Why is this an issue?

Cognitive Complexity Complexity is a measure of how hard the control flow of a method is to understand.

Methods with high Cognitive Complexity will be difficult to maintain.

Function Abs(ByVal n As Integer) As Integer ' Noncompliant: cognitive complexity = 5
    If n >= 0 Then    ' +1
        Return n
    Else              ' +2, due to nesting
        If n = Integer.MinValue Then      ' +1
            Throw New ArgumentException("The absolute value of int.MinValue is outside of int boundaries")
        Else                              ' +1
            Return -n
        End If
    End If
End Function

They should be refactored to have lower complexity:

Function Abs(ByVal n As Integer) As Integer  ' Compliant: cognitive complexity = 3
    If n = Integer.MinValue Then    ' +1
        Throw New ArgumentException("The absolute value of int.MinValue is outside of int boundaries")
    Else If n >= 0 Then             ' +1
        Return n
    Else                            ' +1
        Return -n
    End If
End Function

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