[Close #856] implement repeated example group description/body cops

CHANGELOG.md

@@ -5,6 +5,8 @@
 * Fix `RSpec/InstanceVariable` detection inside custom matchers. ([@pirj][])
 * Fix `RSpec/ScatteredSetup` to distinguish hooks with different metadata. ([@pirj][])
 * Add autocorrect support for `RSpec/ExpectActual` cop. ([@dduugg][], [@pirj][])
+* Add `RSpec/RepeatedExampleGroupBody` cop. ([@lazycoder9][])
+* Add `RSpec/RepeatedExampleGroupDescription` cop. ([@lazycoder9][])
 
 ## 1.37.1 (2019-12-16)
 
@@ -477,3 +479,4 @@ Compatibility release so users can upgrade RuboCop to 0.51.0. No new features.
 [@jfragoulis]: https://github.com/jfragoulis
 [@ybiquitous]: https://github.com/ybiquitous
 [@dduugg]: https://github.com/dduugg
+[@lazycoder9]: https://github.com/lazycoder9

config/default.yml

@@ -394,6 +394,16 @@ RSpec/RepeatedExample:
   Description: Check for repeated examples within example groups.
   StyleGuide: https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExample
 
+RSpec/RepeatedExampleGroupBody:
+  Enabled: true
+  Description: Check for repeated describe and context block body.
+  StyleGuide: https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExampleGroupBody
+
+RSpec/RepeatedExampleGroupDescription:
+  Enabled: true
+  Description: Check for repeated example group descriptions.
+  StyleGuide: https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExampleGroupDescription
+
 RSpec/ReturnFromStub:
   Enabled: true
   Description: Checks for consistent style of stub's return setting.

lib/rubocop/cop/rspec/repeated_example_group_body.rb

@@ -0,0 +1,87 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module RSpec
+      # Check for repeated describe and context block body.
+      #
+      # @example
+      #
+      #    # bad
+      #    describe 'cool feature x' do
+      #      it { cool_predicate }
+      #    end
+      #
+      #    describe 'cool feature y' do
+      #      it { cool_predicate }
+      #    end
+      #
+      #    # good
+      #    describe 'cool feature' do
+      #      it { cool_predicate }
+      #    end
+      #
+      #    describe 'another cool feature' do
+      #      it { another_predicate }
+      #    end
+      #
+      #    # good
+      #    context 'when case x', :tag do
+      #      it { cool_predicate }
+      #    end
+      #
+      #    context 'when case y' do
+      #      it { cool_predicate }
+      #    end
+      #
+      class RepeatedExampleGroupBody < Cop
+        MSG = 'Repeated %<group>s block body on line(s) %<loc>s'
+
+        def_node_matcher :several_example_groups?, <<-PATTERN
+          (begin <#example_group_with_body? #example_group_with_body? ...>)
+        PATTERN
+
+        def_node_matcher :metadata, '(block (send _ _ _ $...) ...)'
+        def_node_matcher :body, '(block _ args $...)'
+
+        def_node_matcher :skip_or_pending?, <<-PATTERN
+          (block <(send nil? {:skip :pending}) ...>)
+        PATTERN
+
+        def on_begin(node)
+          return unless several_example_groups?(node)
+
+          repeated_group_bodies(node).each do |group, repeats|
+            add_offense(group, message: message(group, repeats))
+          end
+        end
+
+        private
+
+        def repeated_group_bodies(node)
+          node
+            .children
+            .select { |child| example_group_with_body?(child) }
+            .reject { |child| skip_or_pending?(child) }
+            .group_by { |group| signature_keys(group) }
+            .values
+            .reject(&:one?)
+            .flat_map { |groups| add_repeated_lines(groups) }
+        end
+
+        def add_repeated_lines(groups)
+          repeated_lines = groups.map(&:first_line)
+          groups.map { |group| [group, repeated_lines - [group.first_line]] }
+        end
+
+        def signature_keys(group)
+          [metadata(group), body(group)]
+        end
+
+        def message(group, repeats)
+          format(MSG, group: group.method_name, loc: repeats)
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/rspec/repeated_example_group_description.rb

@@ -0,0 +1,96 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module RSpec
+      # Check for repeated example group descriptions.
+      #
+      # @example
+      #
+      #    # bad
+      #    describe 'cool feature' do
+      #      # example group
+      #    end
+      #
+      #    describe 'cool feature' do
+      #      # example group
+      #    end
+      #
+      #    # bad
+      #    context 'when case x' do
+      #      # example group
+      #    end
+      #
+      #    describe 'when case x' do
+      #      # example group
+      #    end
+      #
+      #    # good
+      #    describe 'cool feature' do
+      #      # example group
+      #    end
+      #
+      #    describe 'another cool feature' do
+      #      # example group
+      #    end
+      #
+      #    # good
+      #    context 'when case x' do
+      #      # example group
+      #    end
+      #
+      #    context 'when another case' do
+      #      # example group
+      #    end
+      #
+      class RepeatedExampleGroupDescription < Cop
+        MSG = 'Repeated %<group>s block description on line(s) %<loc>s'
+
+        def_node_matcher :several_example_groups?, <<-PATTERN
+          (begin <#example_group? #example_group? ...>)
+        PATTERN
+
+        def_node_matcher :doc_string_and_metadata, <<-PATTERN
+          (block (send _ _ $_ $...) ...)
+        PATTERN
+
+        def_node_matcher :skip_or_pending?, <<-PATTERN
+          (block <(send nil? {:skip :pending}) ...>)
+        PATTERN
+
+        def_node_matcher :empty_description?, '(block (send _ _) ...)'
+
+        def on_begin(node)
+          return unless several_example_groups?(node)
+
+          repeated_group_descriptions(node).each do |group, repeats|
+            add_offense(group, message: message(group, repeats))
+          end
+        end
+
+        private
+
+        def repeated_group_descriptions(node)
+          node
+            .children
+            .select { |child| example_group?(child) }
+            .reject { |child| skip_or_pending?(child) }
+            .reject { |child| empty_description?(child) }
+            .group_by { |group| doc_string_and_metadata(group) }
+            .values
+            .reject(&:one?)
+            .flat_map { |groups| add_repeated_lines(groups) }
+        end
+
+        def add_repeated_lines(groups)
+          repeated_lines = groups.map(&:first_line)
+          groups.map { |group| [group, repeated_lines - [group.first_line]] }
+        end
+
+        def message(group, repeats)
+          format(MSG, group: group.method_name, loc: repeats)
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/rspec_cops.rb

@@ -74,6 +74,8 @@
 require_relative 'rspec/receive_never'
 require_relative 'rspec/repeated_description'
 require_relative 'rspec/repeated_example'
+require_relative 'rspec/repeated_example_group_body'
+require_relative 'rspec/repeated_example_group_description'
 require_relative 'rspec/return_from_stub'
 require_relative 'rspec/scattered_let'
 require_relative 'rspec/scattered_setup'

manual/cops.md

@@ -73,6 +73,8 @@
 * [RSpec/ReceiveNever](cops_rspec.md#rspecreceivenever)
 * [RSpec/RepeatedDescription](cops_rspec.md#rspecrepeateddescription)
 * [RSpec/RepeatedExample](cops_rspec.md#rspecrepeatedexample)
+* [RSpec/RepeatedExampleGroupBody](cops_rspec.md#rspecrepeatedexamplegroupbody)
+* [RSpec/RepeatedExampleGroupDescription](cops_rspec.md#rspecrepeatedexamplegroupdescription)
 * [RSpec/ReturnFromStub](cops_rspec.md#rspecreturnfromstub)
 * [RSpec/ScatteredLet](cops_rspec.md#rspecscatteredlet)
 * [RSpec/ScatteredSetup](cops_rspec.md#rspecscatteredsetup)

manual/cops_rspec.md

@@ -2552,6 +2552,101 @@ end
 
 * [https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExample](https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExample)
 
+## RSpec/RepeatedExampleGroupBody
+
+Enabled by default | Supports autocorrection
+--- | ---
+Enabled | No
+
+Check for repeated describe and context block body.
+
+### Examples
+
+```ruby
+# bad
+describe 'cool feature x' do
+  it { cool_predicate }
+end
+
+describe 'cool feature y' do
+  it { cool_predicate }
+end
+
+# good
+describe 'cool feature' do
+  it { cool_predicate }
+end
+
+describe 'another cool feature' do
+  it { another_predicate }
+end
+
+# good
+context 'when case x', :tag do
+  it { cool_predicate }
+end
+
+context 'when case y' do
+  it { cool_predicate }
+end
+```
+
+### References
+
+* [https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExampleGroupBody](https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExampleGroupBody)
+
+## RSpec/RepeatedExampleGroupDescription
+
+Enabled by default | Supports autocorrection
+--- | ---
+Enabled | No
+
+Check for repeated example group descriptions.
+
+### Examples
+
+```ruby
+# bad
+describe 'cool feature' do
+  # example group
+end
+
+describe 'cool feature' do
+  # example group
+end
+
+# bad
+context 'when case x' do
+  # example group
+end
+
+describe 'when case x' do
+  # example group
+end
+
+# good
+describe 'cool feature' do
+  # example group
+end
+
+describe 'another cool feature' do
+  # example group
+end
+
+# good
+context 'when case x' do
+  # example group
+end
+
+context 'when another case' do
+  # example group
+end
+```
+
+### References
+
+* [https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExampleGroupDescription](https://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/RepeatedExampleGroupDescription)
+
 ## RSpec/ReturnFromStub
 
 Enabled by default | Supports autocorrection