aboutsummaryrefslogtreecommitdiff
path: root/crates/base_db/src/input.rs
blob: 64ccd11eec8ab18032ede9c9a6ab9acf3f9d97d5 (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
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
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
//! This module specifies the input to rust-analyzer. In some sense, this is
//! **the** most important module, because all other fancy stuff is strictly
//! derived from this input.
//!
//! Note that neither this module, nor any other part of the analyzer's core do
//! actual IO. See `vfs` and `project_model` in the `rust-analyzer` crate for how
//! actual IO is done and lowered to input.

use std::{fmt, iter::FromIterator, ops, panic::RefUnwindSafe, str::FromStr, sync::Arc};

use cfg::CfgOptions;
use rustc_hash::{FxHashMap, FxHashSet};
use syntax::SmolStr;
use tt::{ExpansionError, Subtree};
use vfs::{file_set::FileSet, FileId, VfsPath};

/// Files are grouped into source roots. A source root is a directory on the
/// file systems which is watched for changes. Typically it corresponds to a
/// Rust crate. Source roots *might* be nested: in this case, a file belongs to
/// the nearest enclosing source root. Paths to files are always relative to a
/// source root, and the analyzer does not know the root path of the source root at
/// all. So, a file from one source root can't refer to a file in another source
/// root by path.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
pub struct SourceRootId(pub u32);

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct SourceRoot {
    /// Sysroot or crates.io library.
    ///
    /// Libraries are considered mostly immutable, this assumption is used to
    /// optimize salsa's query structure
    pub is_library: bool,
    pub(crate) file_set: FileSet,
}

impl SourceRoot {
    pub fn new_local(file_set: FileSet) -> SourceRoot {
        SourceRoot { is_library: false, file_set }
    }
    pub fn new_library(file_set: FileSet) -> SourceRoot {
        SourceRoot { is_library: true, file_set }
    }
    pub fn path_for_file(&self, file: &FileId) -> Option<&VfsPath> {
        self.file_set.path_for_file(file)
    }
    pub fn file_for_path(&self, path: &VfsPath) -> Option<&FileId> {
        self.file_set.file_for_path(path)
    }
    pub fn iter(&self) -> impl Iterator<Item = FileId> + '_ {
        self.file_set.iter()
    }
}

/// `CrateGraph` is a bit of information which turns a set of text files into a
/// number of Rust crates.
///
/// Each crate is defined by the `FileId` of its root module, the set of enabled
/// `cfg` flags and the set of dependencies.
///
/// Note that, due to cfg's, there might be several crates for a single `FileId`!
///
/// For the purposes of analysis, a crate does not have a name. Instead, names
/// are specified on dependency edges. That is, a crate might be known under
/// different names in different dependent crates.
///
/// Note that `CrateGraph` is build-system agnostic: it's a concept of the Rust
/// language proper, not a concept of the build system. In practice, we get
/// `CrateGraph` by lowering `cargo metadata` output.
#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub struct CrateGraph {
    arena: FxHashMap<CrateId, CrateData>,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct CrateId(pub u32);

#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct CrateName(SmolStr);

impl CrateName {
    /// Creates a crate name, checking for dashes in the string provided.
    /// Dashes are not allowed in the crate names,
    /// hence the input string is returned as `Err` for those cases.
    pub fn new(name: &str) -> Result<CrateName, &str> {
        if name.contains('-') {
            Err(name)
        } else {
            Ok(Self(SmolStr::new(name)))
        }
    }

    /// Creates a crate name, unconditionally replacing the dashes with underscores.
    pub fn normalize_dashes(name: &str) -> CrateName {
        Self(SmolStr::new(name.replace('-', "_")))
    }
}

impl fmt::Display for CrateName {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}", self.0)
    }
}

impl ops::Deref for CrateName {
    type Target = str;
    fn deref(&self) -> &str {
        &*self.0
    }
}

#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct CrateDisplayName {
    // The name we use to display various paths (with `_`).
    crate_name: CrateName,
    // The name as specified in Cargo.toml (with `-`).
    canonical_name: String,
}

impl From<CrateName> for CrateDisplayName {
    fn from(crate_name: CrateName) -> CrateDisplayName {
        let canonical_name = crate_name.to_string();
        CrateDisplayName { crate_name, canonical_name }
    }
}

impl fmt::Display for CrateDisplayName {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}", self.crate_name)
    }
}

impl ops::Deref for CrateDisplayName {
    type Target = str;
    fn deref(&self) -> &str {
        &*self.crate_name
    }
}

impl CrateDisplayName {
    pub fn from_canonical_name(canonical_name: String) -> CrateDisplayName {
        let crate_name = CrateName::normalize_dashes(&canonical_name);
        CrateDisplayName { crate_name, canonical_name }
    }
}

