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• Perform more comprehensive testing with existing resources: Flow Analysis complements other testing techniques by allowing you to find problems that would otherwise require the development, execution, and maintenance of complex test cases. Flow Analysis investigates various branching possibilities in a program, providing a level of path coverage that is difficult to accomplish with traditional testing. As a result, Flow Analysis often identifies problems that occur while handling rare situations that are typically not covered during testing. Moreover, if the code functionality changes, you can search for bugs in the modified version without updating or regenerating test cases.
• Automatically identify bugs that pass through multiple units: Traditional automated unit test generation helps you identify the bugs within a single compilation unit. This is critical. Yet, most developers have performed thorough unit-level testing, corrected all apparent problems, integrated the code, then later encountered problems, such as null pointer dereferencing, that took days to diagnose because they resulted from an obscure or complex execution path that passed through multiple functions or even multiple compilation units Using Flow Analysis, the same problem could be identified automatically 

• Focus on actual bugs and design flaws: Flow Analysis automatically identifies data-dependent or flow-dependent bugs with reasonable certainty. When Flow Analysis reports a violation, it is often the case that there was a design flaw and this manifested itself as simple violation such as a division by zero or a resource leak.

  For example, Flow Analysis would not report a violation for the following code unless there was a method calling calculateBufferLength and passing it a null pointer:

  Code Block
  int calculateBufferLength(char* str) {             return strlen(str) + 1; }

• Find API misuses: Many of the bugs in practice are due to calling some API with wrong  arguments or not properly handling the values returned by the API. For example, an API  may be expecting a non-null argument for parameter 2, when parameter 1 is true, or the API may potentially set some field in an object to null. By performing interprocedural analysis, Flow Analysis can point out inconsistencies in the usage of such API.

For details on using BugDetective, see See Flow Analysis for details.

Unit Testing

"Unit testing" refers to testing software code at the simplest functional point, which is typically a single class or a function. Unit testing is typically performed by developers inside a development cycle, rather than in the QA phase. Using unit testing, you can ensure that the application building blocks are solid before they are integrated, thus improving the quality of the entire application. When you test early, it is typically less difficult and time-consuming to identify and fix defects at this point.

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