Unit Testing for Exceptions

Classic Servoy
1

In order for unit tests to really provide full coverage you need to make sure you are testing that your function throws exceptions when it’s supposed to (lack of arguments, bad arguments, etc).

Currently we’re rolled our own solution for this with the following function

function assertException(fMethod, aArg, sMessage)
{
	var bCaught = false;
	try
	{
		fMethod.apply(null, aArg);
	}
	catch (e)
	{
		bCaught = true;
	}
	
	if (!bCaught)
	{
		jsunit.fail(sMessage);
	}
}

But would be nice if our jsunit natively provided this kind of functionality. In other unit testing packages I’ve seen things like assertFail or assertThrows.

Official Request: https://support.servoy.com/browse/SVY-2596

2

Hi,

Did you see the help for the JSUnit node in the Solution Explorer? Unless you mean something else what you ask for is already there?

//Fails a test. AssertionFailedError is always thrown.
jsunit.fail("Fail test");
3

Yes, I’ve checked that out…it’s actually what I use to make my work-around method above :-)

jsunit.fail() is a way to force a unit test failure
what I’m looking for is a way to test for the successful throwing of an exception.
For instance:

function add(a, b) {
	if (a == null | b == null) {
		throw "ArgumentException";
	}
	return a + b;
}

function test_add(){
	//Unit test should pass because "ArgumentException" was thrown
	jsunit.assertException(add(null, null)); 
}
4

things like that is normally done like:

function test_add() { 

   try {
     add(1,2);
     jsunit.fail();
   } catch (e) {
    // should come in here
   }
}