Is there a way to test a request's configuration?

Deno.test("authenticate() uses the expected request", async () => {

    // arrange
    const mockFetch = new MockFetch();
    mockFetch
        .intercept('https://authentication.xxx.com/connect/token', { method: "POST" })
        .response(JSON.stringify({
            access_token: crypto.randomUUID(),
            expires_in: 604800
        }), { status: 200 });

    const client_id = crypto.randomUUID();
    const client_secret = crypto.randomUUID();

    const body = {
        grant_type: 'password',
        client_id: client_id,
        client_secret: client_secret,
    }
    const formBody = Object.keys(body)
        .map(key => encodeURIComponent(key) + '=' + encodeURIComponent(body[key])).join('&');

    const client = new Client(client_id,client_secret);
    
    // act  
    await client.authenticate();

    // assert
    assertEquals(mockFetch.request.url, 'https://authentication.xxx.com/connect/token');
    assertEquals(mockFetch.request.method, 'POST');
    assertEquals(mockFetch.request.headers('Content-Type'), 'application/x-www-form-urlencoded');
    assertEquals(mockFetch.request.body, formBody);

});