rspec/rules/S1871/python/rule.adoc

Having two branches in the same `+if+` structure  with the same implementation is at best duplicate code, and at worst a coding error. If the same logic is truly needed for both instances, then they should be combined.

== Noncompliant Code Example

----
if 0 <= a < 10:
    do_first()
    do_second()
elif 10 <= a < 20:
    do_the_other_thing()
elif 20 <= a < 50:
    do_first()         # Noncompliant; duplicates first condition
    do_second()  
----

== Exceptions

Blocks in an `+if+` chain that contain a single line of code are ignored.

----
if 0 <= a < 10:
    do_first()
elif 10 <= a < 20:
    do_the_other_thing()
elif 20 <= a < 50:
    do_first()         # no issue, usually this is done on purpose to increase the readability
----

But this exception does not apply to `+if+` chains without `+else+`-s when all branches have the same single line of code. In case of `+if+` chains with `+else+`-s rule S3923 raises a bug. 

----
if 0 <= a < 10:
    do_first()
elif 20 <= a < 50:
    do_first()         # Noncompliant, this might have been done on purpose but probably not
----