Fix issue #51: rug flying is broken

And add a test for the fix.

NEWS

@@ -1,5 +1,8 @@
 = Open Adventure project news =
 
+Repository head::
+  Fixed a bug that manifested after two "fly rug" commands - third one fails.
+
 1.9: 2020-08-27::
   Update the dungeon maker to avoid a deprecation due to security issues
 

actions.c

@@ -845,15 +845,20 @@ static phase_codes_t fly(verb_t verb, obj_t obj)
         rspeak(RUG_NOTHING1);
         return GO_CLEAROBJ;
     }
-    game.oldlc2 = game.oldloc;
-    game.oldloc = game.loc;
 
-    if (game.prop[SAPPH] == STATE_NOTFOUND) {
-        game.newloc = game.place[SAPPH];
+    if (game.loc == LOC_CLIFF) {
+	game.oldlc2 = game.oldloc;
+	game.oldloc = game.loc;
+        game.newloc = LOC_LEDGE;
         rspeak(RUG_GOES);
-    } else {
+    } else if (game.loc == LOC_LEDGE) {
+	game.oldlc2 = game.oldloc;
+	game.oldloc = game.loc;
         game.newloc = LOC_CLIFF;
         rspeak(RUG_RETURNS);
+    } else {
+	/* should never happen */
+	rspeak(NOTHING_HAPPENS);
     }
     return GO_TERMINATE;
 }

tests/flyback.log

@@ -0,0 +1,343 @@
+## Test fix for issue #51: rug flying is broken
+n
+seed 1838473132
+in
+take lamp
+xyzzy
+on
+take rod
+e
+take cage
+w
+w
+w
+drop rod
+take bird
+take rod
+w
+free bird
+wave rod
+take necklace
+drop rod
+take bird
+take rod
+d
+d
+free bird
+drop rod
+drop cage
+take cage
+take bird
+w
+take coins
+e
+s
+take jewelry
+n
+up
+s
+take gold
+n
+d
+n
+n
+plugh
+extinguish lamp
+drop coins
+drop jewelry
+drop necklace
+drop gold
+plugh
+on
+s
+take silver
+s
+sw
+take axe
+w
+kill dragon
+yes
+drink blood
+take rug
+e
+e
+up
+d
+n
+n
+off
+plugh
+inven
+drop rug
+drop silver
+out
+s
+w
+n
+take appendage
+free bird
+drop cage
+listen
+s
+s
+n
+in
+take water
+plugh
+on
+plover
+ne
+take pyramid
+s
+plover
+s
+s
+take rod
+up
+w
+wave rod
+drop rod
+west
+take diamonds
+w
+w
+w
+s
+sw
+se
+s
+kill machine
+s
+s
+kill ogre
+n
+take ruby
+s
+w
+n
+n
+n
+nw
+d
+e
+e
+e
+e
+e
+throw axe
+take axe
+n
+n
+n
+off
+plugh
+drop ruby
+drop diamonds
+drop pyramid
+plugh
+on
+s
+s
+u
+n
+n
+d
+bedquilt
+throw axe
+take axe
+slab
+s
+d
+water plant
+u
+w
+u
+reservoir
+H'CFL
+n
+n
+nw
+u
+u
+u
+u
+ne
+take ebony
+sw
+d
+d
+d
+d
+d
+take water
+s
+s
+s
+s
+d
+s
+d
+water plant
+u
+drop appendage
+e
+d
+get oil
+
+u
+w
+d
+climb
+w
+n
+oil door
+drop bottle
+n
+take trident
+w
+d
+se
+n
+w
+drop trident
+drop ebony
+drop axe
+drop lantern
+e
+take emerald
+w
+take lamp
+take axe
+take ebony
+take trident
+nw
+s
+take vase
+se
+throw axe
+take axe
+e
+take pillow
+w
+drop axe
+ne
+e
+n
+open clam
+s
+u
+e
+u
+n
+off
+plugh
+drop pillow
+drop vase
+drop trident
+drop emerald
+drop ebony
+take keys
+take food
+plugh
+on
+s
+d
+w
+d
+n
+d
+d
+take pearl
+u
+u
+s
+w
+w
+w
+w
+d
+climb
+w
+get eggs
+n
+take bottle
+n
+w
+d
+sw
+u
+toss eggs
+ne
+ne
+barren
+in
+feed bear
+unlock chain
+take chain
+take bear
+fork
+ne
+e
+take spices
+fork
+w
+w
+sw
+free bear
+sw
+sw
+d
+se
+se
+w
+d
+get oil
+up
+e
+take axe
+w
+w
+d
+climb
+w
+fee
+fie
+foe
+foo
+take eggs
+s
+d
+u
+w
+u
+s
+e
+e
+n
+drop keys
+n
+off
+plugh
+drop eggs
+drop pearl
+drop spices
+drop chain
+take rug
+take ruby
+take emerald
+out
+w
+n
+n
+n
+inven
+fill urn
+light urn
+rub urn
+take amber
+drop rug
+drop emerald
+fly rug
+fly rug
+fly rug
+