Just to make it clear to other readers:

You can add `/*jshint expr: true*/` to the top of the test files, so it only allows it in the test files.

In the rare case that you use that kind of expressions in your code, you can add the `expr: true` option to the jshint config options.

You can also use `myvalue.should.equal(true)` instead.

It turns our **jslint** is unable to solve my problem. And due to many restrictions of jslint, I turned to [jshint][1], and the option `expr` saved me :P

  [1]: http://www.jshint.com/

I want to active html5Mode in angularJS, but I don&#39;t know why it&#39;s not working. Is there anything wrong with my code?

&lt;!-- language: lang-js --&gt;

    angular
        .module(&#39;myApp&#39;,[])
        .config(function($locationProvider, $routeProvider) {
            $locationProvider.html5Mode(true);
            $routeProvider.when(&#39;/&#39;, {
               templateUrl: &#39;partials/home.html&#39;, 
               controller: HomeCtrl
            });
    
            $routeProvider.when(&#39;/tags/:tagId&#39;, {
                templateUrl: &#39;partials/result.html&#39;, 
                controller: TagResultCtrl
            });
            //$routeProvider.otherwise({redirectTo: &#39;/home&#39;, controller: HomeCtrl});
         });


in html

&lt;!-- language: lang-html --&gt;

      &lt;a href=&quot;tags/{{tag.id}}&quot;&gt;&lt;img data-ng-src=&quot;{{tag.imageUrl}}&quot;&gt;&lt;/a&gt;

How to config routeProvider and locationProvider in angularJS?

I see many similar questions but they&#39;re either so complex I can&#39;t understand them, or they don&#39;t seem to be asking the same thing.

It&#39;s simple: I have two columns: users (dmid) and downloads (dfid).

1. Select all users who downloaded a specific file:

        SELECT DISTINCT dmid FROM downloads_downloads where dfid = &quot;7024&quot;

2. Using the users above, find all the files they all downloaded:

        SELECT dfid from downloads_downloads WHERE dmid = {user ids from #1 above}

3. Count and order the dfid results , so we can see how many downloads each file received:

        dfid    dl_count_field
        ----    --------------
        18       103
        3        77
        903      66

 
**My attempt at answering.**

This seems close, but MySql bogs down and doesn&#39;t respond even after 30 seconds--I restart Apache eventually. And I do not now how to structure the count and order by without getting syntax errors because of the complex statement--and it may not even be the right statement.

    SELECT dfid from downloads_downloads WHERE dmid IN (
        SELECT DISTINCT dmid FROM `downloads_downloads` where dfid = &quot;7024&quot;)


Use results from one sql query in another where statement (subquery?)

I am writing JS UT for my NodeJS code. I am using [Chai][1] as the assertion library, and I prefer the *should* syntax. I also use *jslint* to check the JS file syntax, even the JS files for UT.

Now I have a problem with *jslint* and *Chai*. In *Chai*, you can use:

    myvalue.should.be.true;

But *jslint* give me:

    #1 Expected an assignment or function call and instead saw an expression.

I know *jslint* comes with many options, but I just cannot find the right one to turn off this check.

  [1]: http://chaijs.com/

How to get &quot;should.be.false&quot; syntax pass jslint?

I am writing JS UT for my NodeJS code. I am using <a href="http://chaijs.com/" target="_blank" rel="noopener noreferrer">Chai</a> as the assertion library, and I prefer the should syntax. I also use jslint to check the JS file syntax, even the JS files for UT.
Now I have a problem with jslint and Chai. In Chai, you can use:
<pre><code class="hljs language-arduino">myvalue.should.be.true;
</code></pre>
But jslint give me:
<pre><code class="hljs language-bash">#1 Expected an assignment or function call and instead saw an expression.
</code></pre>
I know jslint comes with many options, but I just cannot find the right one to turn off this check.

