aboutsummaryrefslogtreecommitdiff
path: root/src/parser/grammar/mod.rs
blob: 54a63a5474f28caf137bd7d912d9831d13563c42 (plain)
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
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
//! This is the actual "grammar" of the Rust language.
//!
//! Each function in this module and its children corresponds
//! to a production of the format grammar. Submodules roughly
//! correspond to different *areas* of the grammar. By convention,
//! each submodule starts with `use super::*` import and exports
//! "public" productions via `pub(super)`.
//!
//! See docs for `Parser` to learn about API, available to the grammar,
//! and see docs for `Event` to learn how this actually manages to
//! produce parse trees.
//!
//! Code in this module also contains inline tests, which start with
//! `// test name-of-the-test` comment and look like this:
//!
//! ```
//! // test fn_item_with_zero_parameters
//! // fn foo() {}
//! ```
//!
//! After adding a new inline-test, run `cargo collect-tests` to extract
//! it as a standalone text-fixture into `tests/data/parser/inline`, and
//! run `cargo test` once to create the "gold" value.
use parser::parser::Parser;
use parser::token_set::TokenSet;
use SyntaxKind;
use syntax_kinds::*;

mod items;
mod attributes;
mod expressions;
mod types;
mod patterns;
mod paths;
mod type_params;

pub(crate) fn file(p: &mut Parser) {
    let file = p.start();
    p.eat(SHEBANG);
    items::mod_contents(p, false);
    file.complete(p, FILE);
}

fn visibility(p: &mut Parser) {
    if p.at(PUB_KW) {
        let vis = p.start();
        p.bump();
        if p.at(L_PAREN) {
            match p.nth(1) {
                CRATE_KW | SELF_KW | SUPER_KW => {
                    p.bump();
                    p.bump();
                    p.expect(R_PAREN);
                }
                IN_KW => {
                    p.bump();
                    p.bump();
                    paths::use_path(p);
                    p.expect(R_PAREN);
                }
                _ => (),
            }
        }
        vis.complete(p, VISIBILITY);
    }
}

fn alias(p: &mut Parser) -> bool {
    if p.at(AS_KW) {
        let alias = p.start();
        p.bump();
        name(p);
        alias.complete(p, ALIAS);
    }
    true //FIXME: return false if three are errors
}

fn abi(p: &mut Parser) {
    assert!(p.at(EXTERN_KW));
    let abi = p.start();
    p.bump();
    match p.current() {
        STRING | RAW_STRING => p.bump(),
        _ => (),
    }
    abi.complete(p, ABI);
}

// test fn_value_parameters
// fn a() {}
// fn b(x: i32) {}
// fn c(x: i32, ) {}
// fn d(x: i32, y: ()) {}
fn fn_value_parameters(p: &mut Parser) {
    assert!(p.at(L_PAREN));
    p.bump();
    while !p.at(EOF) && !p.at(R_PAREN) {
        value_parameter(p);
        if !p.at(R_PAREN) {
            p.expect(COMMA);
        }
    }
    p.expect(R_PAREN);

    fn value_parameter(p: &mut Parser) {
        let m = p.start();
        patterns::pattern(p);
        p.expect(COLON);
        types::type_(p);
        m.complete(p, VALUE_PARAMETER);
    }
}

fn fn_ret_type(p: &mut Parser) {
    if p.at(THIN_ARROW) {
        p.bump();
        types::type_(p);
    }
}

fn name(p: &mut Parser) {
    if p.at(IDENT) {
        let m = p.start();
        p.bump();
        m.complete(p, NAME);
    } else {
        p.error("expected a name");
    }
}

fn name_ref(p: &mut Parser) {
    if p.at(IDENT) {
        let m = p.start();
        p.bump();
        m.complete(p, NAME_REF);
    } else {
        p.error("expected identifier");
    }
}

fn error_block(p: &mut Parser, message: &str) {
    assert!(p.at(L_CURLY));
    let err = p.start();
    p.error(message);
    p.bump();
    let mut level: u32 = 1;
    while level > 0 && !p.at(EOF) {
        match p.current() {
            L_CURLY => level += 1,
            R_CURLY => level -= 1,
            _ => (),
        }
        p.bump();
    }
    err.complete(p, ERROR);
}