syntax_data: {"ast_node_type":"other","tokens":[{"end":55,"kind":"keyword","start":0,"text":"ui_testing:"}]}
source_snippet:     ui_testing: bool = (false, parse_bool, [UNTRACKED],
context_before:         "emit runtime checks for Undefined Behavior (default: -Cdebug-assertions)"),
context_after:         "emit compiler diagnostics in a form suitable for UI testing (default: no)"),