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Javascript Dot-Syntax function disappears in listen callback

I'm trying to update Annotorious (https://annotorious.github.io/#) to the latest version of Closure / Javascript.
When I compile it with "SIMPLE" optimizations, dot-syntax functions seem to disappear when goog.events.listen callbacks are invoked. Here's an example:
Here's the "main":
goog.provide('annotorious.Annotorious');
...
/**
* The main entrypoint to the application. The Annotorious class is instantiated exactly once,
* and added to the global window object as 'window.anno'. It exposes the external JavaScript API
* and internally manages the 'modules'. (Each module is responsible for one particular media
* type - image, OpenLayers, etc.)
* #constructor
*/
annotorious.Annotorious = function() {
/** #private **/
this._isInitialized = false;
/** #private **/
this._modules = [ new annotorious.mediatypes.image.ImageModule() ];
...
In another file (they're all compiled together), we have this:
goog.provide('annotorious.Annotation');
goog.require('annotorious.shape');
/**
* A 'domain class' implementation of the external annotation interface.
* #param {string} src the source URL of the annotated object
* #param {string} text the annotation text
* #param {annotorious.shape.Shape} shape the annotated fragment shape
* #constructor
*/
annotorious.Annotation = function(src, text, shape) {
this.src = src;
this.text = text;
this.shapes = [ shape ];
this['context'] = document.URL; // Prevents dead code removal
}
So we start up the code, and at some point we end in the editor for the annotation, listening for a "Save" button:
goog.provide('annotorious.Editor');
....
/**
* Annotation edit form.
* #param {Object} annotator reference to the annotator
* #constructor
*/
annotorious.Editor = function(annotator) {
this.element = goog.soy.renderAsElement(annotorious.templates.editform);
....
/** #private **/
//this._btnSave = goog.dom.query('.annotorious-editor-button-save', this.element)[0];
this._btnSave = this.element.querySelector('.annotorious-editor-button-save');
...
goog.events.listen(this._btnSave, goog.events.EventType.CLICK, function(event) {
event.preventDefault();
var annotation = self.getAnnotation();
annotator.addAnnotation(annotation);
annotator.stopSelection();
if (self._original_annotation)
annotator.fireEvent(annotorious.events.EventType.ANNOTATION_UPDATED, annotation, annotator.getItem());
else
annotator.fireEvent(annotorious.events.EventType.ANNOTATION_CREATED, annotation, annotator.getItem());
self.close();
});
If I put a breakpoint at "goog.events.listen(this._btnSave...", and type "annotorious.Annotation", I get what I expect:
In fact, it has all kinds of methods:
Then I let the code go, and break in the listener (event.preventDefault();, etc, above):
Now, all the dot-syntax methods are gone.
This of course causes crashes later on.
All of these files are compiled together.
This happens for all callbacks - 'load' events, other ux callbacks, etc.
This must have worked in prior versions of Closure / JS.
What could be causing this?
Thanks!

Ok, I was able to resolve the problem by adding "--assume_function_wrapper" to the closure compiler command line.
Previously, I was compiling the package using Plovr. However, since Plovr hasn't been updated in a long time, I switched to using the closure compiler natively.
Apparently either Plovr provided '--assume_function_wrapper' internally or the version of the compiler Plovr used didn't break the functions as described.
As #john suggests above I'll bet '--assume_function_wrapper' keeps goog.provide from "destroying" namespaces by re-declaring them.

How do I document NodeJS native (V8) modules?

I have developed a native NodeJS module (using the NAN helpers). Now I am wondering what is the best way to document it.
The methods the module exports exist only in the C++ source code, however I wish to export Javascript documentation.

