quarkusio/quarkus · error · IllegalStateException

Tests already in progress

Error message

Tests already in progress

What it means

ModuleTestRunner.prepare throws IllegalStateException 'Tests already in progress' when a test run is requested while a previous runner instance is still active in the same synchronized block. Quarkus dev mode allows only one continuous-testing run at a time per module.

Source

Thrown at core/deployment/src/main/java/io/quarkus/deployment/dev/testing/ModuleTestRunner.java:66

                log.debug("Exception while aborting runner during reset", e);
            }
            runner = null;
        }
    }

    Runnable prepare(ClassScanResult classScanResult, boolean reRunFailures, long runId, TestRunListener listener) {
        return prepare(classScanResult, reRunFailures, runId, listener, null);
    }

    Runnable prepare(ClassScanResult classScanResult, boolean reRunFailures, long runId, TestRunListener listener,
            String specificSelection) {

        var old = Thread.currentThread().getContextClassLoader();
        Thread.currentThread().setContextClassLoader(testApplication.getOrCreateAugmentClassLoader());
        try {
            synchronized (this) {
                if (runner != null) {
                    throw new IllegalStateException("Tests already in progress");
                }
                JunitTestRunner.Builder builder = new JunitTestRunner.Builder()
                        .setClassScanResult(classScanResult)
                        .setRunId(runId)
                        .setTestState(testState)
                        .setTestClassUsages(testClassUsages)
                        .setTestApplication(testApplication)
                        .setIncludeTags(testSupport.includeTags)
                        .setExcludeTags(testSupport.excludeTags)
                        .setInclude(testSupport.include)
                        .setExclude(testSupport.exclude)
                        .setSpecificSelection(specificSelection != null ? specificSelection : testSupport.specificSelection)
                        .setIncludeEngines(testSupport.includeEngines)
                        .setExcludeEngines(testSupport.excludeEngines)
                        .setTestType(testSupport.testType)
                        .setModuleInfo(moduleInfo)
                        .addListener(listener)
                        .setFailingTestsOnly(classScanResult != null && testSupport.brokenOnlyMode); //broken only mode is only when changes are made, not for forced runs

View on GitHub (pinned to e1c734241f)

Solutions

1. Wait for the current test run to finish before triggering another; avoid rapid re-saves
2. Stop and restart quarkus:dev if a previous run appears stuck
3. Ensure only one client (IDE or terminal) drives continuous testing
4. Report if reproducible — a run that never clears 'runner' indicates a lifecycle bug in the test runner

Example fix

// before: test paused at breakpoint, retriggers pile up
// after: resume/stop the paused run, or disable continuous testing
mvn quarkus:dev -Dquarkus.test.continuous-testing=disabled

if (runnerActive) {
    throw new IllegalStateException("Skip trigger: a test run is already in progress");
} // or simply wait for the completed future before calling prepare again

static boolean canStartRun(ModuleTestRunner r) {
    synchronized (r) { return r.hasActiveRunner(); } // expose/track an active flag before prepare()
}

try {
    testRunner.prepare(ctx, runId);
} catch (IllegalStateException e) {
    if ("Tests already in progress".equals(e.getMessage())) {
        // debounce: skip this trigger and let the current run finish
        return;
    }
    throw e;
}

When it happens

Trigger: Calling prepare() when the field 'runner' is non-null — i.e. a prior JUnit test run has not completed or was never marked finished, and another run (e.g. triggered by file change + test trigger) arrives concurrently.

Common situations: Continuous testing retriggered rapidly (save storms, all-files trigger) overlapping a slow previous run; paused/deadlocked test holding the runner; IDE and CLI both driving continuous testing.

Related errors

• Failed to create compiler
• The application is stopping
• className parameter is required
• Should be virtual server channel:
• A test method annotated with @TestReactiveTransaction must a

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/b348436657cabfeb. Report an issue: GitHub.