[SUREFIRE-2232] [REGRESSION] StatelessXmlReporter fails to process failed result without a throwable

This closes #716

Author: dr29bart

maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/report/StatelessXmlReporter.java

@@ -47,6 +47,7 @@
 import static org.apache.maven.plugin.surefire.report.ReportEntryType.SKIPPED;
 import static org.apache.maven.plugin.surefire.report.ReportEntryType.SUCCESS;
 import static org.apache.maven.surefire.shared.utils.StringUtils.isBlank;
+import static org.apache.maven.surefire.shared.utils.StringUtils.isNotBlank;
 
 // CHECKSTYLE_OFF: LineLength
 /**
@@ -451,7 +452,9 @@ private static void getTestProblems(
                     String type = delimiter == -1 ? stackTrace : stackTrace.substring(0, delimiter);
                     ppw.addAttribute("type", type);
                 } else {
-                    ppw.addAttribute("type", new StringTokenizer(stackTrace).nextToken());
+                    if (isNotBlank(stackTrace)) {
+                        ppw.addAttribute("type", new StringTokenizer(stackTrace).nextToken());
+                    }
                 }
             }
         }

maven-surefire-common/src/test/java/org/apache/maven/plugin/surefire/report/StatelessXmlReporterTest.java

@@ -522,6 +522,23 @@ public void testSyncOnDeferredFile() throws Exception {
         assertThat((boolean) getInternalState(out, "closed")).isTrue();
     }
 
+    public void testReporterHandlesATestWithoutMessageAndWithEmptyStackTrace() {
+        StackTraceWriter stackTraceWriterOne = new DeserializedStacktraceWriter(null, null, "");
+
+        WrappedReportEntry testReport = new WrappedReportEntry(
+                new SimpleReportEntry(
+                        NORMAL_RUN, 1L, getClass().getName(), null, "a test name", null, stackTraceWriterOne, 5),
+                ERROR,
+                5,
+                null,
+                null);
+
+        StatelessXmlReporter reporter = new StatelessXmlReporter(
+                reportDir, null, false, 1, new HashMap<>(), XSD, "3.0.1", false, false, false, false);
+
+        reporter.testSetCompleted(testReport, stats);
+    }
+
     private boolean defaultCharsetSupportsSpecialChar() {
         // some charsets are not able to deal with \u0115 on both ways of the conversion
         return "\u0115\u00DC".equals(new String("\u0115\u00DC".getBytes()));