From: Pasi Kallinen <paxed@alt.org>
Date: Fri, 18 Mar 2022 16:33:32 +0000 (+0200)
Subject: Fix dmonsfree pending when hero was hit with drain-life artifact
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=81ef433def1807a317ac92787bbc9d0d876c106c;p=nethack

Fix dmonsfree pending when hero was hit with drain-life artifact

When a monster hit hero with an artifact with drain-life attack
(Stormbringer or The Staff of Aesculapius), and hero lost a level
and hero had more max hp in the lower xp level, the math made the
attacker lose hp. This could put the monster hp in the negative,
causing "dmonsfree: 1 removed doesn't match 0 pending"
---

diff --git a/src/artifact.c b/src/artifact.c
index 18d981b21..7e3ca12a2 100644
--- a/src/artifact.c
+++ b/src/artifact.c
@@ -1589,7 +1589,7 @@ artifact_hit(struct monst *magr, struct monst *mdef, struct obj *otmp,
             }
             losexp("life drainage");
             if (magr && magr->mhp < magr->mhpmax) {
-                magr->mhp += (oldhpmax - u.uhpmax + 1) / 2;
+                magr->mhp += (abs(oldhpmax - u.uhpmax) + 1) / 2;
                 if (magr->mhp > magr->mhpmax)
                     magr->mhp = magr->mhpmax;
             }