Develop Reference

How to debug timed out waiting for asynchronous Angular tasks? Failure to find elements on angular page occurring

Edit: Note that I found the root of my problem after help from #ernst-zwingli, so if you have this same error one of his noted fixes might help you out. My problem is a known issue with Protractor itself, if you think this may be you, I've expanded on my steps to pinpoint the root of the problem after my original question.
I'm trying to use Protractor in an Angular2 (just Angular) application built using angular-cli.
My problem: Elements on an Angular app page are not being found when browser.waitForAngularEnabledis at it's default setting of true (as in 'I believe I am on an angular page and would like for Protractor to do it's magic'). They are being found just fine if I set browser.waitForAngularEnabledto false (as in 'I am not on an angular page and would like to handle this myself, take a seat Protractor'). How do I track down what's causing this on my definitely Angular pages?
I have a product with a non-Angular Auth0 login page that gates access to the rest of the product that is written in Angular (Angular 4.3.2 to be exact). I have successfully traversed logging in on the non-Angular login page. I flipped the waitForAngularEnabled switched to false to facilitate the non-Angular login. I turned it back to true at the point where I expected my initial landing page (Angular) to be loaded, after clicking the submit button. Code is as follows:
browser.waitForAngularEnabled(false);
browser.driver.get('https://dashboard.net/projects');
browser.driver.sleep(10000);
browser.driver.findElement(By.css("[type='email']"));
browser.driver.findElement(By.css("[type='email']")).sendKeys("email#example.com");
browser.driver.findElement(By.css(".auth0-label-submit")).click();
browser.driver.findElement(By.id("passwordInput")).sendKeys("password");
browser.driver.findElement(By.id("submitButton")).click();
browser.driver.sleep(5000); // needed if not waiting for Angular
//browser.waitForAngularEnabled(true); // Back to Protractor land we go
let elementToFind = element(by.className("header-text"));
elementToFind.isDisplayed().then(function() {grabTheDarnLocalStorage()});
expect(elementToFind.isDisplayed()).toBeTruthy();
If I uncomment the browser.waitForAngularEnabled(true); line to state that I'm back in Angular code I get the error trace as follows:
Failed: Timed out waiting for asynchronous Angular tasks to finish after 30 seconds. This may be because the current page is not an Angular application. Please see the FAQ for more details: https://github.com/angular/protractor/blob/master/docs/timeouts.md#waiting-for-angular
While waiting for element with locator - Locator: By(css selector, .header-text)
ScriptTimeoutError: asynchronous script timeout: result was not received in 30 seconds
(Session info: chrome=61.0.3163.100)
(Driver info: chromedriver=2.32.498550 (9dec58e66c31bcc53a9ce3c7226f0c1c5810906a),platform=Windows NT 10.0.14393 x86_64)
at WebDriverError (C:\Users\c-shouston\AppData\Roaming\npm\node_modules\protractor\node_modules\selenium-webdriver\lib\error.js:27:5)
at ScriptTimeoutError (C:\Users\c-shouston\AppData\Roaming\npm\node_modules\protractor\node_modules\selenium-webdriver\lib\error.js:203:5)
at Object.checkLegacyResponse (C:\Users\c-shouston\AppData\Roaming\npm\node_modules\protractor\node_modules\selenium-webdriver\lib\error.js:505:15)
at parseHttpResponse (C:\Users\c-shouston\AppData\Roaming\npm\node_modules\protractor\node_modules\selenium-webdriver\lib\http.js:509:13)
at doSend.then.response (C:\Users\c-shouston\AppData\Roaming\npm\node_modules\protractor\node_modules\selenium-webdriver\lib\http.js:440:13)
at process._tickCallback (internal/process/next_tick.js:109:7)
From: Task: Protractor.waitForAngular() - Locator: By(css selector, .header-text)
I've referenced the FAQ: https://github.com/angular/protractor/blob/master/docs/timeouts.md#waiting-for-angular
I have my devs stating that they don't use $timeout (they use (Edit: NOT $interval) Observable Interval thank you very much) and they're not sure about $http.
I found this solution about the canonical way to debug protractor Angular sync issue issue: Canonical way to debug Protractor-to-Angular sync issues
