Merge pull request #2382 from jonas054/2003_unneeded_disable_better_s…

…olution

[Fix #2003] Handle --auto-correct in Lint/UnneededDisable

CHANGELOG.md

@@ -59,6 +59,7 @@
 * [#2321](https://github.com/bbatsov/rubocop/issues/2321): In `Style/EachWithObject`, don't replace reduce with each_with_object if the accumulator parameter is assigned to in the block. ([@alexdowad][])
 * [#1981](https://github.com/bbatsov/rubocop/issues/1981): `Lint/UselessAssignment` doesn't erroneously identify assignments in identical if branches as useless. ([@alexdowad][])
 * [#2323](https://github.com/bbatsov/rubocop/issues/2323): `Style/IfUnlessModifier` cop parenthesizes autocorrected code when necessary due to operator precedence, to avoid changing its meaning. ([@alexdowad][])
+* [#2003](https://github.com/bbatsov/rubocop/issues/2003): Make `Lint/UnneededDisable` work with `--auto-correct`. ([@jonas054][])
 
 ## 0.34.2 (21/09/2015)
 

lib/rubocop/runner.rb

@@ -83,9 +83,15 @@ def process_file(file)
         file_started(file, disabled_line_ranges, comments)
       else
         processed_source = get_processed_source(file)
-        file_started(file, processed_source.disabled_line_ranges,
-                     processed_source.comments)
-        offenses = do_inspection_loop(file, processed_source)
+        # Use delegators for objects sent to the formatters. These can be
+        # updated when the file is re-inspected.
+        disabled_line_ranges =
+          SimpleDelegator.new(processed_source.disabled_line_ranges)
+        comments = SimpleDelegator.new(processed_source.comments)
+
+        file_started(file, disabled_line_ranges, comments)
+        offenses = do_inspection_loop(file, processed_source,
+                                      disabled_line_ranges, comments)
         save_in_cache(cache, offenses, processed_source)
       end
 
@@ -129,7 +135,8 @@ def save_in_cache(cache, offenses, processed_source)
                  processed_source.comments)
     end
 
-    def do_inspection_loop(file, processed_source)
+    def do_inspection_loop(file, processed_source, disabled_line_ranges,
+                           comments)
       offenses = []
 
       # Keep track of the state of the source. If a cop modifies the source
@@ -156,6 +163,10 @@ def do_inspection_loop(file, processed_source)
         break unless updated_source_file
 
         processed_source = get_processed_source(file)
+
+        # Update delegators with new objects.
+        disabled_line_ranges.__setobj__(processed_source.disabled_line_ranges)
+        comments.__setobj__(processed_source.comments)
       end
 
       offenses

spec/rubocop/cli_spec.rb

@@ -2374,6 +2374,26 @@ def interrupt
                 ''].join("\n"))
     end
 
+    context 'when --auto-correct is given' do
+      it 'does not trigger UnneededDisable due to lines moving around' do
+        src = ['a = 1 # rubocop:disable Lint/UselessAssignment']
+        create_file('example.rb', src)
+        create_file('.rubocop.yml', ['Style/Encoding:',
+                                     '  Enabled: true'])
+        expect(cli.run(['--format', 'offenses', '-a', 'example.rb'])).to eq(0)
+        expect($stdout.string).to eq(['',
+                                      '1  Style/Encoding',
+                                      '--',
+                                      '1  Total',
+                                      '',
+                                      ''].join("\n"))
+        expect(IO.read('example.rb'))
+          .to eq(['# encoding: utf-8',
+                  'a = 1 # rubocop:disable Lint/UselessAssignment',
+                  ''].join("\n"))
+      end
+    end
+
     it 'can disable selected cops in a code section' do
       create_file('example.rb',
                   ['# encoding: utf-8',