diff --git a/test/lib/library.exp b/test/lib/library.exp
index 968d7809..e5ce9716 100644
--- a/test/lib/library.exp
+++ b/test/lib/library.exp
@@ -591,6 +591,7 @@ proc _save_env {{file ""}} {
 # Source bash_completion package
 proc source_bash_completion {} {
     assert_bash_exec {BASH_COMPLETION_DIR=$(cd $TESTDIR/..; pwd)/contrib}
+    assert_bash_exec {BASH_COMPLETION_COMPAT_DIR=$BASH_COMPLETION_DIR}
     assert_bash_exec {BASH_COMPLETION=$(cd $TESTDIR/..; pwd)/bash_completion}
     assert_bash_exec {source $BASH_COMPLETION}
 }; # source_bash_completion()