Fix #18 - crashing when removing directories with nested paths

lib/listen/directory_record.rb

@@ -169,6 +169,9 @@ def detect_modifications_and_removals(directory, options = {})
     # @option options [Boolean] relative_paths whether or not to use relative paths for changes
     #
     def detect_additions(directory, options = {})
+      # Don't process removed directories
+      return unless File.exist?(directory)
+
       Find.find(directory) do |path|
         next if path == @directory
 

spec/listen/directory_record_spec.rb

@@ -747,6 +747,23 @@
           @record.paths["#{path}/a_directory"]['file.rb'].should be_nil
         end
       end
+
+      context 'with nested paths' do
+        it 'detects removals without crashing - #18', :focus do
+          fixtures do |path|
+            mkdir_p 'a_directory/b_directory'
+            touch 'a_directory/b_directory/do_not_use.rb'
+
+            modified, added, removed = changes(path, :paths => [path, "#{path}/a_directory", "#{path}/b_directory"]) do
+              rm_r 'a_directory'
+            end
+
+            added.should be_empty
+            modified.should be_empty
+            removed.should =~ %w(a_directory/b_directory/do_not_use.rb)
+          end
+        end
+      end
     end
 
     context 'with a path outside the directory for which a record is made' do