-# Set up GIT_DIR and GIT_OBJECT_DIRECTORY
-# and return true if everything looks ok
-#
-: ${GIT_DIR=.git}
-: ${GIT_OBJECT_DIRECTORY="$GIT_DIR/objects"}
+# This is included in commands that either have to be run from the toplevel
+# of the repository, or with GIT_DIR environment variable properly.
+# If the GIT_DIR does not look like the right correct git-repository,
+# it dies.