Fix an exception in DescribedClass when accessing a constant on a variable in a namespaced spec

Author: rrosenblum

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Master (Unreleased)
 
 * Add missing documentation for `single_statement_only` style of `RSpec/ImplicitSubject` cop. ([@tejasbubane][])
+* Fix an exception in `DescribedClass` when accessing a constant on a variable in a spec that is nested in a namespace. ([@rrosenblum][])
 
 ## 2.3.0 (2021-04-28)
 
@@ -615,3 +616,4 @@ Compatibility release so users can upgrade RuboCop to 0.51.0. No new features.
 [@hosamaly]: https://github.com/hosamaly
 [@stephannv]: https://github.com/stephannv
 [@Tietew]: https://github.com/Tietew
+[@rrosenblum]: https://github.com/rrosenblum

lib/rubocop/cop/rspec/described_class.rb

@@ -203,7 +203,7 @@ def const_name(node)
             [name]
           elsif namespace.const_type?
             [*const_name(namespace), name]
-          elsif namespace.lvar_type? || namespace.cbase_type?
+          elsif %i[lvar cbase send].include?(namespace.type)
             [nil, name]
           end
         end

spec/rubocop/cop/rspec/described_class_spec.rb

@@ -77,6 +77,17 @@
       RUBY
     end
 
+    it 'allows accessing constants from variables when in a nested namespace' do
+      expect_no_offenses(<<~RUBY)
+        module Foo
+          describe MyClass do
+            let(:foo) { SomeClass }
+            let(:baz) { foo::CONST }
+          end
+        end
+      RUBY
+    end
+
     it 'flags with metadata' do
       expect_offense(<<-RUBY)
         describe MyClass, some: :metadata do