElement("script");
- if (script_obj.type) script.type = script_obj.type;
- if (script_obj.charset) script.charset = script_obj.charset;
-
- // should preloading be used for this script?
- if (preload_this_script) {
- // real script preloading?
- if (real_preloading) {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("start script preload: "+src);/*!END_DEBUG*/
- registry_item.elem = script;
- if (explicit_preloading) { // explicit preloading (aka, Zakas' proposal)
- script.preload = true;
- script.onpreload = onload;
- }
- else {
- script.onreadystatechange = function(){
- if (script.readyState == "loaded") onload();
- };
- }
- script.src = src;
- // NOTE: no append to DOM yet, appending will happen when ready to execute
- }
- // same-domain and XHR allowed? use XHR preloading
- else if (preload_this_script && src.indexOf(root_domain) == 0 && chain_opts[_UseLocalXHR]) {
- xhr = new XMLHttpRequest(); // note: IE never uses XHR (it supports true preloading), so no more need for ActiveXObject fallback for IE <= 7
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("start script preload (xhr): "+src);/*!END_DEBUG*/
- xhr.onreadystatechange = function() {
- if (xhr.readyState == 4) {
- xhr.onreadystatechange = function(){}; // fix a memory leak in IE
- registry_item.text = xhr.responseText + "\n//@ sourceURL=" + src; // http://blog.getfirebug.com/2009/08/11/give-your-eval-a-name-with-sourceurl/
- onload();
- }
- };
- xhr.open("GET",src);
- xhr.send();
- }
- // as a last resort, use cache-preloading
- else {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("start script preload (cache): "+src);/*!END_DEBUG*/
- script.type = "text/cache-script";
- create_script_load_listener(script,registry_item,"ready",function() {
- append_to.removeChild(script);
- onload();
- });
- script.src = src;
- append_to.insertBefore(script,append_to.firstChild);
- }
- }
- // use async=false for ordered async? parallel-load-serial-execute http://wiki.whatwg.org/wiki/Dynamic_Script_Execution_Order
- else if (script_ordered_async) {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("start script load (ordered async): "+src);/*!END_DEBUG*/
- script.async = false;
- create_script_load_listener(script,registry_item,"finished",onload);
- script.src = src;
- append_to.insertBefore(script,append_to.firstChild);
- }
- // otherwise, just a normal script element
- else {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("start script load: "+src);/*!END_DEBUG*/
- create_script_load_listener(script,registry_item,"finished",onload);
- script.src = src;
- append_to.insertBefore(script,append_to.firstChild);
- }
- },0);
- }
-
- // create a clean instance of $LAB
- function create_sandbox() {
- var global_defaults = {},
- can_use_preloading = real_preloading || xhr_or_cache_preloading,
- queue = [],
- registry = {},
- instanceAPI
- ;
-
- // global defaults
- global_defaults[_UseLocalXHR] = true;
- global_defaults[_AlwaysPreserveOrder] = false;
- global_defaults[_AllowDuplicates] = false;
- global_defaults[_CacheBust] = false;
- /*!START_DEBUG*/global_defaults[_Debug] = false;/*!END_DEBUG*/
- global_defaults[_BasePath] = "";
-
- // execute a script that has been preloaded already
- function execute_preloaded_script(chain_opts,script_obj,registry_item) {
- var script;
-
- function preload_execute_finished() {
- if (script != null) { // make sure this only ever fires once
- script = null;
- script_executed(registry_item);
- }
- }
-
- if (registry[script_obj.src].finished) return;
- if (!chain_opts[_AllowDuplicates]) registry[script_obj.src].finished = true;
-
- script = registry_item.elem || document.createElement("script");
- if (script_obj.type) script.type = script_obj.type;
- if (script_obj.charset) script.charset = script_obj.charset;
- create_script_load_listener(script,registry_item,"finished",preload_execute_finished);
-
- // script elem was real-preloaded
- if (registry_item.elem) {
- registry_item.elem = null;
- }
- // script was XHR preloaded
- else if (registry_item.text) {
- script.onload = script.onreadystatechange = null; // script injection doesn't fire these events
- script.text = registry_item.text;
- }
- // script was cache-preloaded
- else {
- script.src = script_obj.real_src;
- }
- append_to.insertBefore(script,append_to.firstChild);
-
- // manually fire execution callback for injected scripts, since events don't fire
- if (registry_item.text) {
- preload_execute_finished();
- }
- }
-
- // process the script request setup
- function do_script(chain_opts,script_obj,chain_group,preload_this_script) {
- var registry_item,
- registry_items,
- ready_cb = function(){ script_obj.ready_cb(script_obj,function(){ execute_preloaded_script(chain_opts,script_obj,registry_item); }); },
- finished_cb = function(){ script_obj.finished_cb(script_obj,chain_group); }
- ;
-
- script_obj.src = canonical_uri(script_obj.src,chain_opts[_BasePath]);
- script_obj.real_src = script_obj.src +
- // append cache-bust param to URL?
