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

Question

In my node application I m using mocha to test my code  While calling many asynchronous functions using mocha  I m getting timeout error  Error  timeout of 2000ms exceeded    How can I resolve this   var module   require     lib myModule    var should   require  chai   should     describe  Testing Module   function          it  Save Data   function done             this timeout 15000            var data                 a   aa               b   bb                      module save data  function err  res                should not exist err               done                               it  Get Data By Id   function done             var id    28ca9            module get id  function err  res                 console log res               should not exist err               done

User · Answer

If you are using arrow functions   it  should do something   async      gt         do your testing    timeout 15000

User · Answer

My issue was not sending the response back  so it was hanging  If you are using express make sure that res send data   res json data  or whatever the api method you wanna use is executed for the route you are testing

User · Answer

For me the problem was actually the describe function  which when provided an arrow function  causes mocha to miss the  timeout  and behave not consistently   Using ES6   since no promise was rejected I was getting this error all the time for different tests that were failing inside the describe block  so this how it looks when not working properly   describe  test        gt      assert           and this works using the anonymous function  describe  test   function       assert           Hope it helps someone  my configuration for the above   nodejs  8 4 0  npm  5 3 0  mocha  3 3 0

User · Answer

A little late but someone can use this in future   You can increase your test timeout by updating scripts in your package json with the following    scripts           test    test --timeout 10000    Adjust to a value you need      Run your tests using the command test

User · Answer

I find that the  solution  of just increasing the timeouts obscures what s really going on here  which is either   Your code and or network calls are way too slow  should be sub 100 ms for a good user experience  The assertions  tests  are failing and something is swallowing the errors before Mocha is able to act on them    You usually encounter  2 when Mocha doesn t receive assertion errors from a callback  This is caused by some other code swallowing the exception further up the stack  The right way of dealing with this is to fix the code and not swallow the error   When external code swallows your errors  In case it s a library function that you are unable to modify  you need to catch the assertion error and pass it onto Mocha yourself  You do this by wrapping your assertion callback in a try catch block and pass any exceptions to the done handler   it  should not fail   function  done       Pass reference here     i swallow errors function  err  result        try      boilerplate to be able to get the assert failures       assert ok true         assert equal result   bar          done          catch  error          done error                     This boilerplate can of course be extracted into some utility function to make the test a little more pleasing to the eye   it  should not fail   function  done       Pass reference here      i swallow errors handleError done  function  err  result            assert equal result   bar                     reusable boilerplate to be able to get the assert failures function handleError done  fn        try            fn            done          catch  error            done error             Speeding up network tests  Other than that I suggest you pick up the advice on starting to use test stubs for network calls to make tests pass without having to rely on a functioning network  Using Mocha  Chai and Sinon the tests might look something like this  describe  api tests normally involving network calls   function          beforeEach  function              this xhr   sinon useFakeXMLHttpRequest            var requests   this requests                this xhr onCreate   function  xhr                requests push xhr                          afterEach  function              this xhr restore                it  should fetch comments from server   function              var callback   sinon spy            myLib getCommentsFor   some article   callback           assertEquals 1  this requests length            this requests 0  respond 200     Content-Type    application json                                           id   12   comment    Hey there                expect callback calledWith    id  12  comment   Hey there       to be true                 See Sinon s nise docs for more info

User · Answer

Make sure to resolve reject the promises used in the test cases  be it spies or stubs make sure they resolve reject

User · Answer

You can either set the timeout when running your test   mocha --timeout 15000   Or you can set the timeout for each suite or each test programmatically   describe        function      this timeout 15000      it        function done       this timeout 15000       setTimeout done  15000               For more info see the docs

[node.js] In mocha testing while calling asynchronous function how to avoid the timeout Error: timeout of 2000ms exceeded

Examples related to node.js

Examples related to mocha.js

Examples related to chai