Add autocorrect for Lint/EmptyEnsure cop

CHANGELOG.md

@@ -11,6 +11,7 @@
 * [#3984](https://github.com/bbatsov/rubocop/pull/3984): Add new `Style/EmptyLinesAroundBeginBody` cop. ([@pocke][])
 * [#3995](https://github.com/bbatsov/rubocop/pull/3995): Add new `Style/EmptyLinesAroundExceptionHandlingKeywords` cop. ([@pocke][])
 * [#4019](https://github.com/bbatsov/rubocop/pull/4019): Make configurable `Style/MultilineMemoization` cop. ([@pocke][])
+* [#4018](https://github.com/bbatsov/rubocop/pull/4018): Add autocorrect `Lint/EmptyEnsure` cop. ([@pocke][])
 
 ### Changes
 

config/enabled.yml

@@ -1108,6 +1108,7 @@ Lint/ElseLayout:
 Lint/EmptyEnsure:
   Description: 'Checks for empty ensure block.'
   Enabled: true
+  AutoCorrect: false
 
 Lint/EmptyExpression:
   Description: 'Checks for empty expressions.'

lib/rubocop/cop/lint/empty_ensure.rb

@@ -50,6 +50,12 @@ def on_ensure(node)
 
           add_offense(node, :keyword) unless ensure_body
         end
+
+        def autocorrect(node)
+          lambda do |corrector|
+            corrector.remove(node.loc.keyword)
+          end
+        end
       end
     end
   end

manual/cops_lint.md

@@ -498,7 +498,7 @@ end
 
 Enabled by default | Supports autocorrection
 --- | ---
-Enabled | No
+Enabled | Yes
 
 This cop checks for empty `ensure` blocks
 
@@ -539,6 +539,13 @@ ensure
 end
 ```
 
+### Important attributes
+
+Attribute | Value
+--- | ---
+AutoCorrect | false
+
+
 ## Lint/EmptyExpression
 
 Enabled by default | Supports autocorrection

spec/rubocop/cop/lint/empty_ensure_spec.rb

@@ -14,6 +14,20 @@
     expect(cop.offenses.size).to eq(1)
   end
 
+  it 'autocorrects for empty ensure' do
+    corrected = autocorrect_source(cop,
+                                   ['begin',
+                                    '  something',
+                                    'ensure',
+                                    'end'])
+    expect(corrected).to eq([
+      'begin',
+      '  something',
+      '',
+      'end'
+    ].join("\n"))
+  end
+
   it 'does not register an offense for non-empty ensure' do
     inspect_source(cop,
                    ['begin',