- (chain_opts[_CacheBust] ? ((/\?.*$/.test(script_obj.src) ? "&_" : "?_") + ~~(Math.random()*1E9) + "=") : "")
- ;
-
- if (!registry[script_obj.src]) registry[script_obj.src] = {items:[],finished:false};
- registry_items = registry[script_obj.src].items;
-
- // allowing duplicates, or is this the first recorded load of this script?
- if (chain_opts[_AllowDuplicates] || registry_items.length == 0) {
- registry_item = registry_items[registry_items.length] = {
- ready:false,
- finished:false,
- ready_listeners:[ready_cb],
- finished_listeners:[finished_cb]
- };
-
- request_script(chain_opts,script_obj,registry_item,
- // which callback type to pass?
- (
- (preload_this_script) ? // depends on script-preloading
- function(){
- registry_item.ready = true;
- for (var i=0; i<registry_item.ready_listeners.length; i++) {
- registry_item.ready_listeners[i]();
- }
- registry_item.ready_listeners = [];
- } :
- function(){ script_executed(registry_item); }
- ),
- // signal if script-preloading should be used or not
- preload_this_script
- );
- }
- else {
- registry_item = registry_items[0];
- if (registry_item.finished) {
- finished_cb();
- }
- else {
- registry_item.finished_listeners.push(finished_cb);
- }
- }
- }
-
- // creates a closure for each separate chain spawned from this $LAB instance, to keep state cleanly separated between chains
- function create_chain() {
- var chainedAPI,
- chain_opts = merge_objs(global_defaults,{}),
- chain = [],
- exec_cursor = 0,
- scripts_currently_loading = false,
- group
- ;
-
- // called when a script has finished preloading
- function chain_script_ready(script_obj,exec_trigger) {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("script preload finished: "+script_obj.real_src);/*!END_DEBUG*/
- script_obj.ready = true;
- script_obj.exec_trigger = exec_trigger;
- advance_exec_cursor(); // will only check for 'ready' scripts to be executed
- }
-
- // called when a script has finished executing
- function chain_script_executed(script_obj,chain_group) {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("script execution finished: "+script_obj.real_src);/*!END_DEBUG*/
- script_obj.ready = script_obj.finished = true;
- script_obj.exec_trigger = null;
- // check if chain group is all finished
- for (var i=0; i<chain_group.scripts.length; i++) {
- if (!chain_group.scripts[i].finished) return;
- }
- // chain_group is all finished if we get this far
- chain_group.finished = true;
- advance_exec_cursor();
- }
-
- // main driver for executing each part of the chain
- function advance_exec_cursor() {
- while (exec_cursor < chain.length) {
- if (is_func(chain[exec_cursor])) {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_msg("$LAB.wait() executing: "+chain[exec_cursor]);/*!END_DEBUG*/
- try { chain[exec_cursor++](); } catch (err) {
- /*!START_DEBUG*/if (chain_opts[_Debug]) log_error("$LAB.wait() error caught: ",err);/*!END_DEBUG*/
- }
- continue;
- }
- else if (!chain[exec_cursor].finished) {
- if (check_chain_group_scripts_ready(chain[exec_cursor])) continue;
- break;
- }
- exec_cursor++;
- }
- // we've reached the end of the chain (so far)
- if (exec_cursor == chain.length) {
- scripts_currently_loading = false;
- group = false;
- }
- }
-
- // setup next chain script group
- function init_script_chain_group() {
- if (!group || !group.scripts) {
- chain.push(group = {scripts:[],finished:true});
- }
- }
-
- // API for $LAB chains
- chainedAPI = {
- // start loading one or more scripts
- script:function(){
- for (var i=0; i<arguments.length; i++) {
- (function(script_obj,script_list){
- var splice_args;
-
- if (!is_array(script_obj)) {
- script_list = [script_obj];
- }
- for (var j=0; j<script_list.length; j++) {
- init_script_chain_group();
- script_obj = script_list[j];
-
- if (is_func(script_obj)) script_obj = script_obj();
- if (!script_obj) continue;
- if (is_array(script_obj)) {
- // set up an array of arguments to pass to splice()
- splice_args = [].slice.call(script_obj); // first include the actual array elements we want to splice in
- splice_args.unshift(j,1); // next, put the `index` and `howMany` parameters onto the beginning of the splice-arguments array
