Merge pull request #932 from andrykonchin/add-top-level-group-callback

RSpec/SubjectStub. Add top level group callback

Author: pirj

lib/rubocop-rspec.rb

@@ -13,6 +13,7 @@
 require_relative 'rubocop/rspec/wording'
 require_relative 'rubocop/rspec/language'
 require_relative 'rubocop/rspec/language/node_pattern'
+require_relative 'rubocop/rspec/top_level_group'
 require_relative 'rubocop/rspec/concept'
 require_relative 'rubocop/rspec/example_group'
 require_relative 'rubocop/rspec/example'

lib/rubocop/cop/rspec/subject_stub.rb

@@ -22,6 +22,8 @@ module RSpec
       #   end
       #
       class SubjectStub < Cop
+        include RuboCop::RSpec::TopLevelGroup
+
         MSG = 'Do not stub methods of the object under test.'
 
         # @!method subject(node)
@@ -75,11 +77,7 @@ class SubjectStub < Cop
             } ...)
         PATTERN
 
-        def on_block(node)
-          return unless example_group?(node)
-          return if (processed_example_groups & node.ancestors).any?
-
-          processed_example_groups << node
+        def on_top_level_group(node)
           @explicit_subjects = find_all_explicit_subjects(node)
 
           find_subject_expectations(node) do |stub|
@@ -89,10 +87,6 @@ def on_block(node)
 
         private
 
-        def processed_example_groups
-          @processed_example_groups ||= Set.new
-        end
-
         def find_all_explicit_subjects(node)
           node.each_descendant(:block).with_object({}) do |child, h|
             name = subject(child)

lib/rubocop/rspec/top_level_group.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module RSpec
+    # Helper methods for top level example group cops
+    module TopLevelGroup
+      extend RuboCop::NodePattern::Macros
+      include RuboCop::RSpec::Language
+
+      def_node_matcher :example_or_shared_group?,
+                       (ExampleGroups::ALL + SharedGroups::ALL).block_pattern
+
+      def on_block(node)
+        return unless respond_to?(:on_top_level_group)
+        return unless top_level_group?(node)
+
+        on_top_level_group(node)
+      end
+
+      private
+
+      def top_level_group?(node)
+        top_level_groups.include?(node)
+      end
+
+      def top_level_groups
+        @top_level_groups ||=
+          top_level_nodes.select { |n| example_or_shared_group?(n) }
+      end
+
+      def top_level_nodes
+        if root_node.begin_type?
+          root_node.children
+        else
+          [root_node]
+        end
+      end
+
+      def root_node
+        processed_source.ast
+      end
+    end
+  end
+end

spec/rubocop/cop/rspec/subject_stub_spec.rb

@@ -321,4 +321,46 @@
       end
     RUBY
   end
+
+  it 'flags when there are several top level example groups' do
+    expect_offense(<<-RUBY)
+      RSpec.describe Foo do
+        subject(:foo) { described_class.new }
+
+        specify do
+          expect(foo).to eq(foo)
+        end
+      end
+
+      RSpec.describe Bar do
+        subject(:bar) { described_class.new }
+
+        specify do
+          allow(bar).to receive(:bar)
+          ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Do not stub methods of the object under test.
+        end
+      end
+    RUBY
+  end
+
+  describe 'top level example groups' do
+    %i[
+      describe xdescribe fdescribe
+      context xcontext fcontext
+      feature xfeature ffeature
+      example_group
+      shared_examples shared_examples_for shared_context
+    ].each do |method|
+      it "flags in top level #{method}" do
+        expect_offense(<<-RUBY)
+          RSpec.#{method} '#{method}' do
+            it 'uses an implicit subject' do
+              expect(subject).to receive(:bar)
+              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Do not stub methods of the object under test.
+            end
+          end
+        RUBY
+      end
+    end
+  end
 end