function mockSimpleGrpcMethod(expectedRequest: {}, response: {} | null, error: FakeError | null) {	
    return (actualRequest: {}, options: {}, callback: Callback) => {	
        assert.deepStrictEqual(actualRequest, expectedRequest);	
        if (error) {	
            callback(error);	
        } else if (response) {	
            callback(null, response);	
        } else {	
            callback(null);	
        }	
    };	
}

function stubSimpleCall<ResponseType>(response?: ResponseType, error?: Error) {
    return error ? sinon.stub().rejects(error) : sinon.stub().resolves([response]);
}

function stubSimpleCallWithCallback<ResponseType>(response?: ResponseType, error?: Error) {
    return error ? sinon.stub().callsArgWith(2, error) : sinon.stub().callsArgWith(2, null, response);
}