PluralKit/crates/command_parser/tests/parser.rs

use command_parser::{Tree, command::Command, parameter::*, parse_command, tokens};

/// this checks if we properly keep track of filtered tokens (eg. branches we failed on)
/// when we backtrack. a previous parser bug would cause infinite loops since it did not
/// (the parser would "flip-flop" between branches) this is here for reference.
#[test]
fn test_infinite_loop_repro() {
    let p1 = Optional(("param1", ParameterKind::OpaqueString));
    let p2 = Optional(("param2", ParameterKind::OpaqueString));

    let cmd1 = Command::new(tokens!("s", p1, "A"), "cmd1");
    let cmd2 = Command::new(tokens!("s", p2, "B"), "cmd2");

    let mut tree = Tree::default();
    tree.register_command(cmd1);
    tree.register_command(cmd2);

    let input = "s foo C";
    // this should fail and not loop
    let result = parse_command(tree, "pk;".to_string(), input.to_string());
    assert!(result.is_err());
}

/// check if we have params from other branches when we trying to match them and they succeeded
/// but then we backtracked, making them invalid. this should no longer happen since we just
/// extract params from matched tokens when we match the command, but keeping here just for reference.
#[test]
fn test_dirty_params() {
    let p1 = Optional(("param1", ParameterKind::OpaqueString));
    let p2 = Optional(("param2", ParameterKind::OpaqueString));

    let cmd1 = Command::new(tokens!("s", p1, "A"), "cmd1");
    let cmd2 = Command::new(tokens!("s", p2, "B"), "cmd2");

    let mut tree = Tree::default();
    tree.register_command(cmd1);
    tree.register_command(cmd2);

    let input = "s foo B";
    let result = parse_command(tree, "pk;".to_string(), input.to_string()).unwrap();

    println!("params: {:?}", result.parameters);
    assert!(
        !result.parameters.contains_key("param1"),
        "params should not contain 'param1' from failed branch"
    );
    assert!(
        result.parameters.contains_key("param2"),
        "params should contain 'param2'"
    );
}