update PatchCop to support spanning errors

lib/pronto/rubocop/patch_cop.rb

@@ -14,10 +14,15 @@ def messages
         return [] unless valid?
 
         offenses.flat_map do |offense|
-          patch
+          offending_line = patch
             .added_lines
-            .select { |line| line.new_lineno == offense.line }
-            .map { |line| OffenseLine.new(self, offense, line).message }
+            .detect { |line| offense_includes?(offense, line.new_lineno) }
+
+          if offending_line
+            [OffenseLine.new(self, offense, offending_line).message]
+          else
+            []
+          end
         end
       end
 
@@ -67,6 +72,11 @@ def offenses
           .reject(&:disabled?)
       end
 
+      def offense_includes?(offense, line_number)
+        offense_range = (offense.location.first_line..offense.location.last_line)
+        offense_range.include?(line_number)
+      end
+
       def team
         @team ||=
           if ::RuboCop::Cop::Team.respond_to?(:mobilize)

spec/pronto/rubocop/patch_cop_spec.rb

@@ -12,7 +12,8 @@
   let(:ast) { double :ast, each_node: nil }
   let(:processed_source) { double :processed_source, ast: ast }
   let(:team) { double :team, inspect_file: [offense] }
-  let(:offense) { double :offense, disabled?: false, line: 42 }
+  let(:offense_location) { double :location, first_line: 42, last_line: 43 }
+  let(:offense) { double :offense, disabled?: false, location: offense_location }
   let(:offense_line) { double :offense_line, message: 'Err' }
 
   before do
@@ -31,5 +32,13 @@
     it do
       expect(patch_cop.messages).to eq(['Err'])
     end
+
+    context 'when there is an error including the patch, but not starting inside it' do
+      let(:offense_location) { double :location, first_line: 40, last_line: 43 }
+
+      it do
+        expect(patch_cop.messages).to eq(['Err'])
+      end
+    end
   end
 end