else block after a branch that always diverges

Reports an else block whose matching if branch ends in return, break, continue or a panicking macro, so control can only reach the else when the condition is false anyway.

The else adds a level of indentation and a second branch to follow for a decision the return has already made, and every statement after it inherits that nesting. Guard clauses read the other way round: the exceptional case is handled and dismissed at the top, and the rest of the function is the normal path at one level of indentation.

The following code illustrates the pattern detected by this rule:

Drop the else and outdent its body - if bad { return x; } else { y } becomes if bad { return x; } y. For an else if chain, the following conditions become plain if statements once the diverging branch no longer needs an alternative.

This detector does not need any configuration.