From 8fa11a844140a75abe530efec94c7c5e6874d485 Mon Sep 17 00:00:00 2001
From: Koichi ITO <koic.ito@gmail.com>
Date: Wed, 29 Jul 2020 04:02:16 +0900
Subject: [PATCH] [Fix #8406] Improve `Style/AccessorGrouping`'s
 auto-correction

## Summary

Fixes #8406.

This PR improves `Style/AccessorGrouping`'s auto-correction to remove
redundant blank lines.

## Other Information

This PR doesn't update to `Cop::Base` to make it clear the difference
between the changes. Will be updated with other `Style` cops in different PR.
---
 CHANGELOG.md                                     |  1 +
 lib/rubocop/cop/style/accessor_grouping.rb       | 16 +++++++++-------
 spec/rubocop/cop/style/accessor_grouping_spec.rb |  8 --------
 3 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8153795cece..cc6985421bf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,7 @@
 * [#8375](https://github.com/rubocop-hq/rubocop/pull/8375): Fix an infinite loop error for `Style/EmptyMethod`. ([@koic][])
 * [#8385](https://github.com/rubocop-hq/rubocop/pull/8385): Remove auto-correction for `Lint/EnsureReturn`. ([@marcandre][])
 * [#8391](https://github.com/rubocop-hq/rubocop/issues/8391): Mark `Style/ArrayCoercion` as not safe. ([@marcandre][])
+* [#8406](https://github.com/rubocop-hq/rubocop/issues/8406): Improve `Style/AccessorGrouping`'s auto-correction to remove redundant blank lines. ([@koic][])
 
 ### Changes
 
diff --git a/lib/rubocop/cop/style/accessor_grouping.rb b/lib/rubocop/cop/style/accessor_grouping.rb
index 25290de1841..bf5dbfd5580 100644
--- a/lib/rubocop/cop/style/accessor_grouping.rb
+++ b/lib/rubocop/cop/style/accessor_grouping.rb
@@ -33,6 +33,7 @@ module Style
       #
       class AccessorGrouping < Cop
         include ConfigurableEnforcedStyle
+        include RangeHelp
         include VisibilityHelp
 
         GROUPED_MSG = 'Group together all `%<accessor>s` attributes.'
@@ -52,7 +53,12 @@ def on_class(node)
 
         def autocorrect(node)
           lambda do |corrector|
-            corrector.replace(node, correction(node))
+            if (preferred_accessors = preferred_accessors(node))
+              corrector.replace(node, preferred_accessors)
+            else
+              range = range_with_surrounding_space(range: node.loc.expression, side: :left)
+              corrector.remove(range)
+            end
           end
         end
 
@@ -110,14 +116,10 @@ def message(send_node)
           format(msg, accessor: send_node.method_name)
         end
 
-        def correction(node)
+        def preferred_accessors(node)
           if grouped_style?
             accessors = sibling_accessors(node)
-            if node == accessors.first
-              group_accessors(node, accessors)
-            else
-              ''
-            end
+            group_accessors(node, accessors) if node == accessors.first
           else
             separate_accessors(node)
           end
diff --git a/spec/rubocop/cop/style/accessor_grouping_spec.rb b/spec/rubocop/cop/style/accessor_grouping_spec.rb
index 59d8b01a300..03c4772396e 100644
--- a/spec/rubocop/cop/style/accessor_grouping_spec.rb
+++ b/spec/rubocop/cop/style/accessor_grouping_spec.rb
@@ -25,9 +25,7 @@ class Foo
       expect_correction(<<~RUBY)
         class Foo
           attr_reader :bar1, :bar2, :bar3, :bar4
-          
           attr_accessor :quux
-          
           other_macro :zoo
         end
       RUBY
@@ -61,7 +59,6 @@ class Foo
       expect_correction(<<~RUBY)
         class Foo
           attr_reader :bar1, :bar2, :bar3
-          
 
           protected
           attr_accessor :quux
@@ -69,10 +66,8 @@ class Foo
           private
           attr_reader :baz1, :baz2, :baz4
           attr_writer :baz3
-          
 
           public
-          
           other_macro :zoo
         end
       RUBY
@@ -105,12 +100,10 @@ class Foo
 
           class << self
             attr_reader :baz1, :baz2, :baz3
-            
 
             private
 
             attr_reader :quux1, :quux2
-            
           end
         end
       RUBY
@@ -160,7 +153,6 @@ class Foo
           attr_reader :three
 
           attr_reader :four, :five
-          
         end
       RUBY
     end