diff --git a/tests/ls.cpp b/tests/ls.cpp
index 93ec75b..6d70414 100644
--- a/tests/ls.cpp
+++ b/tests/ls.cpp
@@ -9,6 +9,7 @@
 #include "trompeloeil_doctest.hpp"
 #include "ast_commands.hpp"
 #include "parser.hpp"
+#include "pretty_printers.hpp"
 #include "static_schema.hpp"
 
 TEST_CASE("ls")
diff --git a/tests/pretty_printers.hpp b/tests/pretty_printers.hpp
index fb8aebf..7f59adc 100644
--- a/tests/pretty_printers.hpp
+++ b/tests/pretty_printers.hpp
@@ -110,3 +110,21 @@
     }
     return s;
 }
+
+std::ostream& operator<<(std::ostream& s, const boost::optional<boost::variant<dataPath_, schemaPath_, module_>>& path)
+{
+    if (path) {
+        s << *path;
+    } else {
+        s << "boost::none";
+    }
+
+    return s;
+}
+
+
+std::ostream& operator<<(std::ostream& s, const ls_& ls)
+{
+    s << "\nls_ {\n    " << ls.m_path << "}\n";
+    return s;
+}