I&#39;ve worked with `Node.js` for a little while and consider myself pretty good with Java.  But I just discovered `Akka` and was immediately interested in its actor pattern (from what I understand).

Now, assuming my JavaScript skills were on par with my Scala/Java skills, I want to focus on the practicality of either system.  Especially in the terms of web services.

It was my understanding that Node is excellent at handling many concurrent operations.  I imagine a good Node web service for an asset management system would excel at handling many users submitting changes at the same time (in a large, heavy traffic application).

But after reading about the actors in Akka, it seams it would excel at the same thing.  And I like the idea of reducing work to bite-sized pieces.  Plus, years ago I dabbled in Erlang and fell in love with the message passing system it uses.

I work on many applications that deal with complex business logic and I&#39;m thinking it&#39;s time to jump heavier into one or the other.  Especially upgrading legacy Struts and C# applications.

Anyway, avoiding holy wars, how are the two systems fundamentally different?  It seems both are geared towards the same goal.  With maybe Akka&#39;s &quot;self-healing&quot; architecture having an advantage.

**EDIT**

It looks like I am getting close votes.  Please don&#39;t take this question as a &quot;which is better, node or akka?&quot;.  What I am looking for is the fundamental differences in event driven libraries like Node and actor based ones like Akka.

How is Node.js evented system different than the actor pattern of Akka?

I am using MongoDB with Node.JS. I have a collection which contains a date and other rows. The date is a JavaScript `Date` object.

How can I sort this collection by date?


How to sort a collection by date in MongoDB?

I am doing MongoDB lookups by converting a string to BSON. Is there a way for me to determine if the string I have is a valid ObjectID for Mongo before doing the conversion?

Here is the coffeescript for my current findByID function. It works great, but I&#39;d like to lookup by a different attribute if I determine the string is not an ID.

    db.collection &quot;pages&quot;, (err, collection) -&gt;
      collection.findOne
        _id: new BSON.ObjectID(id)
      , (err, item) -&gt;
        if item
          res.send item
        else
          res.send 404

Can I determine if a string is a MongoDB ObjectID?

Hi this is my method in a node js file:

    exports.start = function() {
    	console.log(&#39; in start of sender.js&#39;);
    });

How can I call this method in the same js file? I tried calling start() and exports.start() but not successful.


calling exports.start in same js file node.js

I understand that doing something like

    var a = &quot;hello&quot;;
    a += &quot; world&quot;;
It is relatively very slow, as the browser does that in `O(n)` . Is there a faster way of doing so without installing new libraries? 

Fast way to concatenate strings in nodeJS/JavaScript

I have been validating my JavaScript using JSLint for about 2 years now and once in a while there are rules that change. In general when JSLint introduces a new rule, there is a checkbox to ignore this rule when parsing, or if you choose to not ignore it then to make your code compliant to it.

As I was running my JSLint validation today, however, I run into these two new errors:

&gt; Use spaces, not tabs.

This is not the &quot;mixing of tabs and spaces&quot; error. I am using only tabs. This is a recently modified version of &quot;mixing of tabs and spaces&quot; which now disallows tabs in general.


And:

&gt; Unsafe character. 
&gt;
&gt; */
&gt; 
&gt; Unsafe character.     
&gt; 
&gt; _const: {


There are no new options to ignore. I cannot understand what is unsafe about closing a block comment, why it considers _const: { as unsafe when I have `nomen: true`, (dangling _ in identifiers) or why should I be suddenly switching from spaces to tabs, when I still have the configuration about indentation of 4 spaces being a tab. 

Does anyone have an idea why those were introduced to at least how to make JSLint ignore these new rules?

**Update:**
The *`Messy White Space`* option works around the issue but it would cause other unexpected behavior:

    if (condition) { 
      //            ^-- there is a space but it won&#39;t indicate an error

Why were the new JSLint errors &quot;use spaces, not tabs&quot; and &quot;unsafe character&quot; introduced?

