Merge pull request #831 from kellysutton/ks-nested-module-cop

Implement RSpec/DescribedClassModuleWrapping cop

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Master (Unreleased)
 
+* Implement `RSpec/DescribedClassModuleWrapping` to disallow RSpec statements within a module. ([@kellysutton][])
 * Fix documentation rake task to support Rubocop 0.75. ([@nickcampbell18][])
 * Fix `RSpec/SubjectStub` to detect implicit subjects stubbed. ([@QQism][])
 
@@ -457,3 +458,4 @@ Compatibility release so users can upgrade RuboCop to 0.51.0. No new features.
 [@onumis]: https://github.com/onumis
 [@nickcampbell18]: https://github.com/nickcampbell18
 [@QQism]: https://github.com/QQism
+[@kellysutton]: https://github.com/kellysutton

config/default.yml

@@ -88,6 +88,11 @@ RSpec/DescribedClass:
   - explicit
   StyleGuide: https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/DescribedClass
 
+RSpec/DescribedClassModuleWrapping:
+  Description: Avoid opening modules and defining specs within them.
+  Enabled: false
+  StyleGuide: https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/DescribedClassModuleWrapping
+
 RSpec/Dialect:
   Description: This cop enforces custom RSpec dialects.
   Enabled: false

lib/rubocop/cop/rspec/described_class_module_wrapping.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module RSpec
+      # Avoid opening modules and defining specs within them.
+      #
+      # @example
+      #   # bad
+      #   module MyModule
+      #     RSpec.describe MyClass do
+      #       # ...
+      #     end
+      #   end
+      #
+      #   # good
+      #   RSpec.describe MyModule::MyClass do
+      #     # ...
+      #   end
+      #
+      # @see https://github.com/rubocop-hq/rubocop-rspec/issues/735
+      class DescribedClassModuleWrapping < Cop
+        MSG = 'Avoid opening modules and defining specs within them.'
+
+        def_node_search :find_rspec_blocks,
+                        ExampleGroups::ALL.block_pattern
+
+        def on_module(node)
+          find_rspec_blocks(node) do
+            add_offense(node)
+          end
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/rspec_cops.rb

@@ -25,6 +25,7 @@
 require_relative 'rspec/describe_method'
 require_relative 'rspec/describe_symbol'
 require_relative 'rspec/described_class'
+require_relative 'rspec/described_class_module_wrapping'
 require_relative 'rspec/dialect'
 require_relative 'rspec/empty_example_group'
 require_relative 'rspec/empty_line_after_example'

manual/cops.md

@@ -24,6 +24,7 @@
 * [RSpec/DescribeMethod](cops_rspec.md#rspecdescribemethod)
 * [RSpec/DescribeSymbol](cops_rspec.md#rspecdescribesymbol)
 * [RSpec/DescribedClass](cops_rspec.md#rspecdescribedclass)
+* [RSpec/DescribedClassModuleWrapping](cops_rspec.md#rspecdescribedclassmodulewrapping)
 * [RSpec/Dialect](cops_rspec.md#rspecdialect)
 * [RSpec/EmptyExampleGroup](cops_rspec.md#rspecemptyexamplegroup)
 * [RSpec/EmptyLineAfterExample](cops_rspec.md#rspecemptylineafterexample)

manual/cops_rspec.md

@@ -469,6 +469,34 @@ EnforcedStyle | `described_class` | `described_class`, `explicit`
 
 * [https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/DescribedClass](https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/DescribedClass)
 
+## RSpec/DescribedClassModuleWrapping
+
+Enabled by default | Supports autocorrection
+--- | ---
+Disabled | No
+
+Avoid opening modules and defining specs within them.
+
+### Examples
+
+```ruby
+# bad
+module MyModule
+  RSpec.describe MyClass do
+    # ...
+  end
+end
+
+# good
+RSpec.describe MyModule::MyClass do
+  # ...
+end
+```
+
+### References
+
+* [https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/DescribedClassModuleWrapping](https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/DescribedClassModuleWrapping)
+
 ## RSpec/Dialect
 
 Enabled by default | Supports autocorrection

spec/rubocop/cop/rspec/described_class_module_wrapping_spec.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+RSpec.describe RuboCop::Cop::RSpec::DescribedClassModuleWrapping do
+  subject(:cop) { described_class.new }
+
+  it 'allows a describe block in the outermost scope' do
+    expect_no_offenses(<<-RUBY)
+      RSpec.describe MyClass do
+        subject { "MyClass" }
+      end
+    RUBY
+  end
+
+  it 'registers an offense when RSpec.describe is nested within a module' do
+    expect_offense(<<-RUBY)
+      module MyModule
+      ^^^^^^^^^^^^^^^ Avoid opening modules and defining specs within them.
+        RSpec.describe MyClass do
+
+          subject { "MyClass" }
+        end
+      end
+    RUBY
+  end
+
+  it 'registers an offense when RSpec.describe is nested within two modules' do
+    expect_offense(<<-RUBY)
+      module MyFirstModule
+      ^^^^^^^^^^^^^^^^^^^^ Avoid opening modules and defining specs within them.
+        module MySecondModule
+        ^^^^^^^^^^^^^^^^^^^^^ Avoid opening modules and defining specs within them.
+          RSpec.describe MyClass do
+
+            subject { "MyClass" }
+          end
+        end
+      end
+    RUBY
+  end
+
+  it 'allows a module that does not contain RSpec.describe' do
+    expect_no_offenses(<<-RUBY)
+      module MyModule
+        def some_method
+        end
+      end
+    RUBY
+  end
+end