Test coverage - drink with no valid object

tests/drinkfail.chk

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+
+Welcome to Adventure!!  Would you like instructions?
+
+> n
+
+You are standing at the end of a road before a small brick building.
+Around you is a forest.  A small stream flows out of the building and
+down a gully.
+
+> in
+
+You are inside a building, a well house for a large spring.
+
+There are some keys on the ground here.
+
+There is a shiny brass lamp nearby.
+
+There is food here.
+
+There is a bottle of water here.
+
+> xyzzy
+
+>>Foof!<<
+
+It is now pitch dark.  If you proceed you will likely fall into a pit.
+
+> drink
+
+Drink what?
+
+
+You scored 32 out of a possible 430, using 3 turns.
+
+You are obviously a rank amateur.  Better luck next time.
+
+To achieve the next higher rating, you need 14 more points.

tests/drinkfail.log

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+## Drink unknown
+n
+in
+xyzzy
+drink