From 3b7793d4558f457532e6b47b8043e1181905d89d Mon Sep 17 00:00:00 2001
From: Dmytro Savochkin <dmytro.savochkin@techmagic.co>
Date: Mon, 24 Aug 2020 16:47:20 +0300
Subject: [PATCH] [Fix #8576] Fix `Style/IfUnlessModifier` to ignore cop
 disable comment directives when considering conversion to modifier form

---
 CHANGELOG.md                                |  1 +
 lib/rubocop/cop/mixin/statement_modifier.rb | 12 +++++++++---
 lib/rubocop/cop/style/if_unless_modifier.rb |  4 ----
 spec/rubocop/cli/cli_autocorrect_spec.rb    | 21 +++++++++++++++++++++
 4 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4f11ffba641f..2ce12502fa2d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -43,6 +43,7 @@
 * [#8481](https://github.com/rubocop-hq/rubocop/pull/8481): Fix autocorrect for elements with newlines in `Style/SymbolArray` and `Style/WordArray`. ([@biinari][])
 * [#8475](https://github.com/rubocop-hq/rubocop/issues/8475): Fix a false positive for `Style/HashAsLastArrayItem` when there are duplicate hashes in the array. ([@wcmonty][])
 * [#8497](https://github.com/rubocop-hq/rubocop/issues/8497): Fix `Style/IfUnlessModifier` to add parentheses when converting if-end condition inside a parenthesized method argument list. ([@dsavochkin][])
+* [#8576](https://github.com/rubocop-hq/rubocop/issues/8576): Fix `Style/IfUnlessModifier` to ignore cop disable comment directives when considering conversion to the modifier form. ([@dsavochkin][])
 
 ### Changes
 
diff --git a/lib/rubocop/cop/mixin/statement_modifier.rb b/lib/rubocop/cop/mixin/statement_modifier.rb
index 4fe2be136e36..4aae0e9f3554 100644
--- a/lib/rubocop/cop/mixin/statement_modifier.rb
+++ b/lib/rubocop/cop/mixin/statement_modifier.rb
@@ -57,10 +57,11 @@ def to_modifier_form(node)
       end
 
       def first_line_comment(node)
-        comment =
-          processed_source.find_comment { |c| c.loc.line == node.loc.line }
+        comment = processed_source.find_comment { |c| c.loc.line == node.loc.line }
+        return unless comment
 
-        comment ? comment.loc.expression.source : nil
+        comment_source = comment.loc.expression.source
+        comment_source unless comment_disables_cop?(comment_source)
       end
 
       def parenthesize?(node)
@@ -80,6 +81,11 @@ def max_line_length
 
         config.for_cop('Layout/LineLength')['Max']
       end
+
+      def comment_disables_cop?(comment)
+        regexp_pattern = "# rubocop : (disable|todo) ([^,],)* (all|#{cop_name})"
+        Regexp.new(regexp_pattern.gsub(' ', '\s*')).match?(comment)
+      end
     end
   end
 end
diff --git a/lib/rubocop/cop/style/if_unless_modifier.rb b/lib/rubocop/cop/style/if_unless_modifier.rb
index 53d3a36f3b41..b73663662460 100644
--- a/lib/rubocop/cop/style/if_unless_modifier.rb
+++ b/lib/rubocop/cop/style/if_unless_modifier.rb
@@ -157,10 +157,6 @@ def to_normal_form(node)
             #{indentation}end
           RUBY
         end
-
-        def first_line_comment(node)
-          processed_source.comment_at_line(node.loc.line)&.text
-        end
       end
     end
   end
diff --git a/spec/rubocop/cli/cli_autocorrect_spec.rb b/spec/rubocop/cli/cli_autocorrect_spec.rb
index 88cca7b65728..15f455db9cb9 100644
--- a/spec/rubocop/cli/cli_autocorrect_spec.rb
+++ b/spec/rubocop/cli/cli_autocorrect_spec.rb
@@ -1607,4 +1607,25 @@ def self.some_method(foo, bar: 1)
     RUBY
     expect(source_file.read).to eq(corrected)
   end
+
+  it 'does not correct Style/IfUnlessModifier offense disabled by a comment directive and ' \
+     'does not fire Lint/RedundantCopDisableDirective offense even though that directive ' \
+     'would make the modifier form too long' do
+    create_file('.rubocop.yml', <<~YAML)
+      Style/FrozenStringLiteralComment:
+        Enabled: false
+    YAML
+
+    source_file = Pathname('example.rb')
+    source = <<~RUBY
+      if i > 1 # rubocop:disable Style/IfUnlessModifier
+        raise '_______________________________________________________________________'
+      end
+    RUBY
+    create_file(source_file, source)
+
+    status = cli.run(['--auto-correct-all'])
+    expect(status).to eq(0)
+    expect(source_file.read).to eq(source)
+  end
 end