#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub struct ProcMacroId(pub u32);

#[derive(Copy, Clone, Eq, PartialEq, Debug)]
pub enum ProcMacroKind {
    CustomDerive,
    FuncLike,
    Attr,
}

pub trait ProcMacroExpander: fmt::Debug + Send + Sync + RefUnwindSafe {
    fn expand(
        &self,
        subtree: &Subtree,
        attrs: Option<&Subtree>,
        env: &Env,
    ) -> Result<Subtree, ExpansionError>;
}

#[derive(Debug, Clone)]
pub struct ProcMacro {
    pub name: SmolStr,
    pub kind: ProcMacroKind,
    pub expander: Arc<dyn ProcMacroExpander>,
}

impl Eq for ProcMacro {}
impl PartialEq for ProcMacro {
    fn eq(&self, other: &ProcMacro) -> bool {
        self.name == other.name && Arc::ptr_eq(&self.expander, &other.expander)
    }
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct CrateData {
    pub root_file_id: FileId,
    pub edition: Edition,
    /// A name used in the package's project declaration: for Cargo projects,
    /// its `[package].name` can be different for other project types or even
    /// absent (a dummy crate for the code snippet, for example).
    ///
    /// For purposes of analysis, crates are anonymous (only names in
    /// `Dependency` matters), this name should only be used for UI.
    pub display_name: Option<CrateDisplayName>,
    pub cfg_options: CfgOptions,
    pub env: Env,
    pub dependencies: Vec<Dependency>,
    pub proc_macro: Vec<ProcMacro>,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum Edition {
    Edition2015,
    Edition2018,
    Edition2021,
}

#[derive(Default, Debug, Clone, PartialEq, Eq)]
pub struct Env {
    entries: FxHashMap<String, String>,
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct Dependency {
    pub crate_id: CrateId,
    pub name: CrateName,
}

impl CrateGraph {
    pub fn add_crate_root(
        &mut self,
        file_id: FileId,
        edition: Edition,
        display_name: Option<CrateDisplayName>,
        cfg_options: CfgOptions,
        env: Env,
        proc_macro: Vec<ProcMacro>,
    ) -> CrateId {
        let data = CrateData {
            root_file_id: file_id,
            edition,
            display_name,
            cfg_options,
            env,
            proc_macro,
            dependencies: Vec::new(),
        };
        let crate_id = CrateId(self.arena.len() as u32);
        let prev = self.arena.insert(crate_id, data);
        assert!(prev.is_none());
        crate_id
    }

    pub fn add_dep(
        &mut self,
        from: CrateId,
        name: CrateName,
        to: CrateId,
    ) -> Result<(), CyclicDependenciesError> {
        let _p = profile::span("add_dep");
        if self.dfs_find(from, to, &mut FxHashSet::default()) {
            return Err(CyclicDependenciesError {
                from: (from, self[from].display_name.clone()),
                to: (to, self[to].display_name.clone()),
            });
        }
        self.arena.get_mut(&from).unwrap().add_dep(name, to);
        Ok(())
    }

    pub fn is_empty(&self) -> bool {
        self.arena.is_empty()
    }

    pub fn iter(&self) -> impl Iterator<Item = CrateId> + '_ {
        self.arena.keys().copied()
    }

