Credo
Credo v1.6.4

View Source Credo.Check.Refactor.NegatedConditionsInUnless (Credo v1.6.4)

This check has a base priority of high and works with any version of Elixir.

Explanation

Unless blocks should avoid having a negated condition.

The code in this example ...

unless !allowed? do
  proceed_as_planned()
end

... should be refactored to look like this:

if allowed? do
  proceed_as_planned()
end

The reason for this is not a technical but a human one. It is pretty difficult to wrap your head around a block of code that is executed if a negated condition is NOT met. See what I mean?

Check-Specific Parameters

There are no specific parameters for this check.

General Parameters

Like with all checks, general params can be applied.

Parameters can be configured via the .credo.exs config file.