Potions of hallucination can give enlightenment

This is also from SliceHack, but with the odds of enlightenment toned
down a bit, to 4/9 for a blessed potion and 1/6 for an uncursed potion
(SliceHack had it at 50% blessed, 20% cursed, and strangely, 0%
uncursed). It gives a much-needed use to one of the potions that's
commonly blanked or discarded.

doc/fixes37.0

@@ -108,6 +108,7 @@ make non-tame (baby) purple worms eat corpses off the ground
 make baby purple worms attack shriekers
 make hero polymorphed into baby purple worm warned against shriekers
 confused scroll of light summons tame cancelled lights
+potions of hallucination can give enlightenment
 
 
 Fixes to 3.7.0-x Problems that Were Exposed Via git Repository

src/potion.c

@@ -632,11 +632,22 @@ register struct obj *otmp;
         }
         break;
     case POT_HALLUCINATION:
-        if (Hallucination || Halluc_resistance)
+        if (Halluc_resistance) {
             g.potion_nothing++;
+            break;
+        } else if (Hallucination) {
+            g.potion_nothing++;
+        }
         (void) make_hallucinated(itimeout_incr(HHallucination,
                                           rn1(200, 600 - 300 * bcsign(otmp))),
                                  TRUE, 0L);
+        if ((otmp->blessed && !rn2(3)) || (!otmp->cursed && !rn2(6))) {
+            You("perceive yourself...");
+            display_nhwindow(WIN_MESSAGE, FALSE);
+            enlightenment(MAGICENLIGHTENMENT, ENL_GAMEINPROGRESS);
+            Your("awareness re-normalizes.");
+            exercise(A_WIS, TRUE);
+        }
         break;
     case POT_WATER:
         if (!otmp->blessed && !otmp->cursed) {