Add new Rails/SquishedSQLHeredocs cop

CHANGELOG.md

@@ -40,6 +40,7 @@
 
 ### New features
 
+* [#291](https://github.com/rubocop-hq/rubocop-rails/pull/291): Add new `Rails/SquishedSQLHeredocs` cop. ([@mobilutz][])
 * [#283](https://github.com/rubocop-hq/rubocop-rails/pull/283): Add new `Rails/FindById` cop. ([@fatkodima][])
 * [#285](https://github.com/rubocop-hq/rubocop-rails/pull/285): Add new `Rails/ActiveRecordCallbacksOrder` cop. ([@fatkodima][])
 * [#276](https://github.com/rubocop-hq/rubocop-rails/pull/276): Add new `Rails/RenderPlainText` cop. ([@fatkodima][])
@@ -269,3 +270,4 @@
 [@philcoggins]: https://github.com/philcoggins
 [@kunitoo]: https://github.com/kunitoo
 [@jaredmoody]: https://github.com/jaredmoody
+[@mobilutz]: https://github.com/mobilutz

config/default.yml

@@ -648,6 +648,12 @@ Rails/SkipsModelValidations:
     - upsert_all
   AllowedMethods: []
 
+Rails/SquishedSQLHeredocs:
+  Description: 'Checks SQL heredocs to use `.squish`.'
+  StyleGuide: 'https://rails.rubystyle.guide/#squished-heredocs'
+  Enabled: 'pending'
+  VersionAdded: '2.8'
+
 Rails/TimeZone:
   Description: 'Checks the correct usage of time zone aware methods.'
   StyleGuide: 'https://rails.rubystyle.guide#time'

docs/modules/ROOT/pages/cops.adoc

@@ -89,6 +89,7 @@ based on the https://rails.rubystyle.guide/[Rails Style Guide].
 * xref:cops_rails.adoc#railsscopeargs[Rails/ScopeArgs]
 * xref:cops_rails.adoc#railsshorti18n[Rails/ShortI18n]
 * xref:cops_rails.adoc#railsskipsmodelvalidations[Rails/SkipsModelValidations]
+* xref:cops_rails.adoc#railssquishedsqlheredocs[Rails/SquishedSQLHeredocs]
 * xref:cops_rails.adoc#railstimezone[Rails/TimeZone]
 * xref:cops_rails.adoc#railsuniqbeforepluck[Rails/UniqBeforePluck]
 * xref:cops_rails.adoc#railsuniquevalidationwithoutindex[Rails/UniqueValidationWithoutIndex]

docs/modules/ROOT/pages/cops_rails.adoc

@@ -3932,6 +3932,59 @@ user.touch
 
 * https://guides.rubyonrails.org/active_record_validations.html#skipping-validations
 
+== Rails/SquishedSQLHeredocs
+
+|===
+| Enabled by default | Safe | Supports autocorrection | VersionAdded | VersionChanged
+
+| Pending
+| Yes
+| Yes
+| 2.8
+| -
+|===
+
+Checks SQL heredocs to use `.squish`.
+
+=== Examples
+
+[source,ruby]
+----
+# bad
+<<-SQL
+  SELECT * FROM posts;
+SQL
+
+<<-SQL
+  SELECT * FROM posts
+    WHERE id = 1
+SQL
+
+execute(<<~SQL, "Post Load")
+  SELECT * FROM posts
+    WHERE post_id = 1
+SQL
+
+# good
+<<-SQL.squish
+  SELECT * FROM posts;
+SQL
+
+<<~SQL.squish
+  SELECT * FROM table
+    WHERE id = 1
+SQL
+
+execute(<<~SQL.squish, "Post Load")
+  SELECT * FROM posts
+    WHERE post_id = 1
+SQL
+----
+
+=== References
+
+* https://rails.rubystyle.guide/#squished-heredocs
+
 == Rails/TimeZone
 
