== Why is this an issue?

include::../description.adoc[]

Code like

[source,ruby]
----
if a then
  unless b then  # Noncompliant
    # ...
  end
end
----

Will be more readable as

[source, ruby]
----
if a && !b then  # Compliant
  # ...
end
----


== How to fix it

If merging the conditions seems to result in a more complex code, extracting the condition or part of it in a named function or variable is a better approach to fix readability.

=== Code examples

==== Noncompliant code example

[source,ruby]
----
if !filename.nil?
  if File.file?(filename) || File.directory?(filename) # Noncompliant
    # ...
  end
end
----

==== Compliant solution

[source,ruby]
----
def isFileOrDirectory(filename)
  File.file?(filename) || File.directory?(filename)
end
# ...

if !filename.nil? && isFileOrDirectory(filename)       # Compliant
  # ...
end
----

ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

include::../message.adoc[]

include::../highlighting.adoc[]

'''
== Comments And Links
(visible only on this page)

include::../comments-and-links.adoc[]

endif::env-github,rspecator-view[]