syntax_data: {"ast_node_type":"other","tokens":[{"end":39,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // Remap filename before lookup
context_before:     pub fn get_source_file(&self, filename: &FileName) -> Option<Arc<SourceFile>> {
context_after:         let filename = self.path_mapping().map_filename_prefix(filename).0;