Unequal: Don't insist that solve moves must actually solve

A corrupt save file can include an "S" move that doesn't give a valid
solution.  An assertion failure ("execute_move: Assertion `rc > 0'
failed.") at that point is rude, so now we just don't set the
"completed" flag in that case.  We still set the "cheated" flag, to
reward (lack of) effort.

Here's a trivial test case:

SAVEFILE:41:Simon Tatham's Portable Puzzle Collection
GAME    :7:Unequal
CPARAMS :1:3
PARAMS  :1:3
DESC    :17:0,0,0,0,0,0,0,0,0
NSTATES :1:2
STATEPOS:1:2
MOVE    :10:S222222222

1 files changed, 4 insertions, 4 deletions

diff --git a/unequal.c b/unequal.c
index f2328b6..0a2bafd 100644
--- a/unequal.c
+++ b/unequal.c
@@ -1652,7 +1652,7 @@ static char *interpret_move(const game_state *state, game_ui *ui,
 static game_state *execute_move(const game_state *state, const char *move)
 {
     game_state *ret = NULL;
-    int x, y, n, i, rc;
+    int x, y, n, i;
 
     debug(("execute_move: %s", move));
 
@@ -1677,7 +1677,7 @@ static game_state *execute_move(const game_state *state, const char *move)
         const char *p;
 
         ret = dup_game(state);
-        ret->completed = ret->cheated = true;
+        ret->cheated = true;
 
         p = move+1;
         for (i = 0; i < state->order*state->order; i++) {
@@ -1688,8 +1688,8 @@ static game_state *execute_move(const game_state *state, const char *move)
             p++;
         }
         if (*p) goto badmove;
-        rc = check_complete(ret->nums, ret, true);
-	assert(rc > 0);
+        if (!ret->completed && check_complete(ret->nums, ret, true) > 0)
+            ret->completed = true;
         return ret;
     } else if (move[0] == 'M') {
         ret = dup_game(state);