{"ast_node_type":"variable","tokens":[{"end":49,"kind":"keyword","start":0,"text":"let"}]}
    let offset = range_or_offset.expect_offset();
    let (file_id, range_or_offset) = change_fixture.file_position.expect("expected a marker ($0)");
    let position = FilePosition { file_id: file_id.file_id(&database), offset };