contract

Is an agreement made between friends considered to be unenforceable or is presumed by the court to be unenforceable

Also if person x agrees to sell a piece of land to person y for free, and then this agreement is made in writing, is it enforceable even though there is one way consideration from person x but no consideration from person y. If it is enforceable then what is the rationale ( ratio decendi) for it being enforceable.