Description

Calling an overloaded .NET method from Python with an empty **kwargs mapping (e.g. obj.Method(arg, **{}), common when forwarding *args/**kwargs from a wrapper or decorator) crashed with an unhandled System.IndexOutOfRangeException in MethodBinder.CheckMethodArgumentsMatch. The exception escapes through tp_call as a CLR exception, so it cannot be caught from Python and tears down the host process (crashes LEAN during Initialize()).

Closes #132

Also bumps the package version to 2.0.60 (package <Version>, AssemblyVersion/AssemblyFileVersion and the perf-test baseline reference, following the same pattern as #131).

Root cause

Since 10e721b (#83), the parameter names array is only populated when there are named arguments (hasNamedArgs ? methodInformation.ParameterNames : Array.Empty<string>()), but the kwargs code paths in CheckMethodArgumentsMatch and Bind only checked the kwargs dictionary for null. A non-null but empty kwargs dict therefore routed binding through the kwargs path while paramNames was empty, indexing out of range for any overload with more CLR parameters than positional Python arguments. Bisect-confirmed: 10e721b~1 binds fine, 10e721b crashes.

Fix

Treat an empty kwargs dict as no keyword arguments: MethodBinder.Bind only builds kwArgDict when PyDict_Size(kw) > 0, so **{} follows the exact same code path as a plain positional call. This matches pure Python semantics, where f(x, **{}) is equivalent to f(x), and restores the invariant that a non-null kwArgDict implies populated parameter names.

Testing

• New TestMethodBinder.BindsOverloadedMethodCalledWithEmptyOrUnpackedKwargs covering empty **{} against overloads of different arity, empty **{} mixed with a named argument, non-empty dict unpacking, overloads with default parameter values, and the *args/**kwargs forwarding idiom from the issue. Without the fix, these crash the test host.
• Full embedding test suite passes (927 passed, 0 failed).
• Full CI suite replicated locally in the quantconnect/lean:foundation container (Python 3.11.14): embedding tests 928/928, pytest suite 454 passed, python_tests_runner 2/2.
• Verified in LEAN: the issue's get_parameter wrapper algorithm crashes on the current binaries and completes successfully with the fixed Python.Runtime.dll.