Make the JUnit formatter handle empty scenarios. Fixes #774.

Previously the JUnit formatter threw a NPE if a scenario had no steps.

Author: brasmusson

core/src/main/java/cucumber/runtime/formatter/JUnitFormatter.java

@@ -124,7 +124,9 @@ public void startOfScenarioLifeCycle(Scenario scenario) {
 
     @Override
     public void endOfScenarioLifeCycle(Scenario scenario) {
-        // NoOp
+        if (testCase != null && testCase.steps.isEmpty()) {
+            testCase.handleEmptyTestCase(doc, root);
+        }
     }
 
     private void addDummyTestCase() {
@@ -140,7 +142,6 @@ private void addDummyTestCase() {
     @Override
     public void result(Result result) {
         testCase.results.add(result);
-
         testCase.updateElement(doc, root);
     }
 
@@ -314,6 +315,15 @@ public void updateElement(Document doc, Element tc) {
             }
         }
 
+        public void handleEmptyTestCase(Document doc, Element tc) {
+            tc.setAttribute("time", calculateTotalDurationString());
+
+            String resultType = treatSkippedAsFailure ? "failure" : "skipped";
+            Element child = createElementWithMessage(doc, new StringBuilder(), resultType, "The scenario has no steps");
+
+            tc.appendChild(child);
+        }
+
         private String calculateTotalDurationString() {
             long totalDurationNanos = 0;
             for (Result r : results) {

core/src/test/java/cucumber/runtime/formatter/JUnitFormatterTest.java

@@ -525,12 +525,29 @@ public void should_handle_one_step_at_the_time_execution() throws Exception {
         assertXmlEqual(expected, actual);
     }
 
+    @Test
+    public void should_handle_empty_scenarios() throws Throwable {
+        CucumberFeature feature = TestHelper.feature("path/test.feature",
+                "Feature: feature name\n" +
+                        "  Scenario: scenario name\n");
+
+        String formatterOutput = runFeatureWithJUnitFormatter(feature);
+
+        String expected = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n" +
+                "<testsuite failures=\"0\" name=\"cucumber.runtime.formatter.JUnitFormatter\" skipped=\"1\" tests=\"1\" time=\"0\">\n" +
+                "    <testcase classname=\"feature name\" name=\"scenario name\" time=\"0\">\n" +
+                "        <skipped message=\"The scenario has no steps\" />\n" +
+                "    </testcase>\n" +
+                "</testsuite>\n";
+        assertXmlEqual(expected, formatterOutput);
+    }
+
     @Test
     public void should_add_dummy_testcase_if_no_scenarios_are_run_to_aviod_failed_jenkins_jobs() throws Throwable {
         CucumberFeature feature = TestHelper.feature("path/test.feature",
                 "Feature: feature name\n");
 
-        String formatterOutput = runFeatureWithJUnitFormatter(feature, Collections.<String, String>emptyMap(), Collections.<SimpleEntry<String, String>>emptyList(), milliSeconds(1));
+        String formatterOutput = runFeatureWithJUnitFormatter(feature);
 
         String expected = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n" +
                 "<testsuite failures=\"0\" name=\"cucumber.runtime.formatter.JUnitFormatter\" skipped=\"0\" time=\"0\">\n" +
@@ -566,6 +583,10 @@ private File runFeaturesWithJunitFormatter(final List<String> featurePaths, bool
         return report;
     }
 
+    private String runFeatureWithJUnitFormatter(final CucumberFeature feature) throws Throwable {
+        return runFeatureWithJUnitFormatter(feature, new HashMap<String, String>(), 0L);
+    }
+
     private String runFeatureWithJUnitFormatter(final CucumberFeature feature, final Map<String, String> stepsToResult, final long stepHookDuration)
             throws Throwable {
         return runFeatureWithJUnitFormatter(feature, stepsToResult, Collections.<SimpleEntry<String, String>>emptyList(), stepHookDuration);