junit-team/junit5 · error · JUnitException

Failed to create XML events file

Error message

Failed to create XML events file

What it means

Thrown by OpenTestReportGeneratingListener.createDocumentWriter() (file-mode branch) as a JUnitException when Events.createDocumentWriter for open-test-report.xml under outputDir fails. Reached only when socket mode is not configured; the exception wraps the underlying I/O or XML failure.

Source

Thrown at junit-platform-reporting/src/main/java/org/junit/platform/reporting/open/xml/OpenTestReportGeneratingListener.java:167

			NamespaceRegistry namespaceRegistry) throws Exception {
		return config.get(SOCKET_PROPERTY_NAME, Integer::valueOf) //
				.map(port -> {
					try {
						Socket socket = new Socket(InetAddress.getLoopbackAddress(), port);
						Writer writer = new OutputStreamWriter(socket.getOutputStream(), StandardCharsets.UTF_8);
						return Events.createDocumentWriter(namespaceRegistry, writer);
					}
					catch (Exception e) {
						throw new JUnitException("Failed to connect to socket on port " + port, e);
					}
				}) //
				.orElseGet(() -> {
					try {
						Path eventsXml = requireNonNull(outputDir).resolve("open-test-report.xml");
						return Events.createDocumentWriter(namespaceRegistry, eventsXml);
					}
					catch (Exception e) {
						throw new JUnitException("Failed to create XML events file", e);
					}
				});
	}

	private boolean isEnabled(ConfigurationParameters config) {
		return config.getBoolean(ENABLED_PROPERTY_NAME).orElse(false);
	}

	private boolean isGitEnabled(ConfigurationParameters config) {
		return config.getBoolean(GIT_ENABLED_PROPERTY_NAME).orElse(false);
	}

	@SuppressWarnings("EmptyCatch")
	private void reportInfrastructure(ConfigurationParameters config) {
		eventsFileWriter.append(infrastructure(), infrastructure -> {
			try {
				String hostName = InetAddress.getLocalHost().getHostName();
				infrastructure.append(hostName(hostName));

View on GitHub (pinned to 956246301e)

Solutions

1. Set junit.platform.output.dir to a writable, unique directory.
2. Ensure the output directory persists for the whole test run (do not clean it mid-run).
3. Inspect getCause() for the precise I/O error.
4. If reporting is optional, set junit.platform.reporting.open.xml.enabled=false.

Example fix

# before
junit.platform.reporting.open.xml.enabled = true
# output dir read-only -> JUnitException

# after
junit.platform.reporting.open.xml.enabled = true
junit.platform.output.dir = target/test-reports-${random.uuid}

Path out = testPlan.getOutputDirectoryCreator().getRootDirectory();
Files.createDirectories(out);
if (!Files.isWritable(out)) throw new IllegalStateException("output dir not writable: " + out);

static boolean canWriteEventsFile(Path dir) {
    Path f = dir.resolve("open-test-report.xml");
    try { Files.createDirectories(dir); return Files.isWritable(dir); }
    catch (IOException e) { return false; }
}

try {
    Events.createDocumentWriter(ns, outputDir.resolve("open-test-report.xml"));
} catch (Exception e) {
    // fall back to a temp dir, or disable reporting
}

When it happens

Trigger: XML reporting enabled, no socket property set, and outputDir (from the TestPlan's OutputDirectoryCreator, rooted at OutputDir) cannot host open-test-report.xml - e.g. directory missing, read-only, or the XML writer cannot initialise the file.

Common situations: Output directory deleted or made read-only between discovery and execution. Disk full. Concurrent test runs colliding on the same non-unique output dir. Misconfigured junit.platform.output.dir.

Related errors

• Failed to close XML events file
• Could not open color palette properties file
• Failed to retrieve canonical path for file: ${file}
• Failed to retrieve canonical path for directory: ${directory
• Failed to retrieve canonical path for directory: ${directory

AI-assisted analysis of junit-team/junit5@956246301e (2026-08-04). Data as JSON: /data/errors/55c2760bc913d776.json. Report an issue: GitHub.