    /// Returns an iterator over all transitive dependencies of the given crate,
    /// including the crate itself.
    pub fn transitive_deps(&self, of: CrateId) -> impl Iterator<Item = CrateId> + '_ {
        let mut worklist = vec![of];
        let mut deps = FxHashSet::default();

        while let Some(krate) = worklist.pop() {
            if !deps.insert(krate) {
                continue;
            }

            worklist.extend(self[krate].dependencies.iter().map(|dep| dep.crate_id));
        }

        deps.into_iter()
    }

    /// Returns all transitive reverse dependencies of the given crate,
    /// including the crate itself.
    pub fn transitive_rev_deps(&self, of: CrateId) -> impl Iterator<Item = CrateId> + '_ {
        let mut worklist = vec![of];
        let mut rev_deps = FxHashSet::default();
        rev_deps.insert(of);

        let mut inverted_graph = FxHashMap::<_, Vec<_>>::default();
        self.arena.iter().for_each(|(&krate, data)| {
            data.dependencies
                .iter()
                .for_each(|dep| inverted_graph.entry(dep.crate_id).or_default().push(krate))
        });

        while let Some(krate) = worklist.pop() {
            if let Some(krate_rev_deps) = inverted_graph.get(&krate) {
                krate_rev_deps
                    .iter()
                    .copied()
                    .filter(|&rev_dep| rev_deps.insert(rev_dep))
                    .for_each(|rev_dep| worklist.push(rev_dep));
            }
        }

        rev_deps.into_iter()
    }

    /// Returns all crates in the graph, sorted in topological order (ie. dependencies of a crate
    /// come before the crate itself).
    pub fn crates_in_topological_order(&self) -> Vec<CrateId> {
        let mut res = Vec::new();
        let mut visited = FxHashSet::default();

        for krate in self.arena.keys().copied() {
            go(self, &mut visited, &mut res, krate);
        }

        return res;

        fn go(
            graph: &CrateGraph,
            visited: &mut FxHashSet<CrateId>,
            res: &mut Vec<CrateId>,
            source: CrateId,
        ) {
            if !visited.insert(source) {
                return;
            }
            for dep in graph[source].dependencies.iter() {
                go(graph, visited, res, dep.crate_id)
            }
            res.push(source)
        }
    }

    // FIXME: this only finds one crate with the given root; we could have multiple
    pub fn crate_id_for_crate_root(&self, file_id: FileId) -> Option<CrateId> {
        let (&crate_id, _) =
            self.arena.iter().find(|(_crate_id, data)| data.root_file_id == file_id)?;
        Some(crate_id)
    }

    /// Extends this crate graph by adding a complete disjoint second crate
    /// graph.
    ///
    /// The ids of the crates in the `other` graph are shifted by the return
    /// amount.
    pub fn extend(&mut self, other: CrateGraph) -> u32 {
        let start = self.arena.len() as u32;
        self.arena.extend(other.arena.into_iter().map(|(id, mut data)| {
            let new_id = id.shift(start);
            for dep in &mut data.dependencies {
                dep.crate_id = dep.crate_id.shift(start);
            }
            (new_id, data)
        }));
        start
    }

    fn dfs_find(&self, target: CrateId, from: CrateId, visited: &mut FxHashSet<CrateId>) -> bool {
        if !visited.insert(from) {
            return false;
        }

        if target == from {
            return true;
        }

        for dep in &self[from].dependencies {
            let crate_id = dep.crate_id;
            if self.dfs_find(target, crate_id, visited) {
                return true;
            }
        }
        false
    }

    // Work around for https://github.com/rust-analyzer/rust-analyzer/issues/6038.
    // As hacky as it gets.
    pub fn patch_cfg_if(&mut self) -> bool {
        let cfg_if = self.hacky_find_crate("cfg_if");
        let std = self.hacky_find_crate("std");
        match (cfg_if, std) {
            (Some(cfg_if), Some(std)) => {
                self.arena.get_mut(&cfg_if).unwrap().dependencies.clear();
                self.arena
                    .get_mut(&std)
                    .unwrap()
                    .dependencies
                    .push(Dependency { crate_id: cfg_if, name: CrateName::new("cfg_if").unwrap() });
                true
            }
            _ => false,
        }
    }

    fn hacky_find_crate(&self, display_name: &str) -> Option<CrateId> {
        self.iter().find(|it| self[*it].display_name.as_deref() == Some(display_name))
    }
}

impl ops::Index<CrateId> for CrateGraph {
    type Output = CrateData;
    fn index(&self, crate_id: CrateId) -> &CrateData {
        &self.arena[&crate_id]
    }
}

impl CrateId {
    pub fn shift(self, amount: u32) -> CrateId {
        CrateId(self.0 + amount)
    }
}

impl CrateData {
    fn add_dep(&mut self, name: CrateName, crate_id: CrateId) {
        self.dependencies.push(Dependency { crate_id, name })
    }
}

