Introduction to Unit Testing
Unit testing – testing methods/classes
of the program
• Test suite is composed of several tests
• Test suite should cover all the statements
• Tests calls Assert functions
What is the Assert Class
• One Assert per test
– Short circuit
– Write simple and concise tests
• Checks if different conditions are true
Assert Functions
• Assert::IsFalse(…) - 3 Basic Overloads
-Assert::IsFalse( bool condition);
-Assert::IsFalse( bool condition, string message );
-Assert::IsFalse( bool condition, string message,
object[] parms );
• One Assert per test
– Short circuit
– Simple and concise tests
Assert Functions
 AreEqual(int actual, int expected)
 AreEqual(double actual, double expected)
 AreEqual(float actual, float expected)
 AreEqual(decimal actual, decimal expected)
 AreEqual(object actual, object expected)
 AreSame (object actual, object expected)
Assert Functions
 IsTrue( bool condition)
 IsFalse( bool condition)
 IsNull( object obj)
 IsNotNull( object obj)
 Fail()
 Ignore()
Tools available
•
•
•
•
NUnit
WinUnit
Visual Studio 2005 Team Edition
Visual Studio 2008 Professional Edition
Exercise – Use Unit testing in Visual
Studio 2008
Create a new test project
• Create a new solution and project
• Add name
• Click OK
Add subject class
• Download from blackboard the files:
– Grade.cpp
– Grade.h
• Save and add the files in your project
• Some configuration properties need to be
changed
– See next 2 slides
Configuring…Project->Properties
(Alt+F7)
Configuring – more…
Configuring…Done!
• Build the project
• Run the test cases
– Test->Run->All Tests in Solution
Writing tests
• Write a test for setScore(double) method
void setScore(double newscore){
if ((0<=newscore)&&(newscore<=100)){
score = newscore;
}
}
• What if newscore = 100
[TestMethod]
void TestMethod1()
{
Grade *g = new Grade();
g->setScore(100);
Assert::AreEqual(100.0, g->getScore());
};
• What if newscore = -1
• What if newscore = 101
Exercises
• Complete the exercises from the file: Unit
Testing Tutorial.doc
Warning
• Sometimes configuring larger projects to
include testing is not trivial
– Testing in Notepad++ and WinMerge - not yet 
• Other unit testing tools are easier to configure
– JUnit – testing Java programs
– They follow the same principles