lalrpop 0.23.0

convenient LR(1) parser generator
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55

use super::inline_order;
use crate::grammar::repr::NonterminalString;
use crate::normalize::lower_helper;
use crate::parser;
use crate::session::Session;
use string_cache::DefaultAtom as Atom;

#[test]
fn test_inline_self_cycle() {
    let grammar = parser::parse_grammar(
        r#"
    grammar;
    extern { }
    #[inline] A: () = A;
"#,
    )
    .unwrap();
    let grammar = lower_helper(&Session::test(), grammar, true).unwrap();
    assert!(inline_order(&grammar).is_err());
}

#[test]
fn test_inline_cycle_3() {
    let grammar = parser::parse_grammar(
        r#"
    grammar;
    extern { }
    #[inline] A: () = B;
    #[inline] B: () = C;
    #[inline] C: () = A;
"#,
    )
    .unwrap();
    let grammar = lower_helper(&Session::test(), grammar, true).unwrap();
    assert!(inline_order(&grammar).is_err());
}

#[test]
fn test_inline_order() {
    // because C references A, we inline A first.
    let grammar = parser::parse_grammar(
        r#"
    grammar;
    extern { }
    #[inline] A: () = B;
    B: () = C;
    #[inline] C: () = A;
"#,
    )
    .unwrap();
    let grammar = lower_helper(&Session::test(), grammar, true).unwrap();
    let a = NonterminalString(Atom::from("A"));
    let c = NonterminalString(Atom::from("C"));
    assert_eq!(inline_order(&grammar).unwrap(), vec![a, c]);
}