Integration testing

Bottom Up Integration

1. Combine a cluster of modules that perform a sub-function

2. Develop a "driver" to test the cluster

3. Combine clusters and move upward

4. Finally, interface with top control module

This approach has the advantage that "worker" modules are tested early, and there is no need for stubs and/or dummy simulation of data

Drivers and Stubs

If you want to test modules A, B, and C, the test program is the driver.

If module A exists but B and C do not exist, B and C are replaced by stubs (a dummy program that does nothing exceept announcing it is being invoked) so that you can test module A without having modules B and C.