- [].splice.apply(script_list,splice_args); // use the splice-arguments array as arguments for splice()
- j--; // adjust `j` to account for the loop's subsequent `j++`, so that the next loop iteration uses the same `j` index value
- continue;
- }
- if (typeof script_obj == "string") script_obj = {src:script_obj};
- script_obj = merge_objs(script_obj,{
- ready:false,
- ready_cb:chain_script_ready,
- finished:false,
- finished_cb:chain_script_executed
- });
- group.finished = false;
- group.scripts.push(script_obj);
-
- do_script(chain_opts,script_obj,group,(can_use_preloading && scripts_currently_loading));
- scripts_currently_loading = true;
-
- if (chain_opts[_AlwaysPreserveOrder]) chainedAPI.wait();
- }
- })(arguments[i],arguments[i]);
- }
- return chainedAPI;
- },
- // force LABjs to pause in execution at this point in the chain, until the execution thus far finishes, before proceeding
- wait:function(){
- if (arguments.length > 0) {
- for (var i=0; i<arguments.length; i++) {
- chain.push(arguments[i]);
- }
- group = chain[chain.length-1];
- }
- else group = false;
-
- advance_exec_cursor();
-
- return chainedAPI;
- }
- };
-
- // the first chain link API (includes `setOptions` only this first time)
- return {
- script:chainedAPI.script,
- wait:chainedAPI.wait,
- setOptions:function(opts){
- merge_objs(opts,chain_opts);
- return chainedAPI;
- }
- };
- }
-
- // API for each initial $LAB instance (before chaining starts)
- instanceAPI = {
- // main API functions
- setGlobalDefaults:function(opts){
- merge_objs(opts,global_defaults);
- return instanceAPI;
- },
- setOptions:function(){
- return create_chain().setOptions.apply(null,arguments);
- },
- script:function(){
- return create_chain().script.apply(null,arguments);
- },
- wait:function(){
- return create_chain().wait.apply(null,arguments);
- },
-
- // built-in queuing for $LAB `script()` and `wait()` calls
- // useful for building up a chain programmatically across various script locations, and simulating
- // execution of the chain
- queueScript:function(){
- queue[queue.length] = {type:"script", args:[].slice.call(arguments)};
- return instanceAPI;
- },
- queueWait:function(){
- queue[queue.length] = {type:"wait", args:[].slice.call(arguments)};
- return instanceAPI;
- },
- runQueue:function(){
- var $L = instanceAPI, len=queue.length, i=len, val;
- for (;--i>=0;) {
- val = queue.shift();
- $L = $L[val.type].apply(null,val.args);
- }
- return $L;
- },
-
- // rollback `[global].$LAB` to what it was before this file was loaded, the return this current instance of $LAB
- noConflict:function(){
- global.$LAB = _$LAB;
- return instanceAPI;
- },
-
- // create another clean instance of $LAB
- sandbox:function(){
- return create_sandbox();
- }
- };
-
- return instanceAPI;
- }
-
- // create the main instance of $LAB
- global.$LAB = create_sandbox();
-
-
- /* The following "hack" was suggested by Andrea Giammarchi and adapted from: http://webreflection.blogspot.com/2009/11/195-chars-to-help-lazy-loading.html
- NOTE: this hack only operates in FF and then only in versions where document.readyState is not present (FF < 3.6?).
-
- The hack essentially "patches" the **page** that LABjs is loaded onto so that it has a proper conforming document.readyState, so that if a script which does
- proper and safe dom-ready detection is loaded onto a page, after dom-ready has passed, it will still be able to detect this state, by inspecting the now hacked
- document.readyState property. The loaded script in question can then immediately trigger any queued code executions that were waiting for the DOM to be ready.
- For instance, jQuery 1.4+ has been patched to take advantage of document.readyState, which is enabled by this hack. But 1.3.2 and before are **not** safe or
- fixed by this hack, and should therefore **not** be lazy-loaded by script loader tools such as LABjs.
- */
- (function(addEvent,domLoaded,handler){
- if (document.readyState == null && document[addEvent]){
- document.readyState = "loading";
- document[addEvent](domLoaded,handler = function(){
- document.removeEventListener(domLoaded,handler,false);
- document.readyState = "complete";
- },false);
- }
- })("addEventListener","DOMContentLoaded");
-
-})(this);
\ No newline at end of file