but I'm not sure the solution works without access to modifying the dev code to run the programmatic tracker. (Edit: I never did figure out how to get this to work)
I also found this about a long timeout you add before each test, but I feel this is unnecessary overhead that makes your overall test execution take longer than it should without understanding the root cause of the problem: https://stackoverflow.com/a/37217167/2718402 (Edit: yeah, this is a bad idea and adds unnecessary time to your tests, please don't do this)
The frustrating bit is that this seems to be a common occurrence and there doesn't seem to be a streamlined documentation on how to deal with it. Logging in with a non-Angular page only to transition to an Angular page. Angular pages not being picked up properly by Protractor. All of the examples I find online are bits of code that I don't have a reference for where they should be at in my overall test framework. I would kill for a full example of someone testing a non-Angular login that transitions to a fully Angular website, with a setup config and real world test cases. (Edit: This is still true, but I can't make one myself as my application is in a bad grey area, note my RCA below for more details.)
I just want the ability to do my login and then successfully transition over to my Angular pages and be able to rely on Protractor to work with my Angular pages. I need to know what to look for that may be a long running asynchronous process (What specifically can I check for in the Chrome dev tools?). I would love to understand what Protractor needs as defaults in order to successfully work with the Angular parts of my app/website (Is there something beyond the presence of <app-root _nghost-c0="" ng-version="4.3.2"> in the HTML?). Before this job I worked in Java, so all of this asynchronicity and Angular is new to me, so I know I'm missing the known things that a seasoned Javascript dev is aware of.
My Solution/Root Cause Analysis
Starting down the list suggested by #ernst-zwingli:
for Angular(2) Check if the object window.getAllAngularRootElements returns at least one value.
It returned at least one value, so I moved on.
useAllAngular2AppRoots: true,
I tried this and still ran into the async timeout.
And if $interval or other long lasting asynchronous tasks are used, there can be issues, because of the zones
Previously #ernst-zwingli also mentioned looking at the testability method, except it was the old way. Through research and testing I found the window object also has a getAllAngularTestabilities method. This led down an interesting rabbit hole. An example output from the Chrome console (put window.getAllAngularTestabilities() in the Chrome console window, look at the resulting list) is as follows:
t:
_callbacks:...,
_didWork:true,
_isZoneStable: true (this looks promising, but why isn't Protractor working then?!?)
_ngZone:
hasPendingMacrotasks: true,
hasPendingMicrotasks: false,
isStable: true
I would think isZoneStable would be enough, but apparently not so for Protractor. Then looking at Macrotasks being true, I had to look up what the heck a Macrotask was: What does hasPendingMacrotasks and hasPendingMicrotasks check for?.
A macrotask can be:
i.e. setTimeout, setInterval, setImmediate
Thus #ernst-zwingli's note about interval's causing problems in the zones was remembered and something finally clicked.
First github issue, about zone instability
Another github issue complaining about the necessity of using browser.driver to get things done along with browser.waitForAngularEnabled. Apparently this is expected behavior, it led me to issue #3349
Issue #3349 - The actual root cause of my issue. My developers do not actively jump in and out of zones around observables. Even though these observables only have one subscriber. Since they live in the angular zone at this time, they are a long running "Macrotask" that Protractor waits infinitely on.
I can't rewrite the code with these wrappers as I am not currently versed enough in Angular to do it safely and we are currently hurtling toward a November deadline. I think I'll have to deal with using browser.driver for the time being and hope I can't get it fixed later. Hopefully my RCA was helpful for you.

