syntax_data: {"ast_node_type":"other","tokens":[{"end":55,"kind":"keyword","start":0,"text":"self.lookup_char_pos(sp.lo()).file.name.clone()"}]}
source_snippet:         self.lookup_char_pos(sp.lo()).file.name.clone()
context_before:     pub fn span_to_filename(&self, sp: Span) -> FileName {
context_after:     }