fix #H4083 - globs preID'd as "uncursed"

I think there was also a report about this during beta testing.
Killing an ooze, slime, or pudding left a glob of same which had its
bknown flag pre-set so was immediately shown as "uncursed" even to
non-priests.  Use another way to maximize glob mergability:  allow
globs to merge even when one has bknown set and the other doesn't.

doc/fixes36.1

@@ -104,6 +104,10 @@ covetous monsters may choose to teleport to downstairs or ladders
 doppelganger posing as Rider would never change shape
 since doppelganger posing as Rider could never revert to innate form,
 	protection from shape changers turned it into genuine Rider
+don't create globs of ooze/slime/pudding with bknown flag set so pre-known to
+	be "uncursed"
+do allow globs with same curse/bless state to merge even when that state is
+	known for one and unknown for the other; result will have bknown clear
 
 
 Platform- and/or Interface-Specific Fixes

src/invent.c

@@ -2880,24 +2880,46 @@ mergable(otmp, obj)
 register struct obj *otmp, *obj;
 {
     int objnamelth = 0, otmpnamelth = 0;
+
     if (obj == otmp)
         return FALSE; /* already the same object */
     if (obj->otyp != otmp->otyp)
+        return FALSE; /* different types */
+    if (obj->nomerge) /* explicitly marked to prevent merge */
         return FALSE;
+
     /* coins of the same kind will always merge */
     if (obj->oclass == COIN_CLASS)
         return TRUE;
+
     if (obj->unpaid != otmp->unpaid || obj->spe != otmp->spe
         || obj->dknown != otmp->dknown
-        || (obj->bknown != otmp->bknown && !Role_if(PM_PRIEST))
         || obj->cursed != otmp->cursed || obj->blessed != otmp->blessed
         || obj->no_charge != otmp->no_charge || obj->obroken != otmp->obroken
         || obj->otrapped != otmp->otrapped || obj->lamplit != otmp->lamplit
-        || obj->greased != otmp->greased || obj->oeroded != otmp->oeroded
-        || obj->oeroded2 != otmp->oeroded2 || obj->bypass != otmp->bypass)
+        || obj->bypass != otmp->bypass)
         return FALSE;
 
-    if (obj->nomerge) /* explicitly marked to prevent merge */
+    if (obj->oclass == FOOD_CLASS
+        && (obj->oeaten != otmp->oeaten || obj->orotten != otmp->orotten))
+        return FALSE;
+
+    if (obj->globby) {
+        /* globs won't merge if they have different bless/curse
+           state, but will merge non-bknown with bknown */
+        if (obj->bknown != otmp->bknown)
+            obj->bknown = otmp->bknown = 0;
+        if (obj->rknown != otmp->rknown)
+            obj->rknown = otmp->rknown = 0;
+        if (obj->greased != otmp->greased)
+            obj->greased = otmp->greased = 0;
+        /* checks beyond this point aren't applicable to globs */
+        return TRUE;
+    }
+
+    if ((obj->bknown != otmp->bknown && !Role_if(PM_PRIEST))
+        || obj->oeroded != otmp->oeroded || obj->oeroded2 != otmp->oeroded2
+        || obj->greased != otmp->greased)
         return FALSE;
 
     if ((obj->oclass == WEAPON_CLASS || obj->oclass == ARMOR_CLASS)
@@ -2905,10 +2927,6 @@ register struct obj *otmp, *obj;
             || obj->rknown != otmp->rknown))
         return FALSE;
 
-    if (obj->oclass == FOOD_CLASS
-        && (obj->oeaten != otmp->oeaten || obj->orotten != otmp->orotten))
-        return FALSE;
-
     if (obj->otyp == CORPSE || obj->otyp == EGG || obj->otyp == TIN) {
         if (obj->corpsenm != otmp->corpsenm)
             return FALSE;
@@ -3413,6 +3431,7 @@ doorganize() /* inventory organizer by Del Lamb */
                    names, strip off the name of the one being moved */
                 if (olth && !obj->oartifact && !mergable(otmp, obj)) {
                     char *holdname = ONAME(obj);
+
                     ONAME(obj) = (char *) 0;
                     /* restore name iff merging is still not possible */
                     if (!mergable(otmp, obj)) {

src/mkobj.c

@@ -819,11 +819,9 @@ boolean artif;
             }
             if (Is_pudding(otmp)) {
                 otmp->globby = 1;
-                otmp->known = otmp->bknown = otmp->rknown = otmp->dknown = 1;
-                otmp->corpsenm =
-                    PM_GRAY_OOZE + (otmp->otyp - GLOB_OF_GRAY_OOZE);
-                /* this ensures that they don't fail merging because of
-                 * BUC status or other irrelevancies */
+                otmp->known = otmp->dknown = 1;
+                otmp->corpsenm = PM_GRAY_OOZE
+                                 + (otmp->otyp - GLOB_OF_GRAY_OOZE);
             } else {
                 if (otmp->otyp != CORPSE && otmp->otyp != MEAT_RING
                     && otmp->otyp != KELP_FROND && !rn2(6)) {