10.5 Integration Testing
10.5.1 Fundamentals
The basic ideas of software integration and integration testing were spelled out earlier in Section 10.1. Let's return to this issue, to look at the general aspects of the testing of integrated units. The ideas are generally applicable to all the levels and units of the software shown in Figure 10.4. In practice, a variety of units are likely to be used, including software machines, modules, objects, components, and tasks. The one item that stands out as being different is an object within an inheritance structure; this is dealt with separately in the section on OO testing. Clearly, test details will depend on the precise nature of the individual software units.
Three integration techniques in general use are the following:
- Big-bang approach. All integration and testing is executed in a single phase.
- Top-down incremental route.
- Bottom-up incremental path.
The big-bang method has been pretty well discredited...