/usr/share/openscad/regression/echotest/ is in openscad-testing-data 2013.01+dfsg-2.2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/openscad/regression/echotest/builtin-tests-expected.txt
/usr/share/openscad/regression/echotest/dim-all-expected.txt
/usr/share/openscad/regression/echotest/echo-expected.txt
/usr/share/openscad/regression/echotest/echo-tests-expected.txt
/usr/share/openscad/regression/echotest/escape-test-expected.txt
/usr/share/openscad/regression/echotest/inf-tests-expected.txt
/usr/share/openscad/regression/echotest/len-tests-expected.txt
/usr/share/openscad/regression/echotest/parser-tests-expected.txt
/usr/share/openscad/regression/echotest/recursion-tests-expected.txt
/usr/share/openscad/regression/echotest/search-tests-expected.txt
/usr/share/openscad/regression/echotest/string-indexing-expected.txt
/usr/share/openscad/regression/echotest/string-test-expected.txt
/usr/share/openscad/regression/echotest/vector-values-expected.txt