EDIT: I found another way that I think is better:
All JSDoc needs is to be able to attach the doclet to SOMETHING, so you can actually just do this (if you ignore JSHint warning about expecting an assignment or call instead of expression):
var nativeStuff = require('some/native/stuff');
/**
* My Cool Class
* #class
*/
nativeStuff.MyCoolClass;
/**
* My Cool Method
* #function
* #param {String} [name] The argument
*/
nativeStuff.MyCoolClass.prototype.CoolMethod;
/**
* Some Other Value
* #type {String}
*/
nativeStuff.someStringValue;
module.exports = nativeStuff;
This has the advantage of working with IDE's (at least WebStorm) and not requiring you to copy or proxy the object itself. Note though that you have to explicitly tell it what kind of field each entry is (with #function or #class or #type) because it can't infer it automatically otherwise.
Original Answer
There are a couple ways I know of, though I admit none seem particularly elegant.
In the small adapter file where you require() the native parts of the code and make it available as a module, you can assign each component individually and document them that way:
var nativeStuff = require('some/native/stuff');
// If your module only has one thing
/**
* My Cool Class
* #class MyCoolClass
*/
module.exports = nativeStuff;
// If it has several things
module.exports = {
/**
* My cool class
* #class
*/
MyCoolClass: nativeStuff.MyCoolClass,
/**
* My Other Cool Member
*/
OtherCoolMember: nativeStuff.OtherCoolMember
};
You could document members of the class this way too if you want to pick apart the class and re-assemble it, but it gets kinda unwieldy the deeper you go.
The other way I know of is to wrap every class method in native JS, which comes with a (almost negligible) performance hit:
var nativeStuff = require('some/native/stuff');
/**
* My Cool Class
*/
class MyCoolClass {
constructor() {
this._nativeObj = new nativeStuff.MyCoolClass();
}
/**
* Some Cool Method
* #param {String} [name] My name
*/
coolMethod(name) {
return this._nativeObj(name);
}
}
module.exports = MyCoolClass;
(Note this also works in older JS versions, but ES6 classes make stuff way easier to understand visually :)
You also can try using the #typedef directive to define things since a doclet about a typedef can be separate from the object it describes, but I don't think typedef's can document methods or classes in general, they're just for data objects.

I had to create a simple documentation generator to scan comments in source code in Javadoc-like style: https://github.com/aspectron/gendoc
Here is a part of such documentation, that looks like this:
/**
#module crypto
**/
/**
#class Hash
Hash generator
#function Hash(algorithm)
#param algorithm {String}
Constructor. Initiaize hash generator with specified algorithm, see #getHashes
Throws exception on unknown algorithm
**/
v8pp::class_<hash_generator> hash_class(bindings.isolate(), v8pp::v8_args_ctor);
hash_class
/**
#function reset([algorithm])
#param [algorithm] {String}
#return {Hash}
Reset hash generator to initial state optionaly changing generator algorithm.
Throws exception on unknown algorithm.
**/
.set("reset", &hash_generator::reset_v8)
...

Finally I opted for a not very elegant solution. I have created a separate JavaScript file which only has methods that are exported by my native API.
This file looks like this:
/** #namespace AwesomeLibrary
*
* #description API overview
*/
AwesomeLibrary = {
/**
* #param {string} param Input parameter
* #return combobulates {#link param}
*/
combobulate: function (param) {}
}
Then I am using JsDoc to generate the documentation of the project and passing this JavaScript file as an input rather than my native code. Finally I bundle the documentation with the binary distribution of my module.
This solution is not ideal as the documentation and the source code have to be maintained separately, however it has the advantage of zero overhead and a (rather) clean file. I have also disabled the source code generation in JsDoc as this would be obviously quite useless and only show the empty stubs.

Prevent Closure Compiler from renaming properties without using bracket notation

I'm working on a product which needs to conditionally expose an API to the end user. We're using the Closure Compiler for minification. The part of the API that I'm trying to expose is a function that calls a callback with a Result whose value is an object with certain properties.
Specifically, the function I'm trying to expose looks like this (in pseudo-jsdoc notation):
/**
* #type DocumentRenderResult {status: String, image?: HTMLImageElement|HTMLCanvasElement}
* #param {function(Result<DocumentRenderResult>)} callback
**/
function renderDocument (url, page, callback) {
}
And the Result class looks like this:
/**
* #template T
* #param {Boolean} ok
* #param {T} val
* #param {Error} err
**/
function Result (ok, val, err) {
this.ok = ok;
this.val = val;
this.err = err;
}
What I'd like is to expose both the Result object API - that is, the fact that there are ok, val, and err properties, and expose the renderDocument interface so that users providing a callback will be able to access the status and image properties.
One solution (possibly) is to use bracket notation everywhere, but since this is supposed to be only conditionally exposed (for certain end users), I'd like to separate the concept of whether it's minified or not from the code.
I think some combination of #implements and #export and an externs file can accomplish this, but I haven't figured it out.
Is what I'm trying to do possible?

