Nested If

go.nested_if

Severity

low

Remediation Complexity

medium

Remediation Risk

low

Remediation Effort

medium

Resource

Code Smell

Language

Description

Reports an if statement whose nesting depth within the enclosing function exceeds the configurable maxDepth threshold (default: 4). An else if chain is parsed as siblings of the same if, not as a nested statement, so a long ladder does not raise the depth — only genuinely nested if bodies do.

Rationale

Deeply nested conditionals are hard to read, understand, and test. Each nesting level adds a new mental stack frame and multiplies the number of execution paths. Refactoring toward early returns, guard clauses, or extracted helper functions eliminates the nesting and makes the intent clear.

// Bad — 5 levels deep
func check(a, b, c, d, e int) string {
    if a > 0 {
        if b > 0 {
            if c > 0 {
                if d > 0 {
                    if e > 0 { // FLAW
                        return "all positive"
                    }
                }
            }
        }
    }
    return "other"
}

// Good — guard clause flattens the nesting
func check(a, b, c, d, e int) string {
    if a <= 0 || b <= 0 || c <= 0 || d <= 0 || e <= 0 {
        return "other"
    }
    return "all positive"
}

Remediation

Use early returns or guard clauses to reduce nesting. If the logic is inherently complex, extract sub-conditions into named helper functions.

References

Effective Go