I was just linting some JavaScript code using JSHint. In the code I have two for-loops both used like this: 

    for (var i = 0; i &lt; somevalue; i++) { ... }

So both for-loops use the var i for iteration.

Now JSHint shows me an error for the second for-loop: &quot;&#39;i&#39; is already defined&quot;. I can&#39;t say that this isn&#39;t true (because it obviously is) but I always thought this wouldn&#39;t matter as the var i is only used in that specific place. 

Is it bad practice to use for-loops this way? Should I use a different variable for each for-loop in my code like

    //for-loop 1
    for (var i = 0; ...; i++) { ... }
    
    //for-loop 2
    for (var j = 0; ...; j++) { ... }

Or is this on e of the errors I can ignore (because it doesn&#39;t break my code, it still does what it is supposed to do)?

JSLint btw. stops validating at the first for loop because I don&#39;t define var i at the top of the function (that&#39;s why I switched to JSHint in the first place). So according to the example in this question: https://stackoverflow.com/questions/6803305/should-i-use-jslint-or-jshint-javascript-validation/10763615#10763615 – I should use for-loops like this anyway to confirm JSLint: 

    ...
    var i;
    ...
    //for-loop 1
    for (i = 0; ...; i++) { ... }
    ...
    //for-loop 2
    for (i = 0; ...; i++) { ... }

This also looks good to me, because this way I should avoid both errors in JSLint and JSHint. But what I am uncertain about is if I should use a different variable for each for-loop like this: 

    ...
    var i, j;
    ...
    //for-loop 1
    for (i = 0; ...; i++) { ... }
    //for-loop 2
    for (j = 0; ...; j++) { ... }

So is there a best practice for this or could I just go with any of the codes above, meaning I choose &quot;my&quot; best practice?

Is it bad practice to use the same variable name in multiple for-loops?

In my project we have some global variables that work as containers:

    MyProject.MyFreature.someFunction = function() { ... }

So then I use that script across the site and JSLint / JSHint complains about that:

&gt; &#39;MyProject&#39; is not defined

I know that I can go to every JavaScript file and add the comment `/*global MyProject*/` on top of it. But I&#39;m looking a way to define that comment in some sort of config file so I don&#39;t have to go file by file adding this comment.

Some kind on option in the `config/jshint.yml` would be nice.

How to tell JSLint / JSHint what global variables are already defined

This is the error I get when using const:

    &lt;error line=&quot;2&quot; column=&quot;1&quot; severity=&quot;warning&quot; message=&quot;&amp;apos;const&amp;apos; is available in ES6 (use esnext option) or Mozilla JS extensions (use moz).&quot; source=&quot;jshint.W104&quot; /&gt;


My code looks like this:

    const Suites = {
        Spade: 1,
        Heart: 2,
        Diamond: 3,
        Club: 4
    };

The code works fine only JSHint is warning me every time.

Why does JSHint throw a warning if I am using const?

From time to time, I get TSLint errors &quot;block is empty&quot;. This happens e.g. when I pass a no-op callback to a function:

    doSomething(() =&gt; {});

From what I read, JSLint apparently does the same, but I didn&#39;t verify that.

I find these usages completely valid, so I tried to find a reason why empty blocks are considered bad at all. But the only thing I&#39;m able to find (e.g. in [this answer](https://stackoverflow.com/a/17685875/219187)) are instructions to add a `return;` to avoid the error. This is **not** what I want to do in every empty callback.

Why does TSLint report above empty block as problem? Is there any reason why I shouldn&#39;t disable the check?

Why do TSLint and JSLint report empty blocks?

I am using node, mocha, and chai for my application. I want to test that my returned results data property is the same &quot;type of object&quot; as one of my model objects (Very similar to chai&#39;s instance). I just want to confirm that the two objects have the same sets of property names. **I am specifically not interested in the actual values of the properties.**

Let&#39;s say I have the model Person like below.  I want to check that my results.data has all the same properties as the expected model does.  So in this case, Person which has a firstName and lastName.