In the following I list a set of potential causes and possibilities to fix/resolve them.
How does AngularJS and Angular(2) Work / What can I check in the Browser Dev Mode
I can't explain it as well as Andrey Agibalov in his Blog here, so check it out (also for developers).
Basically, the objects required by Protractor you can check in your Chrome Dev.
for AngularJS
Check if the object window.angular is properly defined, i.e. lookup window.angular.version and also try window.angular.getTestability of your Root element
for Angular(2)
Check if the object window.getAllAngularRootElements returns at least one value.
Root Element (AngularJS)
Potentially your Angular App is somewhere wrapped within the Body as something like <div ng-app="my-app">.
In that case, you must adjust your rootElement: body inside config.ts. Check this answer for details.
Angular(2)
If you're using Angular (aka Angular2), then there are ngZone's introduced. In this case your config.js should additionally contain this:
exports.config = {
framework: 'jasmine',
seleniumAddress: 'http://localhost:4444/wd/hub',
specs: ['spec.js'],
useAllAngular2AppRoots: true,
// rootElement: 'root-element'
};
check in your browser for window.getAllAngularRootElements as the additional line in conf.js is about this.
If you can, maybe use the advantage of multiple zones possible. Create a 2nd zone, configure rootElement: 'root-element'
to only focus on one zone and then move some asynchronous tasks into the other zone until you found, which task(s) lead to timeout. Keep those tasks (if possible) in the separate zone, so Protractor ignores those tasks.
And if $interval or other long lasting asynchronous tasks are used, there can be issues, because of the zones. Repeatedly or long lasting tasks should be started outside the zone and then be moved into the zone as else Protractor could run into timeouts. There is a workaround for developers to apply, in order to avoid these problems for Protractor.
read all about it here
browser.driver. - side remark
browser.driver.get() works as if ignoreSynchronization = true, since you directly assign the Browser Driver and you kind of bypass the synchronization logic of Protractor.
Read more about it in this answer here.
Hope I could give you some more input and you can solve your issue. Please let me know the results.

Could you please set
browser.ignoreSynchronization = true;
and try

Is there a way to tell Google Closure Compiler to *NOT* inline my local functions?

