Near the end of macroparse.compiler.compile_string(...) is a call to ebnf.sugarless_form() which may return None if no production rules are defined (and thus there's no start symbol) but the caller assumes a ContextFreeGrammar comes back and tries to make a table of it.
An automatic test for this would consist of compiling a simple scanner-only document (in-line) and asserting the result has a scanner table. Probably there should be no parse table, but scanner-only applications do exist and they should be supported in this manner. Accordingly, the test might continue on to apply the generated scanner-table in a "typical application" scenario, scan a few tokens, assert they are as expected, and then pass.
Near the end of
macroparse.compiler.compile_string(...)is a call toebnf.sugarless_form()which may returnNoneif no production rules are defined (and thus there's no start symbol) but the caller assumes aContextFreeGrammarcomes back and tries to make a table of it.An automatic test for this would consist of compiling a simple scanner-only document (in-line) and asserting the result has a scanner table. Probably there should be no parse table, but scanner-only applications do exist and they should be supported in this manner. Accordingly, the test might continue on to apply the generated scanner-table in a "typical application" scenario, scan a few tokens, assert they are as expected, and then pass.