I mostly agree with Rusty.
This usage of the present indicative with "tú" in this kind of context, is often used as an imperative.
- Aquí te quedas mientras compro tu helado.
Quédate aquí mientras...
You stay here while I buy your ice-cream.
- ¡Ah, no, de aquí no te vas hasta que me respondas lo que te pregunté!
No te vayas hasta que...
Oh no, you aren't leaving until you answer the question I asked you!
- ¿Cómo que ya no nos vamos a casar? ¡Ahora me explicas por qué!
Explícame por qué...
What do you mean we're not getting married? You have to explain why right now!
- ¡Te comes toda la sopa y sin llorar!
Cómete toda la sopa!
I said you must eat all your soup and don't cry!