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
|
pub(crate) mod lower;
pub(crate) mod scope;
pub(crate) mod validation;
use std::{ops::Index, sync::Arc};
use ra_arena::{impl_arena_id, map::ArenaMap, Arena, RawId};
use ra_syntax::{ast, AstPtr};
use rustc_hash::FxHashMap;
use crate::{
db::HirDatabase,
path::GenericArgs,
ty::primitive::{UncertainFloatTy, UncertainIntTy},
type_ref::{Mutability, TypeRef},
DefWithBody, Either, HasSource, Name, Path, Resolver, Source,
};
pub use self::scope::ExprScopes;
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct ExprId(RawId);
impl_arena_id!(ExprId);
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct PatId(RawId);
impl_arena_id!(PatId);
/// The body of an item (function, const etc.).
#[derive(Debug, Eq, PartialEq)]
pub struct Body {
/// The def of the item this body belongs to
owner: DefWithBody,
exprs: Arena<ExprId, Expr>,
pats: Arena<PatId, Pat>,
/// The patterns for the function's parameters. While the parameter types are
/// part of the function signature, the patterns are not (they don't change
/// the external type of the function).
///
/// If this `Body` is for the body of a constant, this will just be
/// empty.
params: Vec<PatId>,
/// The `ExprId` of the actual body expression.
body_expr: ExprId,
}
type ExprPtr = Either<AstPtr<ast::Expr>, AstPtr<ast::RecordField>>;
type ExprSource = Source<ExprPtr>;
type PatPtr = Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>>;
type PatSource = Source<PatPtr>;
/// An item body together with the mapping from syntax nodes to HIR expression
/// IDs. This is needed to go from e.g. a position in a file to the HIR
/// expression containing it; but for type inference etc., we want to operate on
/// a structure that is agnostic to the actual positions of expressions in the
/// file, so that we don't recompute types whenever some whitespace is typed.
///
/// One complication here is that, due to macro expansion, a single `Body` might
/// be spread across several files. So, for each ExprId and PatId, we record
/// both the HirFileId and the position inside the file. However, we only store
/// AST -> ExprId mapping for non-macro files, as it is not clear how to handle
/// this properly for macros.
#[derive(Default, Debug, Eq, PartialEq)]
pub struct BodySourceMap {
expr_map: FxHashMap<ExprPtr, ExprId>,
expr_map_back: ArenaMap<ExprId, ExprSource>,
pat_map: FxHashMap<PatPtr, PatId>,
pat_map_back: ArenaMap<PatId, PatSource>,
field_map: FxHashMap<(ExprId, usize), AstPtr<ast::RecordField>>,
}
impl Body {
pub fn params(&self) -> &[PatId] {
&self.params
}
pub fn body_expr(&self) -> ExprId {
self.body_expr
}
pub fn owner(&self) -> DefWithBody {
self.owner
}
pub fn exprs(&self) -> impl Iterator<Item = (ExprId, &Expr)> {
self.exprs.iter()
}
pub fn pats(&self) -> impl Iterator<Item = (PatId, &Pat)> {
self.pats.iter()
}
}
// needs arbitrary_self_types to be a method... or maybe move to the def?
pub(crate) fn resolver_for_expr(
body: Arc<Body>,
db: &impl HirDatabase,
expr_id: ExprId,
) -> Resolver {
let scopes = db.expr_scopes(body.owner);
resolver_for_scope(body, db, scopes.scope_for(expr_id))
}
pub(crate) fn resolver_for_scope(
body: Arc<Body>,
db: &impl HirDatabase,
scope_id: Option<scope::ScopeId>,
) -> Resolver {
let mut r = body.owner.resolver(db);
let scopes = db.expr_scopes(body.owner);
let scope_chain = scopes.scope_chain(scope_id).collect::<Vec<_>>();
for scope in scope_chain.into_iter().rev() {
r = r.push_expr_scope(Arc::clone(&scopes), scope);
}
r
}
impl Index<ExprId> for Body {
type Output = Expr;
fn index(&self, expr: ExprId) -> &Expr {
&self.exprs[expr]
}
}
impl Index<PatId> for Body {
type Output = Pat;
fn index(&self, pat: PatId) -> &Pat {
&self.pats[pat]
}
}
impl BodySourceMap {
pub(crate) fn expr_syntax(&self, expr: ExprId) -> Option<ExprSource> {
self.expr_map_back.get(expr).copied()
}
pub(crate) fn node_expr(&self, node: &ast::Expr) -> Option<ExprId> {
self.expr_map.get(&Either::A(AstPtr::new(node))).cloned()
}
pub(crate) fn pat_syntax(&self, pat: PatId) -> Option<PatSource> {
self.pat_map_back.get(pat).copied()
}
pub(crate) fn node_pat(&self, node: &ast::Pat) -> Option<PatId> {
self.pat_map.get(&Either::A(AstPtr::new(node))).cloned()
}
pub(crate) fn field_syntax(&self, expr: ExprId, field: usize) -> AstPtr<ast::RecordField> {
self.field_map[&(expr, field)]
}
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum Literal {
String(String),
ByteString(Vec<u8>),
Char(char),
Bool(bool),
Int(u64, UncertainIntTy),
Float(u64, UncertainFloatTy), // FIXME: f64 is not Eq
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum Expr {
/// This is produced if syntax tree does not have a required expression piece.
