fix crash on cucumber 2.0

lib/guard/cucumber/notification_formatter.rb

@@ -41,10 +41,15 @@ def initialize(step_mother, _path_or_io, options)
         @options = options
         @file_names = []
         @step_mother = step_mother
+        @feature = nil
       end
 
-      def before_background(background)
-        @feature_name = background.feature.name
+      def before_background(_background)
+        # NOTE: background.feature is nil on newer gherkin versions
+      end
+
+      def before_feature(feature)
+        @feature = feature
       end
 
       # Notification after all features have completed.
@@ -62,7 +67,8 @@ def after_features(_features)
       #
       def before_feature_element(feature_element)
         @rerun = false
-        @feature_name = feature_element.name
+        # TODO: show feature element name instead?
+        # @feature = feature_element.name
       end
 
       # After a feature gets run.
@@ -89,11 +95,10 @@ def after_feature_element(feature_element)
       def step_name(_keyword, step_match, status, _src_indent, _bckgnd, _loc)
         return unless [:failed, :pending, :undefined].index(status)
 
-        # TODO: NO COVERAGE HERE!
         @rerun = true
         step_name = step_match.format_args(lambda { |param| "*#{ param }*" })
 
-        options = { title: @feature_name, image: icon_for(status) }
+        options = { title: @feature.name, image: icon_for(status) }
         Guard::Compat::UI.notify(step_name, options)
       end
 

spec/guard/cucumber/notification_formatter_spec.rb

@@ -25,19 +25,31 @@
   end
 
   describe "#step_name" do
+    let(:step_match) { instance_double(Cucumber::StepMatch) }
+    let(:feature) { instance_double(Cucumber::Ast::Feature, name: "feature1") }
+
+    before do
+      subject.before_feature(feature)
+      subject.before_background(background)
+      allow(step_match).to receive(:format_args) do |block|
+        block.call "step_name1"
+      end
+    end
+
     context "when failure is in a background step" do
-      let(:step_match) { instance_double(Cucumber::StepMatch) }
-      let(:feature) { instance_double(Cucumber::Ast::Feature, name: "feature1") }
       let(:background) { instance_double(Cucumber::Ast::Background, feature: feature) }
 
-      before do
-        subject.before_background(background)
-        allow(step_match).to receive(:format_args) do |block|
-          block.call "step_name1"
-        end
+      it "notifies with a valid feature name" do
+        expect(Guard::Compat::UI).to receive(:notify).with("*step_name1*", hash_including(title: "feature1"))
+        subject.step_name(nil, step_match, :failed, nil, nil, nil)
       end
+    end
 
-      it "notifies with a valid feature name" do
+    # workaround for: https://github.com/cucumber/gherkin/issues/334
+    context "with a buggy Background implementation" do
+      let(:background) { instance_double(Cucumber::Ast::Background, feature: nil) }
+
+      it "correctly gets the feature name" do
         expect(Guard::Compat::UI).to receive(:notify).with("*step_name1*", hash_including(title: "feature1"))
         subject.step_name(nil, step_match, :failed, nil, nil, nil)
       end