{"ast_node_type":"function","tokens":[{"end":98,"kind":"keyword","start":0,"text":"assert_matches(\"$a"}]}
    assert_matches("$a + $b", "fn f() {1 + 2 + 3 + 4}", &["1 + 2", "1 + 2 + 3", "1 + 2 + 3 + 4"]);
fn match_binary_op() {
}