Missing,
Path(Path),
If {
condition: ExprId,
then_branch: ExprId,
else_branch: Option<ExprId>,
},
Block {
statements: Vec<Statement>,
tail: Option<ExprId>,
},
Loop {
body: ExprId,
},
While {
condition: ExprId,
body: ExprId,
},
For {
iterable: ExprId,
pat: PatId,
body: ExprId,
},
Call {
callee: ExprId,
args: Vec<ExprId>,
},
MethodCall {
receiver: ExprId,
method_name: Name,
args: Vec<ExprId>,
generic_args: Option<GenericArgs>,
},
Match {
expr: ExprId,
arms: Vec<MatchArm>,
},
Continue,
Break {
expr: Option<ExprId>,
},
Return {
expr: Option<ExprId>,
},
RecordLit {
path: Option<Path>,
fields: Vec<RecordLitField>,
spread: Option<ExprId>,
},
Field {
expr: ExprId,
name: Name,
},
Await {
expr: ExprId,
},
Try {
expr: ExprId,
},
TryBlock {
body: ExprId,
},
Cast {
expr: ExprId,
type_ref: TypeRef,
},
Ref {
expr: ExprId,
mutability: Mutability,
},
UnaryOp {
expr: ExprId,
op: UnaryOp,
},
BinaryOp {
lhs: ExprId,
rhs: ExprId,
op: Option<BinaryOp>,
},
Index {
base: ExprId,
index: ExprId,
},
Lambda {
args: Vec<PatId>,
arg_types: Vec<Option<TypeRef>>,
body: ExprId,
},
Tuple {
exprs: Vec<ExprId>,
},
Array(Array),
Literal(Literal),
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum BinaryOp {
LogicOp(LogicOp),
ArithOp(ArithOp),
CmpOp(CmpOp),
Assignment { op: Option<ArithOp> },
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum LogicOp {
And,
Or,
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum CmpOp {
Eq { negated: bool },
Ord { ordering: Ordering, strict: bool },
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum Ordering {
Less,
Greater,
}
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum ArithOp {
Add,
Mul,
Sub,
Div,
Rem,
Shl,
Shr,
BitXor,
BitOr,
BitAnd,
}
pub use ra_syntax::ast::PrefixOp as UnaryOp;
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum Array {
ElementList(Vec<ExprId>),
Repeat { initializer: ExprId, repeat: ExprId },
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub struct MatchArm {
pub pats: Vec<PatId>,
pub guard: Option<ExprId>,
pub expr: ExprId,
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub struct RecordLitField {
pub name: Name,
pub expr: ExprId,
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum Statement {
Let { pat: PatId, type_ref: Option<TypeRef>, initializer: Option<ExprId> },
Expr(ExprId),
}
impl Expr {
pub fn walk_child_exprs(&self, mut f: impl FnMut(ExprId)) {
match self {
Expr::Missing => {}
Expr::Path(_) => {}
Expr::If { condition, then_branch, else_branch } => {
f(*condition);
f(*then_branch);
if let Some(else_branch) = else_branch {
f(*else_branch);
}
}
Expr::Block { statements, tail } => {
for stmt in statements {
match stmt {
Statement::Let { initializer, .. } => {
if let Some(expr) = initializer {
f(*expr);
}
}
Statement::Expr(e) => f(*e),
}
}
if let Some(expr) = tail {
f(*expr);
}
}
Expr::TryBlock { body } => f(*body),
Expr::Loop { body } => f(*body),
Expr::While { condition, body } => {
f(*condition);
f(*body);
}
Expr::For { iterable, body, .. } => {
f(*iterable);
f(*body);
}
Expr::Call { callee, args } => {
f(*callee);
for arg in args {
f(*arg);
}
}
Expr::MethodCall { receiver, args, .. } => {
f(*receiver);
for arg in args {
f(*arg);
}
}
Expr::Match { expr, arms } => {
f(*expr);
for arm in arms {
f(arm.expr);
}
}
Expr::Continue => {}
Expr::Break { expr } | Expr::Return { expr } => {
if let Some(expr) = expr {
f(*expr);
}
}
Expr::RecordLit { fields, spread, .. } => {
for field in fields {
f(field.expr);
}
if let Some(expr) = spread {
f(*expr);
}
}
Expr::Lambda { body, .. } => {
f(*body);
}
Expr::BinaryOp { lhs, rhs, .. } => {
f(*lhs);
f(*rhs);
}
Expr::Index { base, index } => {
f(*base);
f(*index);
}
Expr::Field { expr, .. }
| Expr::Await { expr }
| Expr::Try { expr }
| Expr::Cast { expr, .. }
| Expr::Ref { expr, .. }
| Expr::UnaryOp { expr, .. } => {
f(*expr);
}
Expr::Tuple { exprs } => {
for expr in exprs {
f(*expr);
}
}
Expr::Array(a) => match a {
Array::ElementList(exprs) => {
for expr in exprs {
f(*expr);
}
}
Array::Repeat { initializer, repeat } => {
f(*initializer);
f(*repeat)
}
},
Expr::Literal(_) => {}
}
}
}
/// Explicit binding annotations given in the HIR for a binding. Note
/// that this is not the final binding *mode* that we infer after type
/// inference.
