Cyclomatic complexity

Cyclomatic complexity is a software metric used to indicate the complexity of a computer program.

Description

Cyclomatic complexity is a quantitative measure of the number of linearly independent paths through a program's source code.

Cyclomatic complexity is computed using the control flow graph of the program:

• The nodes of the graph correspond to indivisible groups of commands of a program
• A directed edge connects two nodes if the second command might be executed immediately after the first command

Cyclomatic complexity may also be applied to individual functions, modules, methods or classes within a program.

Basis path testing

One testing strategy, called basis path testing by McCabe who first proposed it, is to test each linearly independent path through the program; in this case, the number of test cases will equal the cyclomatic complexity of the program.

History

It was developed by Thomas J. McCabe, Sr. in 1976.

See also

• Code refactoring
• Complexity trap - see Feature creep
• Computer program
• Computer programming
• Control flow
• Decision-to-decision path
• Design predicates
• Essential complexity (numerical measure of "structuredness")
• Feature creep
• Halstead complexity measures
• Maintainability
• Software engineering
• Software testing
• Static program analysis
• Synchronization complexity

External links

• Cyclomatic complexity @ Wikipedia