So if `results.data.lastName` and `results.data.firstName` both exist, then it should return true.  If either one doesn&#39;t exist, it should return false.  A bonus would be if results.data has any additional properties like results.data.surname, then it would return false because surname doesn&#39;t exist in Person.

**This model**


    function Person(data) {
      var self = this;
      self.firstName = &quot;unknown&quot;;
      self.lastName = &quot;unknown&quot;;
    
      if (typeof data != &quot;undefined&quot;) {
         self.firstName = data.firstName;
         self.lastName = data.lastName;
      }
    }




How can I check that two objects have the same set of property names?

I&#39;m hoping to find some help with this problem.  I&#39;m trying to write tests for an application I am writing.  I have distilled the problem in to the following sample code.  I want to test that an error was thrown.  I&#39;m using Testacular as a test runner with mocha as the framework and chai as the assertion library.  The tests run, but the test fails because an error was thrown! Any help is greatly appreciated!


    function iThrowError() {
    	throw new Error(&quot;Error thrown&quot;);
    }

    var assert = chai.assert,
        expect = chai.expect;
    describe(&#39;The app&#39;, function() {
    	describe(&#39;this feature&#39;, function() {
    		it(&quot;is a function&quot;, function(){
    			assert.throw(iThrowError(), Error, &quot;Error thrown&quot;);
    		});
    	});
    });

Testing for errors thrown in Mocha

In my node application I&#39;m using mocha to test my code. While calling many asynchronous functions using mocha, I&#39;m getting timeout error (`Error: timeout of 2000ms exceeded.`). How can I resolve this?
  

    var module = require(&#39;../lib/myModule&#39;);
    var should = require(&#39;chai&#39;).should();
    
    describe(&#39;Testing Module&#39;, function() {
    
        it(&#39;Save Data&#39;, function(done) {
    
            this.timeout(15000);
    
            var data = {
                a: &#39;aa&#39;,
                b: &#39;bb&#39;
            };
    
            module.save(data, function(err, res) {
                should.not.exist(err);
                done();
            });
    
        });
    
    
        it(&#39;Get Data By Id&#39;, function(done) {
    
            var id = &quot;28ca9&quot;;
    
            module.get(id, function(err, res) {
    
                console.log(res);
                should.not.exist(err);
                done();
            });
    
        });
    
    });

In mocha testing while calling asynchronous function how to avoid the timeout Error: timeout of 2000ms exceeded

Why does the following fail?

    expect([0,0]).to.equal([0,0]);

and what is the right way to test that?

chai test array equality doesn&#39;t work as expected

Building on [this][1] tutorial testing an angularjs app with chai, I want to add a test for an undefined value using the &quot;should&quot; style. This fails:

    it (&#39;cannot play outside the board&#39;, function() {
      scope.play(10).should.be.undefined;
    });

with error &quot;TypeError: Cannot read property &#39;should&#39; of undefined&quot;, but the test passes with the &quot;expect&quot; style:

    it (&#39;cannot play outside the board&#39;, function() {
      chai.expect(scope.play(10)).to.be.undefined;
    });

How can I get it working with &quot;should&quot;?

  [1]: http://www.alexrothenberg.com/2013/08/06/how-to-unit-test-an-angular-app.html

Content Type	Original Author	Original Content on Stackoverflow
Question	David S.	View Question on Stackoverflow
Solution 1 - node.js	Jesús Carrera	View Answer on Stackoverflow
Solution 2 - node.js	Beau	View Answer on Stackoverflow
Solution 3 - node.js	David S.	View Answer on Stackoverflow

How to get "should.be.false" syntax pass jslint?

node.js Problem Overview

node.js Solutions

Solution 1 - node.js

Solution 2 - node.js

Solution 3 - node.js

Use results from one sql query in another where statement (subquery?)

How to config routeProvider and locationProvider in angularJS?

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