Fix Style/EmptyCaseCondition's autocorrect.

Avoids incorrect use of `comments_before_line`.
The autocorrection worked only for case statements that were root of the document and were not indented
Also fix `Style/SafeNavigation`'s auto-correction, typical off-by-one error without a spec

lib/rubocop/cop/style/empty_case_condition.rb

@@ -73,7 +73,7 @@ def correct_case_when(corrector, case_node, when_nodes)
 
           corrector.replace(case_range, 'if')
 
-          keep_first_when_comment(case_node, when_nodes.first, corrector)
+          keep_first_when_comment(case_range, corrector)
 
           when_nodes[1..-1].each do |when_node|
             corrector.replace(when_node.loc.keyword, 'elsif')
@@ -93,15 +93,14 @@ def correct_when_conditions(corrector, when_nodes)
           end
         end
 
-        def keep_first_when_comment(case_node, first_when_node, corrector)
-          comment = processed_source.comments_before_line(
-            first_when_node.loc.keyword.line
-          ).map(&:text).join("\n")
+        def keep_first_when_comment(case_range, corrector)
+          indent = ' ' * case_range.column
+          comments = processed_source.each_comment_in_lines(
+            case_range.first_line...case_range.last_line
+          ).map { |comment| "#{indent}#{comment.text}\n" }.join
 
-          line = range_by_whole_lines(case_node.source_range)
-
-          corrector.insert_before(line, "#{comment}\n") if !comment.empty? &&
-                                                           !case_node.parent
+          line_beginning = case_range.adjust(begin_pos: -case_range.column)
+          corrector.insert_before(line_beginning, comments)
         end
       end
     end

spec/rubocop/cop/style/empty_case_condition_spec.rb

@@ -49,33 +49,40 @@
     context 'with multiple when branches and an `else` with code comments' do
       let(:source) do
         <<~RUBY
-          case
-          ^^^^ Do not use empty `case` condition, instead use an `if` expression.
-          # condition a
-          # This is a multi-line comment
-          when 1 == 2
-            foo
-          # condition b
-          when 1 == 1
-            bar
-          # condition c
-          else
-            baz
+          def example
+            # Comment before everything
+            case # first comment
+            ^^^^ Do not use empty `case` condition, instead use an `if` expression.
+            # condition a
+            # This is a multi-line comment
+            when 1 == 2
+              foo
+            # condition b
+            when 1 == 1
+              bar
+            # condition c
+            else
+              baz
+            end
           end
         RUBY
       end
       let(:corrected_source) do
         <<~RUBY
-          # condition a
-          # This is a multi-line comment
-          if 1 == 2
-            foo
-          # condition b
-          elsif 1 == 1
-            bar
-          # condition c
-          else
-            baz
+          def example
+            # Comment before everything
+            # first comment
+            # condition a
+            # This is a multi-line comment
+            if 1 == 2
+              foo
+            # condition b
+            elsif 1 == 1
+              bar
+            # condition c
+            else
+              baz
+            end
           end
         RUBY
       end