impl FromStr for Edition {
    type Err = ParseEditionError;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let res = match s {
            "2015" => Edition::Edition2015,
            "2018" => Edition::Edition2018,
            "2021" => Edition::Edition2021,
            _ => return Err(ParseEditionError { invalid_input: s.to_string() }),
        };
        Ok(res)
    }
}

impl fmt::Display for Edition {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_str(match self {
            Edition::Edition2015 => "2015",
            Edition::Edition2018 => "2018",
            Edition::Edition2021 => "2021",
        })
    }
}

impl FromIterator<(String, String)> for Env {
    fn from_iter<T: IntoIterator<Item = (String, String)>>(iter: T) -> Self {
        Env { entries: FromIterator::from_iter(iter) }
    }
}

impl Env {
    pub fn set(&mut self, env: &str, value: String) {
        self.entries.insert(env.to_owned(), value);
    }

    pub fn get(&self, env: &str) -> Option<String> {
        self.entries.get(env).cloned()
    }

    pub fn iter(&self) -> impl Iterator<Item = (&str, &str)> {
        self.entries.iter().map(|(k, v)| (k.as_str(), v.as_str()))
    }
}

#[derive(Debug)]
pub struct ParseEditionError {
    invalid_input: String,
}

impl fmt::Display for ParseEditionError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "invalid edition: {:?}", self.invalid_input)
    }
}

impl std::error::Error for ParseEditionError {}

#[derive(Debug)]
pub struct CyclicDependenciesError {
    from: (CrateId, Option<CrateDisplayName>),
    to: (CrateId, Option<CrateDisplayName>),
}

impl fmt::Display for CyclicDependenciesError {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let render = |(id, name): &(CrateId, Option<CrateDisplayName>)| match name {
            Some(it) => format!("{}({:?})", it, id),
            None => format!("{:?}", id),
        };
        write!(f, "cyclic deps: {} -> {}", render(&self.from), render(&self.to))
    }
}

#[cfg(test)]
mod tests {
    use super::{CfgOptions, CrateGraph, CrateName, Dependency, Edition::Edition2018, Env, FileId};

    #[test]
    fn detect_cyclic_dependency_indirect() {
        let mut graph = CrateGraph::default();
        let crate1 = graph.add_crate_root(
            FileId(1u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        let crate2 = graph.add_crate_root(
            FileId(2u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        let crate3 = graph.add_crate_root(
            FileId(3u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        assert!(graph.add_dep(crate1, CrateName::new("crate2").unwrap(), crate2).is_ok());
        assert!(graph.add_dep(crate2, CrateName::new("crate3").unwrap(), crate3).is_ok());
        assert!(graph.add_dep(crate3, CrateName::new("crate1").unwrap(), crate1).is_err());
    }

    #[test]
    fn detect_cyclic_dependency_direct() {
        let mut graph = CrateGraph::default();
        let crate1 = graph.add_crate_root(
            FileId(1u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        let crate2 = graph.add_crate_root(
            FileId(2u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        assert!(graph.add_dep(crate1, CrateName::new("crate2").unwrap(), crate2).is_ok());
        assert!(graph.add_dep(crate2, CrateName::new("crate2").unwrap(), crate2).is_err());
    }

    #[test]
    fn it_works() {
        let mut graph = CrateGraph::default();
        let crate1 = graph.add_crate_root(
            FileId(1u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        let crate2 = graph.add_crate_root(
            FileId(2u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        let crate3 = graph.add_crate_root(
            FileId(3u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        assert!(graph.add_dep(crate1, CrateName::new("crate2").unwrap(), crate2).is_ok());
        assert!(graph.add_dep(crate2, CrateName::new("crate3").unwrap(), crate3).is_ok());
    }

    #[test]
    fn dashes_are_normalized() {
        let mut graph = CrateGraph::default();
        let crate1 = graph.add_crate_root(
            FileId(1u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        let crate2 = graph.add_crate_root(
            FileId(2u32),
            Edition2018,
            None,
            CfgOptions::default(),
            Env::default(),
            Default::default(),
        );
        assert!(graph
            .add_dep(crate1, CrateName::normalize_dashes("crate-name-with-dashes"), crate2)
            .is_ok());
        assert_eq!(
            graph[crate1].dependencies,
            vec![Dependency {
                crate_id: crate2,
                name: CrateName::new("crate_name_with_dashes").unwrap()
            }]
        );
    }
}