Why is this an issue?
Nested if, for, do, while, switch and try statements is a key
ingredient for making what’s known as "Spaghetti code".
Such code is hard to read, refactor and therefore maintain.
Noncompliant code example
With the default threshold of 3:
if (condition1) { // Compliant; depth = 1
/* ... */
if (condition2) { // Compliant; depth = 2
/* ... */
for(int i = 0; i < 10; i++) { // Compliant; depth = 3, not exceeding the limit
/* ... */
if (condition4) { // Noncompliant; depth = 4
if (condition5) { // Depth = 5, exceeding the limit, but issues are only reported on depth = 4
/* ... */
}
return;
}
}
}
}
Exceptions
Each use of a macro containing control flow statements is counted as one nesting level, even if the macro contains more than one control flow
statement.
#define FOREACH(V,ARR) if(ARR!=nullptr) for(int V=0; V<(sizeof(ARR)/sizeof(ARR[0])); V++)
if (condition1) { // Compliant; depth = 1
if (condition2) { // Compliant; depth = 2
FOREACH(i, arr) { // Compliant; depth = 3 (not 4)
if (condition3) { // Noncompliant; depth = 4
/* ... */
}
}
}
}
