xtask/codegen/
parser_inline_tests.rs

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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
//! This module greps parser's code for specially formatted comments and turns
//! them into tests.
#![allow(clippy::disallowed_types, clippy::print_stdout)]

use std::{
    collections::HashMap,
    fs, iter,
    path::{Path, PathBuf},
    time::SystemTime,
};

use anyhow::Result;
use itertools::Itertools as _;

use crate::{
    codegen::{ensure_file_contents, reformat, CommentBlock},
    project_root,
    util::list_rust_files,
};

const PARSER_CRATE_ROOT: &str = "crates/parser";
const PARSER_TEST_DATA: &str = "crates/parser/test_data";
const PARSER_TEST_DATA_INLINE: &str = "crates/parser/test_data/parser/inline";

pub(crate) fn generate(check: bool) {
    let tests = tests_from_dir(
        &project_root().join(Path::new(&format!("{PARSER_CRATE_ROOT}/src/grammar"))),
    );

    let mut some_file_was_updated = false;
    some_file_was_updated |=
        install_tests(&tests.ok, &format!("{PARSER_TEST_DATA_INLINE}/ok"), check).unwrap();
    some_file_was_updated |=
        install_tests(&tests.err, &format!("{PARSER_TEST_DATA_INLINE}/err"), check).unwrap();

    if some_file_was_updated {
        let _ = fs::File::open(format!("{PARSER_CRATE_ROOT}/src/tests.rs"))
            .unwrap()
            .set_modified(SystemTime::now());

        let ok_tests = tests.ok.values().sorted_by(|a, b| a.name.cmp(&b.name)).map(|test| {
            let test_name = quote::format_ident!("{}", test.name);
            let test_file = format!("test_data/parser/inline/ok/{test_name}.rs");
            let (test_func, args) = match &test.edition {
                Some(edition) => {
                    let edition = quote::format_ident!("Edition{edition}");
                    (
                        quote::format_ident!("run_and_expect_no_errors_with_edition"),
                        quote::quote! {#test_file, crate::Edition::#edition},
                    )
                }
                None => {
                    (quote::format_ident!("run_and_expect_no_errors"), quote::quote! {#test_file})
                }
            };
            quote::quote! {
                #[test]
                fn #test_name() {
                    #test_func(#args);
                }
            }
        });
        let err_tests = tests.err.values().sorted_by(|a, b| a.name.cmp(&b.name)).map(|test| {
            let test_name = quote::format_ident!("{}", test.name);
            let test_file = format!("test_data/parser/inline/err/{test_name}.rs");
            let (test_func, args) = match &test.edition {
                Some(edition) => {
                    let edition = quote::format_ident!("Edition{edition}");
                    (
                        quote::format_ident!("run_and_expect_errors_with_edition"),
                        quote::quote! {#test_file, crate::Edition::#edition},
                    )
                }
                None => (quote::format_ident!("run_and_expect_errors"), quote::quote! {#test_file}),
            };
            quote::quote! {
                #[test]
                fn #test_name() {
                    #test_func(#args);
                }
            }
        });

        let output = quote::quote! {
            mod ok {
                use crate::tests::*;
                #(#ok_tests)*
            }
            mod err {
                use crate::tests::*;
                #(#err_tests)*
            }
        };

        let pretty = reformat(output.to_string());
        ensure_file_contents(
            crate::flags::CodegenType::ParserTests,
            format!("{PARSER_TEST_DATA}/generated/runner.rs").as_ref(),
            &pretty,
            check,
        );
    }
}

fn install_tests(tests: &HashMap<String, Test>, into: &str, check: bool) -> Result<bool> {
    let tests_dir = project_root().join(into);
    if !tests_dir.is_dir() {
        fs::create_dir_all(&tests_dir)?;
    }
    let existing = existing_tests(&tests_dir, TestKind::Ok)?;
    if let Some((t, (path, _))) = existing.iter().find(|&(t, _)| !tests.contains_key(t)) {
        panic!("Test `{t}` is deleted: {}", path.display());
    }

    let mut some_file_was_updated = false;

    for (name, test) in tests {
        let path = match existing.get(name) {
            Some((path, _test)) => path.clone(),
            None => tests_dir.join(name).with_extension("rs"),
        };
        if ensure_file_contents(crate::flags::CodegenType::ParserTests, &path, &test.text, check) {
            some_file_was_updated = true;
        }
    }

    Ok(some_file_was_updated)
}

#[derive(Debug)]
struct Test {
    name: String,
    text: String,
    kind: TestKind,
    edition: Option<String>,
}

#[derive(Copy, Clone, Debug)]
enum TestKind {
    Ok,
    Err,
}

#[derive(Default, Debug)]
struct Tests {
    ok: HashMap<String, Test>,
    err: HashMap<String, Test>,
}

fn collect_tests(s: &str) -> Vec<Test> {
    let mut res = Vec::new();
    for comment_block in CommentBlock::extract_untagged(s) {
        let first_line = &comment_block.contents[0];
        let (name, kind) = if let Some(name) = first_line.strip_prefix("test ") {
            (name.to_owned(), TestKind::Ok)
        } else if let Some(name) = first_line.strip_prefix("test_err ") {
            (name.to_owned(), TestKind::Err)
        } else {
            continue;
        };
        let (name, edition) = match *name.split(' ').collect_vec().as_slice() {
            [name, edition] => {
                assert!(!edition.contains(' '));
                (name.to_owned(), Some(edition.to_owned()))
            }
            [name] => (name.to_owned(), None),
            _ => panic!("invalid test name: {:?}", name),
        };
        let text: String = edition
            .as_ref()
            .map(|edition| format!("// {edition}"))
            .into_iter()
            .chain(comment_block.contents[1..].iter().cloned())
            .chain(iter::once(String::new()))
            .collect::<Vec<_>>()
            .join("\n");
        assert!(!text.trim().is_empty() && text.ends_with('\n'));
        res.push(Test { name, edition, text, kind })
    }
    res
}

fn tests_from_dir(dir: &Path) -> Tests {
    let mut res = Tests::default();
    for entry in list_rust_files(dir) {
        process_file(&mut res, entry.as_path());
    }
    let grammar_rs = dir.parent().unwrap().join("grammar.rs");
    process_file(&mut res, &grammar_rs);
    return res;

    fn process_file(res: &mut Tests, path: &Path) {
        let text = fs::read_to_string(path).unwrap();

        for test in collect_tests(&text) {
            if let TestKind::Ok = test.kind {
                if let Some(old_test) = res.ok.insert(test.name.clone(), test) {
                    panic!("Duplicate test: {}", old_test.name);
                }
            } else if let Some(old_test) = res.err.insert(test.name.clone(), test) {
                panic!("Duplicate test: {}", old_test.name);
            }
        }
    }
}

fn existing_tests(dir: &Path, ok: TestKind) -> Result<HashMap<String, (PathBuf, Test)>> {
    let mut res = HashMap::new();
    for file in fs::read_dir(dir)? {
        let path = file?.path();
        let rust_file = path.extension().and_then(|ext| ext.to_str()) == Some("rs");

        if rust_file {
            let name = path.file_stem().map(|x| x.to_string_lossy().to_string()).unwrap();
            let text = fs::read_to_string(&path)?;
            let edition =
                text.lines().next().and_then(|it| it.strip_prefix("// ")).map(ToOwned::to_owned);
            let test = Test { name: name.clone(), text, kind: ok, edition };
            if let Some(old) = res.insert(name, (path, test)) {
                println!("Duplicate test: {:?}", old);
            }
        }
    }
    Ok(res)
}

#[test]
fn test() {
    generate(true);
}