The simple interpretation is that the cyclomatic complexity is an upper bound for the number of test cases required to obtain branch coverage of the code. So I would say that you should count it as additional complexity. It was developed by Thomas J. McCabe, Sr. in 1976. It is a measure that provides an idea of the logical complexity of a program. Cyclomatic complexity basically measures how much your code branches. If it is C, there is no nested for loop, but ratehr a while loop nested in a for loop. Cyclomatic complexity may be extended to a program with multiple exit points; in this case it is equal to: However, there is only one possible path of execution here. Control flow statements like return, break, and continue all play into the cyclomatic complexity of a menu and need to be accounted for. Both the while-loop and the do-while-loop add two to the complexity: According to this article cyclomatic complexity directly measures the number of linearly independent paths through a program's source code.. Now observe the following code: def f(): for i in range(10): print i This code outputs a complexity of 2 with the program.. – David Thornley Apr 19 '10 at 18:56. In my opinion, this is a valid use-case for this metric. You've added yet another branch with the if statement. Every time there’s an if statement or other control block like a loop, cyclomatic complexity goes up, since the graph will look more and more like a tree. Iteration – While loops. ... We have seen with the if-else-if construct, each else-if adds one to the complexity. Over the years, I have found one metric to be the simplest and most consistent indicator of code quality – Cyclomatic Complexity. Cyclomatic complexity is a source code complexity measurement that is being correlated to a number of coding errors. Cyclomatic complexity. Cyclomatic complexity coincides … It is calculated by developing a Control Flow Graph of the code that measures the number of linearly-independent paths through a program module. Go back to Tutorial Cyclomatic complexity is a software metric used to indicate the complexity of a program. Even though each iteration of the loop may or may not go into the block, we still account for the conditional only once. There's still a branch at the end of the loop that goes back to the beginning. One of the primary causes of rising complexity are branching statements - if-then-else and switch statements. Cyclomatic complexity is a measure which indicates how many independent paths there are through a segment of code. It can be shown that the cyclomatic complexity of any structured program with only one entrance point and one exit point is equal to the number of decision points (i.e., 'if' statements or conditional loops) contained in that program plus one. Cyclomatic complexity is a metric for the measurement of complexity of a software. By providing --no-static-loop option a user may specify that such loops should not be counted when computing the cyclomatic complexity metric The Ada essential complexity metric is a McCabe cyclomatic complexity metric counted for the code that is reduced by excluding all the pure structural Ada control statements. So, in the context of testing, cyclomatic complexity can be used to estimate the required effort for writing tests. It is a quantitative measure of the number of linearly independent paths through a program’s source code. I have to find cyclomatic complexity for this code and then suggest some white box test cases and black box test cases. This metric although widely cited has many limitations. It looks like C except for the "Int" rather than "int" in the declaration. Note also that we include loops with conditionals. 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