syntax_data: {"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"self.files.borrow().source_files.partition_point(|x|"}]}
source_snippet:         self.files.borrow().source_files.partition_point(|x| x.start_pos <= pos) - 1
context_before:     pub fn lookup_source_file_idx(&self, pos: BytePos) -> usize {
context_after:     }