Here's what I'm looking for:
I want to use the wonderful features of SIMPLE mode minification while disabling just one specific feature (disable local function inline).
UPDATE: The answer is NO, it's not possible given my setup. But for me there is a workaround given I am using Grails.
As #Chad has explained below, "This violates core assumptions of the compiler". See my UPDATE3 below for more info.
IN QUESTION FORM:
I'm using CompilationLevel.SIMPLE_OPTIMIZATIONS which does everything I want, except that it's inlining my local functions.
Is there any way around this? For example, is there a setting I can place in my JS files to tell Google Closure not to inline my local functions?
It would be cool to have some directives at the top of my javascript file such as:
// This is a JS comment...
// google.closure.compiler = [inlineLocalFunctions: false]
I'm developing a Grails app and using the Grails asset-pipeline plugin, which uses Google Closure Compiler (hereafter, Compiler). The plugin supports the different minification levels that Compiler supports via the Grails config grails.assets.minifyOptions. This allows for 'SIMPLE', 'ADVANCED', 'WHITESPACE_ONLY'.
AssetCompiler.groovy (asset-pipeline plugin) calls ClosureCompilerProcessor.process()
That eventually assigns SIMPLE_OPTIMIZATIONS on the CompilerOptions object. And by doing so, CompilerOptions.inlineLocalFunctions = true as a byproduct (this is hard coded behavior in Compiler). If I were to use WHITESPACE_ONLY the result would be inlineLocalFunctions=false.
So by using Asset Pipeline's 'SIMPLE' setting, local functions are being inlined and that is causing me trouble. Example: ExtJS ext-all-debug.js which uses lots of local functions.
SO post Is it possible to make Google Closure compiler *not* inline certain functions? provides some help. I can use its window['dontBlowMeAway'] = dontBlowMeAway trick to keep my functions from inlining. However I have LOTS of functions and I'm not about to manually do this for each one; nor would I want to write a script to do it for me. Creating a JS model and trying to identity local functions doesn't sound safe, fun nor fast.
The previous SO post directs the reader to https://developers.google.com/closure/compiler/docs/api-tutorial3#removal, where the window['bla'] trick is explained, and it works.
Wow thanks for reading this long.
Help? :-)
UPDATE1:
Okay. While spending all the effort in writing this question, I may have a trick that could work. Grails uses Groovy. Groovy makes method call interception easy using its MetaClass API.
I'm going to try intercepting the call to:
com.google.javascript.jscomp.Compiler.compile(
List<T1> externs, List<T2> inputs, CompilerOptions options)
My intercepting method will look like:
options.inlineLocalFunctions=false
// Then delegate call to the real compile() method
It's bed time so I'll have to try this later. Even so, it would be nice to solve this without a hack.
UPDATE2:
The response in a similar post (Is it possible to make Google Closure compiler *not* inline certain functions?) doesn't resolve my problem because of the large quantity of functions I need inlined. I've already explained this point.
Take the ExtJS file I cited above as an example of why the above similar SO post doesn't resolve my problem. Look at the raw code for ext-all-debug.js. Find the byAttribute() function. Then keep looking for the string "byAttribute" and you'll see that it is part of strings that are being defined. I am not familiar with this code, but I'm supposing that these string-based values of byAttribute are later being passed to JS's eval() function for execution. Compiler does not alter these values of byAttribute when it's part of a string. Once function byAttribute is inlined, attempts to call the function is no longer possible.
UPDATE3: I attempted two strategies to resolve this problem and both proved unsuccessful. However, I successfully implemented a workaround. My failed attempts:
Use Groovy method interception (Meta Object Protocol, aka MOP) to intercept com.google.javascript.jscomp.Compiler.compile().
Fork the closure-compiler.jar (make my own custom copy) and modify com.google.javascript.jscomp.applySafeCompilationOptions() by setting options.setInlineFunctions(Reach.NONE); instead of LOCAL.
Method interception doesn't work because Compiler.compile() is a Java class which is invoked by a Groovy class marked as #CompileStatic. That means Groovy's MOP is not used when process() calls Google's Compiler.compile(). Even ClosureCompilerProcessor.translateMinifyOptions() (Groovy code) can't be intercepted because the class is #CompileStatic. The only method that can be intercepted is ClosureCompilerProcessor.process().
Forking Google's closure-compiler.jar was my last ugly resort. But just like #Chad said below, simply inserting options.setInlineFunctions(Reach.NONE) in the right place didn't resurrect my inline JS functions names. I tried toggling other options such as setRemoveDeadCode=false to no avail. I realized what Chad said was right. I would end up flipping settings around and probably destroying how the minification works.
My solution: I pre-compressed ext-all-debug.js with UglifyJS and added them to my project. I could have named the files ext-all-debug.min.js to do it more cleanly but I didn't. Below are the settings I placed in my Grails Config.groovy:
grails.assets.minifyOptions = [
optimizationLevel: 'SIMPLE' // WHITESPACE_ONLY, SIMPLE or ADVANCED
]
grails.assets.minifyOptions.excludes = [
'**ext-all-debug.js',
'**ext-theme-neptune.js'
]
Done. Problem solved.
Keywords: minify, minification, uglify, UglifyJS, UglifyJS2

In this case, you would either need to make a custom build of the compiler or use the Java API.
However - disabling inlining is not enough to make this safe. Renaming and dead code elimination will also cause problems. This violates core assumptions of the compiler. This local function is ONLY referenced from within strings.
This code is only safe for the WHITESPACE_ONLY mode of the compiler.

Use the function constructor
var fnc = new Function("param1", "param2", "alert(param1+param2);");
Closure will leave the String literals alone.
See https://developer.mozilla.org/de/docs/Web/JavaScript/Reference/Global_Objects/Function

Browser.ExecScript() stopped working after updating windows

I've set up a simple testbed for WatiN (ver 2.1) which reads:
var browser = new IE();
browser.GoTo("http://www.google.co.il"); // webpage doesn't matter really
browser.RunScript("alert(123)");
This works only if KB3025390 is not installed. Installing it breaks the above test with an UnAuthorizedAccessException which has HRESULT set to E_ACCESSDENIED. What gives? Is there any workaround?
Update: Using IWebBrowser2.Navigate2 along with "javascript:console.log(123)" type of scripts works however
it makes me feel uneasy using such a backchannel
the scripts run through this back-channel of .Navigate2() may only have a max length of about 2070 chars (give or take) otherwise they get forcibly truncated to this length leading to javascript errors upon attempting to run them
using .Navigate2(), even with the most trivial script, will clog the ready state of Internet Explorer for good in the sense that it will be set to READYSTATE_LOADING without any hope of getting rid of it. In simple terms this means that once you use this hack, you either have to perform every single subsequent operation in WatiN in a "dont-wait-for-webpage-to-load" fashion (GoToNoWait, ClickNoWait etc) lest your code freezes upon waiting for the browser to turn back to READYSTATE_COMPLETE (which will never come about ofcourse as already mentioned).
there appears to be a much broader issue here in the sense that I can't even access the properties of an IHtmlWindow2 object p.e. window.document throws an unauthorized exception again making it virtually impossible to transfer over to the C# world the return-values of the scripts I'm running (using Expando etc) for documents other than window.top.document (for the window.top.document window there is IWebBrowser2.Document which does the trick)
Update#2: The folks over at the selenium project have also noticed this issue:
https://code.google.com/p/selenium/issues/detail?id=8302
A bug report has been created as well:
https://connect.microsoft.com/IE/feedback/details/1062093/installation-of-kb3025390-breaks-out-of-process-javascript-execution-in-ie11
Update#3: IHTMLWindow2.setInterval and IHTMLWindow2.setTimeout also throw UnauthorizedAccess exceptions. These methods are not marked as deprecated in:
http://msdn.microsoft.com/ko-kr/library/windows/desktop/aa741505%28v=vs.85%29.aspx
yet they have wounded up suffering from the same cutbacks all the same.
Update#4: I gave the approach recommended in this post a shot:
https://stackoverflow.com/a/18546866/863651
In order to dynamically invoke the "eval" method of the IHTMLWindow2 object (or any other method really). Got the same "System.UnauthorizedAccessException" as above. So no joy here either.
Microsoft recommends using "eval" over "execscript" however after the above experiment I suspect that they are refering to accessing "eval" only from within the browser.
As far as I can tell thus far, when it comes to the full-fledged IE11+ using "eval" out-of-process (via COM) appears to have been completely prohibited along with any other function-invocation of the window object, the only exception being the back-channel of the .Navigate2() mentioned above.

It turns out Microsoft eventually backpedaled on its decision to kill off .execScript at COM-level. Just install the latest updates for Windows including kb3025390: One of the updates for IE that came after kb3025390 brings back .execScript functionality at COM-level
Note, however, that .execScript is not accessible through IE's javascript anymore. In that context it's gone for good.

fyi: this one is also not working
ieInstance.Document.Script.<methodNameString>(<commaSeperatedParameterString>)
try this worked for me at some places but not all places
ieObject.Navigate "javascript:<methodNameString>(<commaSeperatedParameterString>)", Null, "_parent"
or
ieObject.Navigate2 "javascript:"<methodNameString>(<commaSeperatedParameterString>)", Null, "_parent"
now trying to find out solution using eval

I have found a way around the problem of an update installing automatically. You can just create a simple batch file with following content.
{code}
#echo off
wusa /uninstall /kb:3025390/quiet /norestart
END
{code}
Then go to task scheduler, create a new task for this batch file to run every one hour or day as per your requirements. Add it as a system task so it runs in the background and does not affect the running automations.

