diff --git a/scheduler/filter/expr_test.go b/scheduler/filter/expr_test.go
index 87e960d9a1..b506e4ff44 100644
--- a/scheduler/filter/expr_test.go
+++ b/scheduler/filter/expr_test.go
@@ -19,6 +19,14 @@ func TestParseExprs(t *testing.T) {
 	_, err = parseExprs("constraint", []string{"constraint:no*de==node1"})
 	assert.Error(t, err)
 
+	// Cannot use $ in key
+	_, err = parseExprs("constraint", []string{"constraint:no$de==node1"})
+	assert.Error(t, err)
+
+	// Allow CAPS in key
+	_, err = parseExprs("constraint", []string{"constraint:NoDe==node1"})
+	assert.NoError(t, err)
+
 	// Allow dot in key
 	_, err = parseExprs("constraint", []string{"constraint:no.de==node1"})
 	assert.NoError(t, err)