Question

It seems that most XUnit testing frameworks provide assertions for the times when you want to assert that a given operation will thrown an exception (or an Error in AS3 parlance.) Is there some ‘standard’ way of doing this that I am overlooking, which would explain the absence of an assertError() assertion included with FlexUnit?

I know HOW to implement such a thing, and I will probably add it to my FlexUnit (go open source!), but it seems like such a glaring omission that I’m left wondering if I’m just doing it wrong.

Anyone have thoughts on this?

Answer 1

Edit 05/02/2010: I’d now recommend using FlexUnit 4. It uses an extensible metdata system, supports expected exceptions, and also supports running in an integration server environment without the use of AIR.

Edit: You should have a look at fluint, which was built by people who had enough of FlexUnit and it’s limitations. It might have some of these types of assertions built in.

I totally agree. In fact, FlexUnit is missing several useful methods (assertEvent, assertArrayEquals, etc). I know you said you know how to implement it, but feel free to use mine:

public static function assertError(message : String, func : Function, errorClass : Class = null, errorMessage : String = null, errorCodes : Array = null) : Error  {     _assertionsMade++;      if (errorClass == null) errorClass = Error;      try     {         func();     }     catch(ex : Error)     {         if (!(ex is errorClass))         {             fail('Expected error of type '' + getQualifiedClassName(errorClass) + '' but was '' + getQualifiedClassName(ex) + ''');         }          if (errorMessage != null && ex.message != errorMessage)         {             fail('Expected error with message '' + errorMessage + '' but was '' + ex.message + ''');         }          if (errorCodes != null && errorCodes.indexOf(ex.errorID) == -1)         {             fail('Expected error with errorID '' + errorCodes.join(' or ') + '' but was '' + ex.errorID + ''');         }          return ex;     }      if (message == null)     {         message = 'Expected error of type '' + getQualifiedClassName(errorClass) + '' but none was thrown'     }      fail(message);      return null; }