#[derive(Clone, PartialEq, Eq, Debug, Copy)]
pub enum BindingAnnotation {
/// No binding annotation given: this means that the final binding mode
/// will depend on whether we have skipped through a `&` reference
/// when matching. For example, the `x` in `Some(x)` will have binding
/// mode `None`; if you do `let Some(x) = &Some(22)`, it will
/// ultimately be inferred to be by-reference.
Unannotated,
/// Annotated with `mut x` -- could be either ref or not, similar to `None`.
Mutable,
/// Annotated as `ref`, like `ref x`
Ref,
/// Annotated as `ref mut x`.
RefMut,
}
impl BindingAnnotation {
fn new(is_mutable: bool, is_ref: bool) -> Self {
match (is_mutable, is_ref) {
(true, true) => BindingAnnotation::RefMut,
(false, true) => BindingAnnotation::Ref,
(true, false) => BindingAnnotation::Mutable,
(false, false) => BindingAnnotation::Unannotated,
}
}
}
#[derive(Debug, Clone, Eq, PartialEq)]
pub struct RecordFieldPat {
pub(crate) name: Name,
pub(crate) pat: PatId,
}
/// Close relative to rustc's hir::PatKind
#[derive(Debug, Clone, Eq, PartialEq)]
pub enum Pat {
Missing,
Wild,
Tuple(Vec<PatId>),
Record {
path: Option<Path>,
args: Vec<RecordFieldPat>,
// FIXME: 'ellipsis' option
},
Range {
start: ExprId,
end: ExprId,
},
Slice {
prefix: Vec<PatId>,
rest: Option<PatId>,
suffix: Vec<PatId>,
},
Path(Path),
Lit(ExprId),
Bind {
mode: BindingAnnotation,
name: Name,
subpat: Option<PatId>,
},
TupleStruct {
path: Option<Path>,
args: Vec<PatId>,
},
Ref {
pat: PatId,
mutability: Mutability,
},
}
impl Pat {
pub fn walk_child_pats(&self, mut f: impl FnMut(PatId)) {
match self {
Pat::Range { .. } | Pat::Lit(..) | Pat::Path(..) | Pat::Wild | Pat::Missing => {}
Pat::Bind { subpat, .. } => {
subpat.iter().copied().for_each(f);
}
Pat::Tuple(args) | Pat::TupleStruct { args, .. } => {
args.iter().copied().for_each(f);
}
Pat::Ref { pat, .. } => f(*pat),
Pat::Slice { prefix, rest, suffix } => {
let total_iter = prefix.iter().chain(rest.iter()).chain(suffix.iter());
total_iter.copied().for_each(f);
}
Pat::Record { args, .. } => {
args.iter().map(|f| f.pat).for_each(f);
}
}
}
}
// Queries
pub(crate) fn body_with_source_map_query(
db: &impl HirDatabase,
def: DefWithBody,
) -> (Arc<Body>, Arc<BodySourceMap>) {
let mut params = None;
let (file_id, body) = match def {
DefWithBody::Function(f) => {
let src = f.source(db);
params = src.ast.param_list();
(src.file_id, src.ast.body().map(ast::Expr::from))
}
DefWithBody::Const(c) => {
let src = c.source(db);
(src.file_id, src.ast.body())
}
DefWithBody::Static(s) => {
let src = s.source(db);
(src.file_id, src.ast.body())
}
};
let (body, source_map) = lower::lower(db, def.resolver(db), file_id, def, params, body);
(Arc::new(body), Arc::new(source_map))
}
pub(crate) fn body_hir_query(db: &impl HirDatabase, def: DefWithBody) -> Arc<Body> {
db.body_with_source_map(def).0
}
|
