Add new cop BangPersistence

Author: aliismayilov

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 - Handle unknown HTTP status codes for `RSpecRails/HttpStatus` cop. ([@viralpraxis])
 - Fix a false negative for `RSpecRails/TravelAround` cop when passed as a proc to a travel method. ([@ydah])
+- Introduce new cop `RSpecRails/BangPersistence` cop. ([@aliismayilov])
 
 ## 2.30.0 (2024-06-12)
 
@@ -72,6 +73,7 @@
 <!-- Contributors (alphabetically) -->
 
 [@akiomik]: https://github.com/akiomik
+[@aliismayilov]: https://github.com/aliismayilov
 [@anthony-robin]: https://github.com/anthony-robin
 [@bquorning]: https://github.com/bquorning
 [@corydiamand]: https://github.com/corydiamand

config/default.yml

@@ -12,6 +12,13 @@ RSpecRails/AvoidSetupHook:
   VersionAdded: '2.4'
   Reference: https://www.rubydoc.info/gems/rubocop-rspec_rails/RuboCop/Cop/RSpecRails/AvoidSetupHook
 
+RSpecRails/BangPersistence:
+  Description: Prefer bang methods for persistence.
+  Enabled: pending
+  SafeAutoCorrect: false
+  VersionAdded: "<<next>>"
+  Reference: https://www.rubydoc.info/gems/rubocop-rspec_rails/RuboCop/Cop/RSpecRails/BangPersistence
+
 RSpecRails/HaveHttpStatus:
   Description: Checks that tests use `have_http_status` instead of equality matchers.
   Enabled: pending

docs/modules/ROOT/pages/cops.adoc

@@ -3,6 +3,7 @@
 === Department xref:cops_rspecrails.adoc[RSpecRails]
 
 * xref:cops_rspecrails.adoc#rspecrailsavoidsetuphook[RSpecRails/AvoidSetupHook]
+* xref:cops_rspecrails.adoc#rspecrailsbangpersistence[RSpecRails/BangPersistence]
 * xref:cops_rspecrails.adoc#rspecrailshavehttpstatus[RSpecRails/HaveHttpStatus]
 * xref:cops_rspecrails.adoc#rspecrailshttpstatus[RSpecRails/HttpStatus]
 * xref:cops_rspecrails.adoc#rspecrailsinferredspectype[RSpecRails/InferredSpecType]

docs/modules/ROOT/pages/cops_rspecrails.adoc

@@ -42,6 +42,51 @@ end
 
 * https://www.rubydoc.info/gems/rubocop-rspec_rails/RuboCop/Cop/RSpecRails/AvoidSetupHook
 
+[#rspecrailsbangpersistence]
+== RSpecRails/BangPersistence
+
+|===
+| Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed
+
+| Pending
+| Yes
+| Always (Unsafe)
+| <<next>>
+| -
+|===
+
+Prefer bang methods for persistence.
+
+[#safety-rspecrailsbangpersistence]
+=== Safety
+
+This cop is unsafe because by replacing non-bang versions
+of the persistence methods, you might:
+1. Catch persistence failures. This is what you want to catch.
+2. Might replace wrong object calls.
+   The cop is unaware if the object is ActiveRecord instance
+
+[#examples-rspecrailsbangpersistence]
+=== Examples
+
+[source,ruby]
+----
+# bad
+before do
+  post.update(title: "new title")
+end
+
+# good
+before do
+  post.update!(type: "new title")
+end
+----
+
+[#references-rspecrailsbangpersistence]
+=== References
+
+* https://www.rubydoc.info/gems/rubocop-rspec_rails/RuboCop/Cop/RSpecRails/BangPersistence
+
 [#rspecrailshavehttpstatus]
 == RSpecRails/HaveHttpStatus
 

lib/rubocop/cop/rspec_rails/bang_persistence.rb

@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module RSpecRails
+      # Prefer bang methods for persistence.
+      #
+      # @safety
+      #   This cop is unsafe because by replacing non-bang versions
+      #   of the persistence methods, you might:
+      #   1. Catch persistence failures. This is what you want to catch.
+      #   2. Might replace wrong object calls.
+      #      The cop is unaware if the object is ActiveRecord instance
+      #
+      #
+      # @example
+      #   # bad
+      #   before do
+      #     post.update(title: "new title")
+      #   end
+      #
+      #   # good
+      #   before do
+      #     post.update!(type: "new title")
+      #   end
+      #
+      class BangPersistence < ::RuboCop::Cop::Base
+        extend AutoCorrector
+
+        MSG = 'Prefer bang versions of the persistence methods.'
+
+        PERSISTENCE_METHODS = %i[
+          create
+          destroy
+          save
+          update
+          update_attribute
+        ].to_set.freeze
+
+        # Match `before` blocks
+        # @!method before_block?(node)
+        def_node_matcher :before_block?, <<-PATTERN
+          (block (send nil? :before) ...)
+        PATTERN
+
+        # Match `save` and `update` method calls
+        # @!method peristence_calls(node)
+        def_node_search :peristence_calls, <<-PATTERN
+          (send _ {#{PERSISTENCE_METHODS.map { |method| ":#{method}" }.join(' ')}} ...)
+        PATTERN
+
+        def on_block(node)
+          return unless before_block?(node)
+
+          peristence_calls(node) do |method_call|
+            add_offense(method_call) do |corrector|
+              corrector.replace(method_call.loc.selector,
+                                "#{method_call.method_name}!")
+            end
+          end
+        end
+
+        alias on_numblock on_block
+      end
+    end
+  end
+end

lib/rubocop/cop/rspec_rails_cops.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative 'rspec_rails/avoid_setup_hook'
+require_relative 'rspec_rails/bang_persistence'
 require_relative 'rspec_rails/have_http_status'
 require_relative 'rspec_rails/http_status'
 require_relative 'rspec_rails/inferred_spec_type'

spec/rubocop/cop/rspec_rails/bang_persistence_spec.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+RSpec.describe RuboCop::Cop::RSpecRails::BangPersistence do
+  context 'with `save!` in `before`' do
+    it 'registers no offense' do
+      expect_no_offenses(<<~RUBY)
+        before { post.save! }
+      RUBY
+    end
+  end
+
+  context 'with `update!` in `before`' do
+    it 'registers no offense' do
+      expect_no_offenses(<<~RUBY)
+        before { post.update!(title: "new title") }
+      RUBY
+    end
+  end
+
+  context 'with `save` in `before`' do
+    it 'registers offense' do
+      expect_offense(<<~RUBY)
+        before { post.save }
+                 ^^^^^^^^^ Prefer bang versions of the persistence methods.
+      RUBY
+
+      expect_correction(<<~RUBY)
+        before { post.save! }
+      RUBY
+    end
+  end
+
+  context 'with `update_attribute` in `before`' do
+    it 'registers offense' do
+      expect_offense(<<~RUBY)
+        before do
+          post.update_attribute(title: "new title")
+          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Prefer bang versions of the persistence methods.
+        end
+      RUBY
+
+      expect_correction(<<~RUBY)
+        before do
+          post.update_attribute!(title: "new title")
+        end
+      RUBY
+    end
+  end
+end