Declaring class differently for different Dojo versions without duplicating code?

I have an iWidget designed for IBM Connections, and my javascript code depends on Dojo (which is included by default in Connections).
It currently works in Connections 4.0 and 4.5, but is broken in Connections 5.0 (released last week), as Dojo has been updated to v1.9 and complains about my use of dojo.require.
These messages appear in the browser console when my widget tries to load on Connections 5.0:
Avoid calling dojo.require() to load classes at runtime, use net.jazz.ajax.xdloader.load_async() instead. Function '(anonymous)' required class 'dojox.atom.io.model'.
Avoid calling dojo.require() to load classes at runtime, use net.jazz.ajax.xdloader.load_async() instead. Function '(anonymous)' required class 'dojox.atom.io.Connection'.
I want to make conditional code that uses different ways of defining my widget class and requiring other Dojo modules depending on the Dojo version.
The widget javascript currently looks like this:
dojo.provide('insightCommunityWidgetClass');
dojo.require('dojox.atom.io.model');
dojo.require('dojox.atom.io.Connection');
dojo.declare('insightCommunityWidgetClass',null,{
// Class fields and methods. Currently 680 lines uncompressed.
});
I haven't yet created a version that works with Dojo 1.9 / Connections 5.0, but I think it would look something like this (and I'll have to make my javascript file name match the desired class name):
define(['dojo/_base/declare','dojox.atom.io.model','dojox.atom.io.Connection'], function(declare){
return declare(null, {
// Class fields and methods.
});
});
How can I have both of these in one file and choose between them without duplicating the class body?
Update:
I've attempted some conditional code, checking (define && define.amd) as suggested by Dimitri, tested this on Connections 4.0 and 4.5, and am getting very weird behaviour.
Temporarily ignoring any attempt to not duplicate my class, here's some conditional code which I've used exactly as shown, with a severely reduced widget class:
if (define && define.amd) {
console.log('Declaring insightWidgetClass with AMD (new method).');
define(['dojo/_base/declare','dojox/atom/io/model','dojox/atom/io/Connection'],
function(declare){
return declare(null,{
SVC_INV: 1,
onLoad: function() {
console.log('insightWidgetClass onLoad.');
}
});
}
);
} else {
console.log('Declaring insightWidgetClass with dojo.declare (old method).');
dojo.provide('insightWidgetClass');
dojo.require('dojox.atom.io.model');
dojo.require('dojox.atom.io.Connection');
dojo.declare('insightWidgetClass',null,{
SVC_INV: 1,
onLoad: function() {
console.log('insightWidgetClass onLoad.');
}
});
}
This seems not to run at all. None of my console.log messages appear in the browser console.
If I comment out the conditionals and make it so the only active code is the block after else, it runs. I get the "declaring ... (old method)" and the "insightWidgetClass onLoad" console messages.
I thought maybe enclosing the Dojo provide, require and declare calls in any kind of block might cause a problem, so I tested just putting the working code in an if (true) { block, and it still works.
The last things I've tried at this point are adding this one line before everything else, to see what define is:
console.log('dojo define',define);
... which breaks it. No console messages at all from my code.
Then I remove the define argument from that new line, so it's only sending a string to the console, and the code works again.
It seems like any mention of a define identifier silently stops the rest of the code from running.
There are no errors or warnings in the console indicating a problem. All I can say to that is: WTF?!
Now back to checking dojo.version instead.

