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<overview>

<p>This metric measures the total cyclomatic complexity for the functions in a file.

</p>

<p>

Cyclomatic complexity approximates the number of paths that can be taken during the execution of a

function (and hence, the minimum number of tests cases necessary to test it thoroughly). Straight-line

code has zero cyclomatic complexity, while branches and loops increase cyclomatic complexity.</p>

<p>Files that contain too many complex functions can be difficult to test, understand, and maintain.</p>

</overview>

<recommendation>

<p>Try to simplify overly-complex code. For example:</p>

<ul><li>Highly nested conditionals can be simplified by rethinking the requirements that the function fulfills.</li>

<li>Repeated tests can be refactored into helper functions, which also decreases the risk of

introducing defects by copying and pasting code.</li>

<li>Large complex functions can often be split into smaller more focused functions.</li>

</ul>

</recommendation>

<references>

<li>M. Fowler. <em>Refactoring</em>. Addison-Wesley, 1999.</li>

<li>T. J. McCabe. <em>A Complexity Measure</em>. IEEE Transactions on Software Engineering, SE-2(4),

December 1976.</li>

<li>Wikipedia: <a href="http://en.wikipedia.org/wiki/Cyclomatic_complexity">Cyclomatic complexity</a>.</li>

</references>

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