Run the Perl-based cxxtest instead of the Python (2) version, Py2 is going away
--- residualvm-0.3.1+dfsg.orig/test/module.mk
+++ residualvm-0.3.1+dfsg/test/module.mk
@@ -32,7 +32,7 @@ test/runner: test/runner.cpp $(TEST_LIBS
 	$(QUIET_CXX)$(CXX) $(TEST_CXXFLAGS) $(CPPFLAGS) $(TEST_CFLAGS) -o $@ $+ $(TEST_LDFLAGS)
 test/runner.cpp: $(TESTS)
 	@mkdir -p test
-	$(srcdir)/test/cxxtest/cxxtestgen.py $(TEST_FLAGS) -o $@ $+
+	$(srcdir)/test/cxxtest/cxxtestgen.pl $(TEST_FLAGS) -o $@ $+
 
 clean: clean-test
 clean-test: