fix github issue #109 - healing spells

Fixes #109

Spells of healing and extra healing cast at monsters were handling
monster blindness differently from other forms of healing.  (Potions
also work differently when drunk by monsters but I haven't changed
that since it seems to be intentional.)

Hero:
   potion of healing cures blindness if blessed; spell of healing
      cast at skilled or better now behaves likewise;
   potion of extra healing cures blindness if not cursed; spell of
      extra healing is inherently not cursed and already behaved
      likewise;
   potion of full healing always cures blindness even if cursed.

Monsters quaffing potions:
   plain healing cures blindness if not cursed;
   extra healing and full healing always cure blindess.

Hero casting healing spell at monster:
   plain healing behaves like the hero plain healing case:  cures
      blindness as if blessed when cast at skilled or expert level;
      this is a change in hehavior--it used to cure timed blindness
      even if unskilled and not cure 'permanent' blindness at all;
   extra healing cast by hero is inherently not cursed so always
      cures blindness.

doc/fixes36.2

@@ -44,6 +44,8 @@ wishing for small mimic corpse or large mimic corpse failed with 'nothing
 	yielded normal size one (size prefix was being stripped off for globs)
 wishing for "glob of grey ooze" failed even though grey ooze is recognized
 	as a variant spelling for gray ooze
+spells of healing and extra healing cast at monsters handled monster blindness
+	inconsistently compared to other healing
 
 
 Fixes to Post-3.6.1 Problems that Were Exposed Via git Repository

src/spell.c

@@ -886,7 +886,7 @@ int spell;
 boolean atme;
 {
     int energy, damage, chance, n, intell;
-    int skill, role_skill, res = 0;
+    int otyp, skill, role_skill, res = 0;
     boolean confused = (Confusion != 0);
     boolean physical_damage = FALSE;
     struct obj *pseudo;
@@ -1029,10 +1029,11 @@ boolean atme;
      * Find the skill the hero has in a spell type category.
      * See spell_skilltype for categories.
      */
-    skill = spell_skilltype(pseudo->otyp);
+    otyp = pseudo->otyp;
+    skill = spell_skilltype(otyp);
     role_skill = P_SKILL(skill);
 
-    switch (pseudo->otyp) {
+    switch (otyp) {
     /*
      * At first spells act as expected.  As the hero increases in skill
      * with the appropriate spell type, some spells increase in their
@@ -1056,9 +1057,9 @@ boolean atme;
                         }
                     } else {
                         explode(u.dx, u.dy,
-                                pseudo->otyp - SPE_MAGIC_MISSILE + 10,
+                                otyp - SPE_MAGIC_MISSILE + 10,
                                 spell_damage_bonus(u.ulevel / 2 + 1), 0,
-                                (pseudo->otyp == SPE_CONE_OF_COLD)
+                                (otyp == SPE_CONE_OF_COLD)
                                    ? EXPL_FROSTY
                                    : EXPL_FIERY);
                     }
@@ -1073,12 +1074,13 @@ boolean atme;
                 }
             }
             break;
-        } /* else fall through... */
+        } /* else */
+        /*FALLTHRU*/
 
     /* these spells are all duplicates of wand effects */
     case SPE_FORCE_BOLT:
         physical_damage = TRUE;
-    /* fall through */
+    /*FALLTHRU*/
     case SPE_SLEEP:
     case SPE_MAGIC_MISSILE:
     case SPE_KNOCK:
@@ -1096,7 +1098,13 @@ boolean atme;
     case SPE_EXTRA_HEALING:
     case SPE_DRAIN_LIFE:
     case SPE_STONE_TO_FLESH:
-        if (!(objects[pseudo->otyp].oc_dir == NODIR)) {
+        if (objects[otyp].oc_dir != NODIR) {
+            if (otyp == SPE_HEALING || otyp == SPE_EXTRA_HEALING) {
+                /* healing and extra healing are actually potion effects,
+                   but they've been extended to take a direction like wands */
+                if (role_skill >= P_SKILLED)
+                    pseudo->blessed = 1;
+            }
             if (atme) {
                 u.dx = u.dy = u.dz = 0;
             } else if (!getdir((char *) 0)) {
@@ -1136,7 +1144,7 @@ boolean atme;
         /* high skill yields effect equivalent to blessed scroll */
         if (role_skill >= P_SKILLED)
             pseudo->blessed = 1;
-    /* fall through */
+    /*FALLTHRU*/
     case SPE_CHARM_MONSTER:
     case SPE_MAGIC_MAPPING:
     case SPE_CREATE_MONSTER:
@@ -1152,7 +1160,7 @@ boolean atme;
         /* high skill yields effect equivalent to blessed potion */
         if (role_skill >= P_SKILLED)
             pseudo->blessed = 1;
-    /* fall through */
+    /*FALLTHRU*/
     case SPE_INVISIBILITY:
         (void) peffects(pseudo);
         break;

src/zap.c

@@ -138,7 +138,7 @@ struct obj *otmp;
     boolean wake = TRUE; /* Most 'zaps' should wake monster */
     boolean reveal_invis = FALSE, learn_it = FALSE;
     boolean dbldam = Role_if(PM_KNIGHT) && u.uhave.questart;
-    boolean helpful_gesture = FALSE;
+    boolean skilled_spell, helpful_gesture = FALSE;
     int dmg, otyp = otmp->otyp;
     const char *zap_type_text = "spell";
     struct obj *obj;
@@ -149,10 +149,12 @@ struct obj *otmp;
         reveal_invis = FALSE;
 
     notonhead = (mtmp->mx != bhitpos.x || mtmp->my != bhitpos.y);
+    skilled_spell = (otmp && otmp->oclass == SPBOOK_CLASS && otmp->blessed);
+
     switch (otyp) {
     case WAN_STRIKING:
         zap_type_text = "wand";
-    /* fall through */
+    /*FALLTHRU*/
     case SPE_FORCE_BOLT:
         reveal_invis = TRUE;
         if (disguised_mimic)
@@ -343,10 +345,12 @@ struct obj *otmp;
             mtmp->mhp += d(6, otyp == SPE_EXTRA_HEALING ? 8 : 4);
             if (mtmp->mhp > mtmp->mhpmax)
                 mtmp->mhp = mtmp->mhpmax;
-            if (mtmp->mblinded) {
+            /* plain healing must be blessed to cure blindness; extra
-                mtmp->mblinded = 0;
+               healing only needs to not be cursed, so spell always cures
-                mtmp->mcansee = 1;
+               [potions quaffed by monsters behave slightly differently;
-            }
+               we use the rules for the hero here...] */
+            if (skilled_spell || otyp == SPE_EXTRA_HEALING)
+                mcureblindness(mtmp, canseemon(mtmp));
             if (canseemon(mtmp)) {
                 if (disguised_mimic) {
                     if (is_obj_mappear(mtmp,STRANGE_OBJECT)) {
@@ -2407,7 +2411,7 @@ boolean ordinary;
     case SPE_EXTRA_HEALING:
         learn_it = TRUE; /* (no effect for spells...) */
         healup(d(6, obj->otyp == SPE_EXTRA_HEALING ? 8 : 4), 0, FALSE,
-               (obj->otyp == SPE_EXTRA_HEALING));
+               (obj->blessed || obj->otyp == SPE_EXTRA_HEALING));
         You_feel("%sbetter.", obj->otyp == SPE_EXTRA_HEALING ? "much " : "");
         break;
     case WAN_LIGHT: /* (broken wand) */