Gelatinous cubes eat organic objects inside them

doc/fixes3-7-0.txt

@@ -1486,6 +1486,7 @@ digging in ice was handled inconsistently, particularly if done at the span
 angry god may remove an intrinsic
 blessed scroll of destroy armor asks which armor to destroy
 archeologists' fedora is lucky
+gelatinous cubes eat organic objects inside them
 
 
 Fixes to 3.7.0-x General Problems Exposed Via git Repository

src/monmove.c

@@ -409,6 +409,32 @@ bee_eat_jelly(struct monst *mon, struct obj *obj)
     return -1; /* a queen is already present; ordinary bee hasn't moved yet */
 }
 
+/* gelatinous cube eats something from its inventory */
+static int
+gelcube_digests(struct monst *mtmp)
+{
+    struct obj *otmp = mtmp->minvent;
+
+    if (mtmp->meating || !mtmp->minvent)
+        return -1;
+
+    while (otmp) {
+        if (is_organic(otmp) && !otmp->oartifact
+            && !is_mines_prize(otmp) && !is_soko_prize(otmp))
+            break;
+        otmp = otmp->nobj;
+    }
+
+    if (!otmp)
+        return -1;
+
+    mtmp->meating = eaten_stat(mtmp->meating, otmp);
+    extract_from_minvent(mtmp, otmp, TRUE, TRUE);
+    m_consume_obj(mtmp, otmp);
+    return 0; /* used a move */
+}
+
+
 /* FIXME: gremlins don't flee from monsters wielding Sunsword or wearing
    gold dragon scales/mail, nor from gold dragons, only from the hero */
 #define flees_light(mon) \
@@ -846,6 +872,10 @@ dochug(struct monst *mtmp)
         && (res = bee_eat_jelly(mtmp, otmp)) >= 0)
         return res;
 
+    if (mdat == &mons[PM_GELATINOUS_CUBE]
+        && (res = gelcube_digests(mtmp)) >= 0)
+        return res;
+
     /* A monster that passes the following checks has the opportunity
        to move. Movement itself is handled by the m_move() function. */
     if (!nearby || mtmp->mflee || scared || mtmp->mconf || mtmp->mstun