R772.2 - potions of acid in pools

- mixing potions of acid and water result in an explosion, so water_damage
should cause a potion of acid to explode as well

doc/fixes34.1

@@ -70,6 +70,7 @@ ATR_BOLD on spell menu header
 travel command should restrict its shortest paths to areas of the map the
 	hero knows about or might reasonably guess
 non-altar prayer should limit god action, not maximize it
+potions of acid explode, not dilute, so make water_damage behave this way
 
 
 Platform- and/or Interface-Specific Fixes

src/trap.c

@@ -2418,9 +2418,12 @@ water_damage(obj, force, here)
 register struct obj *obj;
 register boolean force, here;
 {
+	struct obj *otmp;
+
 	/* Scrolls, spellbooks, potions, weapons and
 	   pieces of armor may get affected by the water */
-	for (; obj; obj = (here ? obj->nexthere : obj->nobj)) {
+	for (; obj; obj = otmp) {
+		otmp = here ? obj->nexthere : obj->nobj;
 
 		(void) snuff_lit(obj);
 
@@ -2452,7 +2455,12 @@ register boolean force, here;
 				pline("Steam rises from %s.", the(xname(obj)));
 			else obj->otyp = SPE_BLANK_PAPER;
 		} else if (obj->oclass == POTION_CLASS) {
-			if (obj->odiluted) {
+			if (obj->otyp == POT_ACID) {
+				/* damage player/monster? */
+				pline("A potion explodes!");
+				delobj(obj);
+				continue;
+			} else if (obj->odiluted) {
 				obj->otyp = POT_WATER;
 				obj->blessed = obj->cursed = 0;
 				obj->odiluted = 0;