Normally both should still work, dojo.provide() and dojo.require() are deprecated, but not entirely removed. Just make sure that your loading dojo in synchronous mode.
Besides that, the AMD way of coding is introduced in Dojo 1.7, which means that it should be supported on IBM Connections 4.5 as well (though I don't know about IBM Connections 4).
But if you really want to use both code bases, you can simply refer to the same object in stead of duplicating it, for example:
var myModule = {
// Class fields and methods.
};
if (dojo.version.major == 1 && dojo.version.minor == 9) {
define(['dojo/_base/declare','dojox.atom.io.model','dojox.atom.io.Connection'], function(declare){
return declare(null, myModule);
});
} else {
dojo.provide('insightCommunityWidgetClass');
dojo.require('dojox.atom.io.model');
dojo.require('dojox.atom.io.Connection');
dojo.declare('insightCommunityWidgetClass',null, myModule);
}
Or you could use the following check:
if (typeof define === 'function' && define.amd) {
// AMD style code
} else {
// Non-AMD style code
}
This is the approach most cross-loader libraries use. Libraries that work both on AMD loaders (Dojo, Require.js), but also on Node.js or simply by using global namespacing use a similar piece of code to determine how they load their module.

This is not your code, it should work as it is. We recently faced the same problem and identified the cause.
Connections 5 is using an AMD version of the Jazz framework which provides its own dojo loader. This framework is used to aggregate the needed dojo modules into a single JS file, which limits the number of requests to the server. Unfortunately, this loader no longer handles synchronous modules loading. It fails with the warning you reported when dojo.require() requests a module that is not yet loaded by the aggregator. If the module was already loaded, because it was part of the Jazz aggregated file, then it works. It explains why you can dojo.require() some modules, but not all of them.
-> A workaround is to deploy a server side OSGi bundle to get the modules you need part of the aggregated JS file. There is a documented extension point for this. This can unblock you while enhancing the performance of your page.
Now, we opened a PMR to IBM support. The development team is working on a resolution. We hope that they will be able to deliver a fix soon.
We reported the following issues:
dojo.require()
dojo.requireLocalization()
dojo.registerModulePath()/require({paths:})
If you think about something else, please let me know.

dart's latest js-interop library causes some issues lately

I have seen some strange changes in the latest js-interop library and I wonder if anybody can give some clarification about it.
After upgrading to the latest version I noticed dart2js doesn't work anymore. After some investigation I concluded the cause was an #proxy annotation inside the js-interop library ( also mentioned here).
Because of this I switched between a couple of versions and I noticed some functions like scoped have been deprecated in a timespan of only a couple of days after which it has been completely removed! If you missed the in between version in which this function is marked as deprecated you miss the hint which give's some info about it. Also note that the main tutorials about the js library on dartlang.org don't even give a hint about the fact that large parts of it have become outdated.
I decided to go back to version 0.0.26 and although it seemed to work as before... I noticed in one instance when retrieving a variable from the javascript context in dart I received a dart DateTime object and not a js.Proxy object.
Going back a version earlier (v0.0.25) I got back my js.Proxy when using a variable from the js context, as expected.
The weird thing is that on github the versions go until 0.0.25 (which work as expected) and the one on pub has 3 versions more, which all break backwards compatibility a lot (which sometimes is needed) without clear instructions about what is going on (which I find lightly frustrating).
Can somebody give some clarifications about what is going on and what I can expect for the coming times?
http://pub.dartlang.org/packages/js

All this breaking changes have been announced in Future breaking changes in package:js and BREAKING CHANGE: package:js deprecated features removed.
Basically, starting from 0.0.26, package:js is now baked with dart:js. This change comes with several things :
scopes/retain/release are no longer needed
several types are now transfered directly between Dart and Js and not proxied
null, bool, num, String, DateTime
Blob
KeyRange
ImageData
TypedData, including its subclasses like Int32List, but not ByteBuffer
Node
Element from shadow dom can now be transfered as well
Callback are now longer needed.
a really big performance improvement
Here's a quick migration guide :
scopes : remove js.retain, js.release and js.scoped.
replace new Callback.xxxx(f) with f and remove callback.dispose().
replace Proxy with transferable type based on the above list.