\documentclass{testsuite} \usepackage{fontspec} \begin{document} \ExplSyntaxOn LM~is \fontspec_if_fontspec_font:TF {\ERROR}{~not~a~fontspec~font.\par} \setmainfont{TeX~ Gyre~ Pagella} TeX Gyre Pagella \fontspec_if_fontspec_font:TF {~is~a~fontspec~font}{\ERROR} \fontspec_if_opentype:TF {,~is~OpenType}{\ERROR} \fontspec_if_feature:nTF {smcp}{,~has~small~caps}{\ERROR} \fontspec_if_current_script:nTF {latn}{,~is~using~Latin~script}{\ERROR} \fontspec_if_script:nTF {cyrl}{,~also~has~Cyrillic}{\ERROR} \fontspec_if_current_language:nTF {DFLT}{,~is~using~`default'~language}{\ERROR} \fontspec_if_language:nnTF {latn}{ROM}{,~also~has~Romanian}{\ERROR} \end{document}