 |===

lib/rubocop/cop/rails/squished_sql_heredocs.rb

@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Rails
+      #
+      # Checks SQL heredocs to use `.squish`.
+      #
+      # @example
+      #   # bad
+      #   <<-SQL
+      #     SELECT * FROM posts;
+      #   SQL
+      #
+      #   <<-SQL
+      #     SELECT * FROM posts
+      #       WHERE id = 1
+      #   SQL
+      #
+      #   execute(<<~SQL, "Post Load")
+      #     SELECT * FROM posts
+      #       WHERE post_id = 1
+      #   SQL
+      #
+      #   # good
+      #   <<-SQL.squish
+      #     SELECT * FROM posts;
+      #   SQL
+      #
+      #   <<~SQL.squish
+      #     SELECT * FROM table
+      #       WHERE id = 1
+      #   SQL
+      #
+      #   execute(<<~SQL.squish, "Post Load")
+      #     SELECT * FROM posts
+      #       WHERE post_id = 1
+      #   SQL
+      #
+      class SquishedSQLHeredocs < Cop
+        include Heredoc
+
+        SQL = 'SQL'
+        SQUISH = '.squish'
+        MSG = 'Use `%<expect>s` instead of `%<current>s`.'
+
+        def on_heredoc(node)
+          return unless offense_detected?(node)
+
+          add_offense(node)
+        end
+
+        def autocorrect(node)
+          lambda do |corrector|
+            corrector.insert_after(node, SQUISH)
+          end
+        end
+
+        private
+
+        def offense_detected?(node)
+          sql_heredoc?(node) && !using_squish?(node)
+        end
+
+        def sql_heredoc?(node)
+          delimiter_string(node) == SQL
+        end
+
+        def using_squish?(node)
+          node.parent&.send_type? && node.parent&.method?(:squish)
+        end
+
+        def message(node)
+          format(
+            MSG,
+            expect: "#{node.source}#{SQUISH}",
+            current: node.source
+          )
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/rails_cops.rb

@@ -77,6 +77,7 @@
 require_relative 'rails/scope_args'
 require_relative 'rails/short_i18n'
 require_relative 'rails/skips_model_validations'
+require_relative 'rails/squished_sql_heredocs'
 require_relative 'rails/time_zone'
 require_relative 'rails/uniq_before_pluck'
 require_relative 'rails/unique_validation_without_index'

spec/rubocop/cop/rails/squished_sql_heredocs_spec.rb

@@ -0,0 +1,86 @@
+# frozen_string_literal: true
+
+RSpec.describe RuboCop::Cop::Rails::SquishedSQLHeredocs, :config do
+  subject(:cop) { described_class.new(config) }
+
+  context 'with multi line heredoc' do
+    it 'registers an offense and corrects it' do
+      expect_offense(<<~RUBY)
+        <<~SQL
+        ^^^^^^ Use `<<~SQL.squish` instead of `<<~SQL`.
+          SELECT * FROM posts
+            WHERE id = 1
+        SQL
+      RUBY
+
+      expect_correction(<<~RUBY)
+        <<~SQL.squish
+          SELECT * FROM posts
+            WHERE id = 1
+        SQL
+      RUBY
+    end
+
+    it 'does not register an offense' do
+      expect_no_offenses(<<~RUBY)
+        <<-SQL.squish
+          SELECT * FROM posts
+            WHERE id = 1
+        SQL
+      RUBY
+    end
+  end
+
+  context 'with single line heredoc' do
+    it 'registers an offense and corrects it' do
+      expect_offense(<<~RUBY)
+        <<-SQL
+        ^^^^^^ Use `<<-SQL.squish` instead of `<<-SQL`.
+          SELECT * FROM posts;
+        SQL
+      RUBY
+
+      expect_correction(<<~RUBY)
+        <<-SQL.squish
+          SELECT * FROM posts;
+        SQL
+      RUBY
+    end
+
+    it 'does not register an offense' do
+      expect_no_offenses(<<~RUBY)
+        <<-SQL.squish
+          SELECT * FROM posts;
+        SQL
+      RUBY
+    end
+  end
+
+  context 'with heredocs as method parameters' do
+    it 'registers an offense and corrects it' do
+      expect_offense(<<~RUBY)
+        execute(<<~SQL, "Post Load")
+                ^^^^^^ Use `<<~SQL.squish` instead of `<<~SQL`.
+          SELECT * FROM posts
+            WHERE post_id = 1
+        SQL
+      RUBY
+
+      expect_correction(<<~RUBY)
+        execute(<<~SQL.squish, "Post Load")
+          SELECT * FROM posts
+            WHERE post_id = 1
+        SQL
+      RUBY
+    end
+
+    it 'does not register an offense' do
+      expect_no_offenses(<<~RUBY)
+        execute(<<~SQL.squish, "Post Load")
+          SELECT * FROM posts
+            WHERE post_id = 1
+        SQL
+      RUBY
+    end
+  end
+end