Unit Tests

CCNx NS3 Unit Test Conventions

We use the NS3 xUnit-style unit testing framework, but have added a few extra macros and functions to make writing tests easier! We like unit tests, so there are a lot of them.

Location

We use an out-of-source tree directory ccnx/test for all the unit tests. This directory follows the same structure as ccnx/model, so each subdirectory under model has a corresponding subdirectory under test. We aim for every source code module (.cc file except examples) having a corresponding unit test module and for reasonable unit test coverage.

Unit test macros

The header ccnx/test/TestMacros.h defines the BeginTest() and EndTest() macros. These wrap the creation of the derived ns3::TestCase class to reduce the clutter in a test suite with many tests.

For example, to test a class Foo, the test suite would look like this:

 namespace TestSuiteFoo {
   BeginTest(TestGetVersion)
     {
         printf("DoRun Test GetVersion() method\n");
         NS_TEST_EXPECT_MSG_EQ (true, true, "The truth");
     }
   EndTest()
  
   static class TestSuiteFoo : public TestSuite
   {
   public:
     TestSuiteFoo() : TestSuite ("TestSuiteFoo", UNIT)
       {
         AddTestCase (new TestGetVersion (), TestCase::QUICK);
       }
   } g_TestSuiteFoo;
   
 }; // namespace

Conventions

• A TestSuite is made up of TestCase classes and a TestSuite class that wraps them together.
• Because all tests are compiled in to the same library, all TestCase and TestSuite must have unique names.
• In a test module for class CCNxFoo:
  • Use a namespace to wrap all unit tests and the test suite. Name it ns3::ccnx::CCNxFooTests.
  • Use BeginTest() and EndTest() to wrap the TestCase classes. To test a method named Bar, use a name like TestBar or TestBar_ConditionX and TestBar_ConditionY.
  • Use a TestSuite named TestSuiteCCNxFoo and a global variable g_TestSuiteCCNxFoo.