probing vs underwater items

When probing is zapped downward while hero is at a water or lava spot
and hero isn't beneath the surface, show any objects 'hidden' by the
water or lava at that spot.

doc/fixes3-7-0.txt

@@ -1,4 +1,4 @@
-$NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.1247 $ $NHDT-Date: 1695932713 2023/09/28 20:25:13 $
+$NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.1268 $ $NHDT-Date: 1698090922 2023/10/23 19:55:22 $
 
 General Fixes and Modified Features
 -----------------------------------
@@ -1239,6 +1239,8 @@ paranoid_confirm:pray can be changed to require yes/no response instead of y/n
 	by also setting paranoid_confirm:Confirm
 wand of probing reveals map locations and traps in the ray path; also reveals
 	secret doors and secret corridors if the ray hits such
+wand of probing zapped downward while hero is over water shows items under that
+wand of probing reveals tin and egg contents
 applying a wielded, lit potion of oil to unlight it while other unlit
 	potion(s) of oil were quivered would trigger panic
 	"addinv: null obj after quiver merge otyp=N" where N is POT_OIL
@@ -1250,7 +1252,6 @@ the throne room on the Samurai quest home level lacked a throne but gave
 coughing due to stinking cloud wakes up nearby monsters
 stop occupation when timed levitation or choking issues a message
 use #monster to make dragon steed breathe
-wand of probing reveals tin and egg contents
 steam vortices and fog clouds leave steam clouds behind
 fog clouds maintain any clouds they are in, even poisonous ones
 bone devils summon skeletons

src/invent.c

@@ -1,4 +1,4 @@
-/* NetHack 3.7	invent.c	$NHDT-Date: 1698017900 2023/10/22 23:38:20 $  $NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.455 $ */
+/* NetHack 3.7	invent.c	$NHDT-Date: 1698090922 2023/10/23 19:55:22 $  $NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.456 $ */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /*-Copyright (c) Derek S. Ray, 2015. */
 /* NetHack may be freely redistributed.  See license for details. */
@@ -5527,8 +5527,8 @@ only_here(struct obj *obj)
 }
 
 /*
- * Display a list of buried items in inventory style.  Return a non-zero
+ * Display a list of buried or underwater items in inventory style.
- * value if there were items at that spot.
+ * Return a non-zero value if there were items at that spot.
  *
  * Currently, this is only used with a wand of probing zapped downwards.
  */
@@ -5536,10 +5536,42 @@ int
 display_binventory(coordxy x, coordxy y, boolean as_if_seen)
 {
     struct obj *obj;
+    char qbuf[QBUFSZ];
+    const char *underwhat = "here";
     menu_item *selected = 0;
-    int n;
+    int n, n2 = 0;
 
-    /* count # of objects here */
+    /* if hero is levitating or flying over water or lava, list any items
+       below (the map won't be showing them); if hero is underwater, player
+       should use the normal look_here command instead of probing (caller
+       has already used bhitpile() which will have set dknown on all items) */
+    if (is_pool_or_lava(x, y) && !Underwater
+        && (obj = gl.level.objects[x][y]) != 0) {
+        const char *real_liquid = is_pool(x, y) ? "water" : "lava",
+                   *seen_liquid = hliquid(real_liquid);
+
+        if (!obj->nexthere) {
+            boolean more_than_1 = is_plural(obj);
+
+            There("%s %s under the %s here.", more_than_1 ? "are" : "is",
+                  doname(obj), seen_liquid);
+            n2 = 1;
+            /* "pair of boots" is singular but "beneath it" sounds strange */
+            if (pair_of(obj))
+                more_than_1 = TRUE;
+            underwhat = more_than_1 ? "under them" : "beneath it";
+        } else {
+            Sprintf(qbuf, "Things that are under the %s here:", seen_liquid);
+            if (query_objlist(qbuf, &gl.level.objects[x][y], BY_NEXTHERE,
+                              &selected, PICK_NONE, allow_all) > 0)
+                free((genericptr_t) selected), selected = 0;
+            for (n2 = 0; obj; obj = obj->nexthere)
+                ++n2;
+            underwhat = "beneath them";
+        }
+    }
+
+    /* count # of buried objects here */
     for (n = 0, obj = gl.level.buriedobjlist; obj; obj = obj->nobj)
         if (obj->ox == x && obj->oy == y) {
             if (as_if_seen)
@@ -5550,13 +5582,14 @@ display_binventory(coordxy x, coordxy y, boolean as_if_seen)
     if (n) {
         go.only.x = x;
         go.only.y = y;
-        if (query_objlist("Things that are buried here:",
+        /* "buried here", but vary if we've already shown underwater items */
-                          &gl.level.buriedobjlist, INVORDER_SORT,
+        Sprintf(qbuf, "Things that are buried %s:", underwhat);
+        if (query_objlist(qbuf, &gl.level.buriedobjlist, INVORDER_SORT,
                           &selected, PICK_NONE, only_here) > 0)
             free((genericptr_t) selected);
         go.only.x = go.only.y = 0;
     }
-    return n;
+    return n + n2;
 }
 
 void