What causes "Unable to invoke 'GetRunnerPath'." in dotnet/BenchmarkDotNet?

Delete the cached prerequisite directory and re-run InitAsync to re-download and extract cleanly.

dotnet/BenchmarkDotNet · error · InvalidOperationException

Unable to invoke 'GetRunnerPath'.

Error message

Unable to invoke 'GetRunnerPath'.

What it means

GetRunnerPath's final guard for dotTrace: GetRunnerPath was found and invoked but returned null / not castable to string. The method exists but produced no usable runner path, usually because the prerequisite runner binary was never extracted.

Source

Thrown at src/BenchmarkDotNet.Diagnostics.dotTrace/DotTraceDiagnoser.cs:68

    protected override string GetRunnerPath()
    {
        var consoleRunnerPackageField = typeof(DotTrace).GetField("ConsoleRunnerPackage", BindingFlags.NonPublic | BindingFlags.Static);
        if (consoleRunnerPackageField == null)
            throw new InvalidOperationException("Field 'ConsoleRunnerPackage' not found.");

        object? consoleRunnerPackage = consoleRunnerPackageField.GetValue(null);
        if (consoleRunnerPackage == null)
            throw new InvalidOperationException("Unable to get value of 'ConsoleRunnerPackage'.");

        var consoleRunnerPackageType = consoleRunnerPackage.GetType();
        var getRunnerPathMethod = consoleRunnerPackageType.GetMethod("GetRunnerPath");
        if (getRunnerPathMethod == null)
            throw new InvalidOperationException("Method 'GetRunnerPath' not found.");

        string? runnerPath = getRunnerPathMethod.Invoke(consoleRunnerPackage, null) as string;
        if (runnerPath == null)
            throw new InvalidOperationException("Unable to invoke 'GetRunnerPath'.");

        return runnerPath;
    }

    internal override bool IsSupported(RuntimeMoniker runtimeMoniker)
    {
        switch (runtimeMoniker)
        {
            case RuntimeMoniker.HostProcess:
            case RuntimeMoniker.Net461:
            case RuntimeMoniker.Net462:
            case RuntimeMoniker.Net47:
            case RuntimeMoniker.Net471:
            case RuntimeMoniker.Net472:
            case RuntimeMoniker.Net48:
            case RuntimeMoniker.Net481:
            case RuntimeMoniker.Net50:
            case RuntimeMoniker.Net60:

View on GitHub (pinned to b515068b61)

Solutions

Delete the cached prerequisite directory and re-run InitAsync to re-download and extract cleanly.
Verify disk space and write permissions for the cache path.
Check/reconfigure antivirus that may quarantine the JetBrains runner.
Align the SelfApi version with your BDN build.

Defensive patterns

Strategy: fallback

Try / catch

try { /* use dotTrace diagnoser */ }
catch (InvalidOperationException ex) when (ex.Message.Contains("Unable to invoke 'GetRunnerPath'"))
{
    log.Error("dotTrace runner not extracted; check disk/AV/cache and re-run InitAsync.");
}

Prevention

Clear the prerequisite cache so InitAsync re-extracts the runner cleanly.
Ensure disk space and write permissions for the cache path.
Check antivirus quarantine rules for the JetBrains runner exe.

When it happens

Trigger: InitAsync downloaded the prerequisite but the runner executable was not extracted to the expected location, so GetRunnerPath returns null; or the invocation failed internally and SelfApi swallowed it into a null return.

Common situations: Corrupted/interrupted prerequisite download or extraction; antivirus quarantining the runner exe; insufficient disk space/permissions; leftover partial state from a prior failed run.

Related errors

AI-assisted analysis of dotnet/BenchmarkDotNet@b515068b61 (2026-08-13). Data as JSON: /api/errors/0b2b48310ed7b19d. Report an issue: GitHub.