Project Description
A .NET port of Groovy's Power Assert, which prints out a decomposition of your expression tree (with values) whenever an assertion fails

An excellent description of groovy's PowerAssert can be found at http://dontmindthelanguage.wordpress.com/2009/12/11/groovy-1-7-power-assert/

What does Power Assert .NET do?

Given the following unit test:

[Test]
public void RunComplexExpression()
{
   int x = 11;
   int y = 6;
   DateTime d = new DateTime(2010, 3, 1);
   PAssert.IsTrue(() => x + 5 == d.Month * y);
}

Power Assert will cause a failure with the following message:

System.Exception : IsTrue failed, expression was:

x + 5 == d.Month * y
| |   |  | |     | |
| |   |  | |     | 6
| |   |  | |     18
| |   |  | 3
| |   |  01/03/2010 00:00:00
| |   False
| 16
11

Equals vs ==

Given the following unit test:

[Test]
public void EqualsButNotOperatorEquals()
{
    var t1 = new Tuple<string>("foo");
    var t2 = new Tuple<string>("foo");

    PAssert.IsTrue(() => t1 == t2);
}

Power Assert will cause a failure with the following message:

System.Exception : IsTrue failed, expression was:

t1 == t2
|  |  |
|  |  (foo)
|  False, but would have been True if you'd called .Equals()
(foo)


Pull requests and feature requests are welcomed!

Last edited Nov 14, 2010 at 12:19 PM by robfe, version 5