Why is this an issue?
Conditional expressions which are always true or false can lead to dead code. Such code is always buggy and should never
be used in production.
Noncompliant code example
public void Sample(bool b)
{
bool a = false;
if (a) // Noncompliant
{
DoSomething(); // never executed
}
if (!a || b) // Noncompliant; "!a" is always "true", "b" is never evaluated
{
DoSomething();
}
else
{
DoSomethingElse(); // never executed
}
var d = "xxx";
var res = d ?? "value"; // Noncompliant, d is always not null, "value" is never used
}
Compliant solution
public void Sample(bool b)
{
bool a = false;
if (Foo(a))
{
DoSomething();
}
if (b)
{
DoSomething();
}
else
{
DoSomethingElse();
}
var d = "xxx";
var res = d;
}
Exceptions
This rule will not raise an issue in either of these cases:
- When the condition is a single
const bool
const bool debug = false;
//...
if (debug)
{
// Print something
}
- When the condition is the literal
true or false.
In these cases it is obvious the code is as intended.
Resources
