rspec/rules/S5633/python/rule.adoc

Dictionary unpacking requires an object with methods ``++__getitem__++`` and ``++keys++`` or ``++__getitem__++`` and ``++__getattr__++``. This is the case for any https://docs.python.org/3/glossary.html#term-mapping[mapping] object such as ``++dict++``. Using an object which doesn't have these methods will raise a ``++TypeError++``.


== Noncompliant Code Example

[source,python]
----
class A:
    pass

dict(**A())  # Noncompliant
{'a': 10, 'b': 20, **A()}  # Noncompliant 
----


== Compliant Solution

[source,python]
----
class A:
  def __getitem__(self, key):
      return 2

  def keys(self):
      return ['1','2','3']

dict(**A())  # => {'1': 2, '2': 2, '3': 2}
{'a': 10, 'b': 20, **A()}  # => {'a': 10, 'b': 20, '1': 2, '2': 2, '3': 2}
----

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

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

include::message.adoc[]

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