There are 2 primary ways to handle this situation:
Without Closure-Library
Store all of your exports in a separate file that becomes the main entry point for the api exposed library. This methodology has no dependencies on external libraries. For an example of this, see my GeolocationMarker library.
With Closure-Library (or at least a part of it)
If you are willing to utilize a very small part of closure-library code in your project, you can use the #export annotation. #export annotations do nothing unless the compilation flag --generate_exports is specified.
When --generate_exports is used, the compiler will add the appropriate call to either closure-library's goog.exportProperty or goog.exportSymbol method.
/** #const */
var mynamespace = {};
/** #export */
mynamespace.maybeExposedMethod = function() {};
With the --generate_exports flag, the compiler will generate the code:
var mynamespace = {maybeExposedMethod:function() {}};
goog.exportSymbol("mynamespace.maybeExposedMethod",
mynamespace.maybeExposedMethod);
Instead of having to depend on all of closure-library. You can copy the definition for those 2 methods into your source. All that's needed is that they exist as those names.
Conditionally Renaming Record Types
Functions which return anonymous objects must be treated differently to prevent renaming. The best option here would be to define a record type in its own file. For the public api to block renaming, include the record definition as an extern. When you want the record properties to be renamed, include the definition as source.
my_typedefs.js
/** #typedef {{image: string, status: number}} */
var my_record_type;
my_method_def.js
/** #return {my_record_type} */
function my_method() {
return {
image: 'some_image.jpg',
status: 200
};
}
If my_typedefs.js is included in the compilation with the --js flag, the record properties will be renamed, but if it is included with the --externs flag, they will not be renamed.

typedef of this variable doesn't produce warning

I want to produce a warning for a number if a string is assigned to it. So, I thought typedef of Closure might do this for me. I tried the following -
var Widget = function()
{
/** #typedef {number} */
this.size = null;
};
new Widget().size = "kaboom!"
When I compile it using http://closure-compiler.appspot.com/home it doesn't throw a warning or error. What am I doing wrong? And/or what other tool should I be using?

Turn the optimization up to Advanced in the closure compiler service to catch these warnings. You still won't see any for your example (well, you will see some, but not what you are expecting), because typedefs are used to define custom types. Also, you need to annotate your constructor. Run the following example in advanced mode and you will see your warnings. Instead of making a typedef for a simple thing like number, I would just use #type, but this example is to show you the proper use of typedef.
/** #typedef {number} */
var customType;
/** #constructor */
var Widget = function()
{
/** #type {customType} */
this.size = null;
};
new Widget().size = "kaboom!"

requirejs exports doesn't work in firefox 15

I use a external library that uses requirejs I don't know
how its work but FileError is in the global scope in other browser
or in FF8 but in FF 14/15 says FileError not defined.
define(function (require, exports, module) {
"use strict";
var Async = require("utils/Async");
var NativeFileSystem = {
/**
* LOT OF CODE HERE
* ...
* ...
* ...
*/
/** class: FileError
*
* Implementation of HTML file API error code return class. Note that we don't
* actually define the error codes here--we rely on the browser's built-in FileError
* class's constants. In other words, external clients of this API should always
* use FileError.<constant-name>, not NativeFileSystem.FileError.<constant-name>.
*
* #constructor
* #param {number} code The error code to return with this FileError. Must be
* one of the codes defined in the FileError class.
*/
NativeFileSystem.FileError = function (code) {
this.code = code || 0;
};
/**
*THIS FIX THE PROBLEM BUT IT A HACK
*window.FileError = NativeFileSystem.FileError;
*/
// Define public API
exports.NativeFileSystem = NativeFileSystem;
});
Of course if I add window.FileError = NativeFileSystem.FileError; after the
function definition its work fine. But I don't want hack the library
The full source of the file is here

Brackets relies on the FileError class only for the error code constants.
The FileAPI is still a draft spec http://www.w3.org/TR/FileAPI/ and it appears they have changed FileError to DOMError in the time since we originally wrote NativeFileSystem. We could remove this dependency and define our own equivalent FileError constants to remove the dependency. We were attempting to model our API after the FileAPI, but it's been a moving target.