syntax_data: {"ast_node_type":"other","tokens":[{"end":48,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:         if !self.source_map.files().is_empty() {
context_before:     fn file_for_position(&self, pos: BytePos) -> Option<(Arc<SourceFile>, usize)> {
context_after:             let file_idx = self.source_map.lookup_source_file_idx(pos);