From 8fd210a5b11fda9506c01e155e595c90ba3e296e Mon Sep 17 00:00:00 2001
From: Koichi ITO <koic.ito@gmail.com>
Date: Sat, 2 May 2020 00:31:51 +0900
Subject: [PATCH] Support autocorrection for `Layout/ConditionPosition`

This PR supports autocorrection for `Layout/ConditionPosition`.
---
 CHANGELOG.md                                    |  1 +
 config/default.yml                              |  1 +
 lib/rubocop/cop/layout/condition_position.rb    | 14 ++++++++++++--
 manual/cops_layout.md                           |  2 +-
 .../cop/layout/condition_position_spec.rb       | 17 +++++++++++++++--
 5 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 54df5bcf232..07ef2ff04e2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@
 * [#7937](https://github.com/rubocop-hq/rubocop/pull/7937): Support autocorrection for `Style/IfWithSemicolon`. ([@koic][])
 * [#3696](https://github.com/rubocop-hq/rubocop/issues/3696): Add `AllowComments` option to `Lint/EmptyWhen` cop. ([@koic][])
 * [#7910](https://github.com/rubocop-hq/rubocop/pull/7910): Support autocorrection for `Lint/ParenthesesAsGroupedExpression`. ([@koic][])
+* [#7925](https://github.com/rubocop-hq/rubocop/pull/7925): Support autocorrection for `Layout/ConditionPosition`. ([@koic][])
 
 ### Bug fixes
 
diff --git a/config/default.yml b/config/default.yml
index 510d43a67e4..dc73d7fc4b8 100644
--- a/config/default.yml
+++ b/config/default.yml
@@ -376,6 +376,7 @@ Layout/ConditionPosition:
   StyleGuide: '#same-line-condition'
   Enabled: true
   VersionAdded: '0.53'
+  VersionChanged: '0.83'
 
 Layout/DefEndAlignment:
   Description: 'Align ends corresponding to defs correctly.'
diff --git a/lib/rubocop/cop/layout/condition_position.rb b/lib/rubocop/cop/layout/condition_position.rb
index c977ae65f96..29f17db3f99 100644
--- a/lib/rubocop/cop/layout/condition_position.rb
+++ b/lib/rubocop/cop/layout/condition_position.rb
@@ -23,6 +23,8 @@ module Layout
       #     do_something
       #   end
       class ConditionPosition < Cop
+        include RangeHelp
+
         MSG = 'Place the condition on the same line as `%<keyword>s`.'
 
         def on_if(node)
@@ -34,9 +36,17 @@ def on_if(node)
         def on_while(node)
           check(node)
         end
+        alias on_until on_while
 
-        def on_until(node)
-          check(node)
+        def autocorrect(node)
+          lambda do |corrector|
+            range = range_by_whole_lines(
+              node.source_range, include_final_newline: true
+            )
+
+            corrector.insert_after(node.parent.loc.keyword, " #{node.source}")
+            corrector.remove(range)
+          end
         end
 
         private
diff --git a/manual/cops_layout.md b/manual/cops_layout.md
index cbe4e33e2d1..1cd976e9397 100644
--- a/manual/cops_layout.md
+++ b/manual/cops_layout.md
@@ -713,7 +713,7 @@ end
 
 Enabled by default | Safe | Supports autocorrection | VersionAdded | VersionChanged
 --- | --- | --- | --- | ---
-Enabled | Yes | No | 0.53 | -
+Enabled | Yes | Yes  | 0.53 | 0.83
 
 This cop checks for conditions that are not on the same line as
 if/while/until.
diff --git a/spec/rubocop/cop/layout/condition_position_spec.rb b/spec/rubocop/cop/layout/condition_position_spec.rb
index 17dba5551f4..e3e2071cf30 100644
--- a/spec/rubocop/cop/layout/condition_position_spec.rb
+++ b/spec/rubocop/cop/layout/condition_position_spec.rb
@@ -4,13 +4,18 @@
   subject(:cop) { described_class.new }
 
   %w[if unless while until].each do |keyword|
-    it 'registers an offense for condition on the next line' do
+    it 'registers an offense and corrects for condition on the next line' do
       expect_offense(<<~RUBY)
         #{keyword}
         x == 10
         ^^^^^^^ Place the condition on the same line as `#{keyword}`.
         end
       RUBY
+
+      expect_correction(<<~RUBY)
+        #{keyword} x == 10
+        end
+      RUBY
     end
 
     it 'accepts condition on the same line' do
@@ -29,7 +34,7 @@
     end
   end
 
-  it 'registers an offense for elsif condition on the next line' do
+  it 'registers an offense and corrects for elsif condition on the next line' do
     expect_offense(<<~RUBY)
       if something
         test
@@ -39,6 +44,14 @@
         test
       end
     RUBY
+
+    expect_correction(<<~RUBY)
+      if something
+        test
+      elsif something
+        test
+      end
+    RUBY
   end
 
   it 'handles ternary ops' do