diff options
author | Benjamin Coenen <[email protected]> | 2020-04-07 16:59:09 +0100 |
---|---|---|
committer | Benjamin Coenen <[email protected]> | 2020-04-07 16:59:09 +0100 |
commit | 18a5e164838e1dc2abcc6b79d4fc2f96ffd2507c (patch) | |
tree | bc80b5c49c3b7ba31c7fe967bb34fe14bac9d5ed /crates/ra_hir_ty | |
parent | ab864ed259c10ff51f7c9c3421d098eeea7b0245 (diff) | |
parent | 33c364b545350134b945fbca834194fd1a28fe08 (diff) |
Merge branch 'master' of github.com:rust-analyzer/rust-analyzer
Diffstat (limited to 'crates/ra_hir_ty')
-rw-r--r-- | crates/ra_hir_ty/Cargo.toml | 1 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/_match.rs | 1411 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/diagnostics.rs | 21 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/expr.rs | 89 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/infer/pat.rs | 6 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/infer/path.rs | 12 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/lib.rs | 9 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/test_db.rs | 6 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/tests.rs | 3 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/tests/traits.rs | 25 | ||||
-rw-r--r-- | crates/ra_hir_ty/src/traits/chalk.rs | 7 |
11 files changed, 1579 insertions, 11 deletions
diff --git a/crates/ra_hir_ty/Cargo.toml b/crates/ra_hir_ty/Cargo.toml index 45be08430..9a4a7aa6f 100644 --- a/crates/ra_hir_ty/Cargo.toml +++ b/crates/ra_hir_ty/Cargo.toml | |||
@@ -9,6 +9,7 @@ doctest = false | |||
9 | 9 | ||
10 | [dependencies] | 10 | [dependencies] |
11 | arrayvec = "0.5.1" | 11 | arrayvec = "0.5.1" |
12 | smallvec = "1.2.0" | ||
12 | ena = "0.13.1" | 13 | ena = "0.13.1" |
13 | log = "0.4.8" | 14 | log = "0.4.8" |
14 | rustc-hash = "1.1.0" | 15 | rustc-hash = "1.1.0" |
diff --git a/crates/ra_hir_ty/src/_match.rs b/crates/ra_hir_ty/src/_match.rs new file mode 100644 index 000000000..f29a25505 --- /dev/null +++ b/crates/ra_hir_ty/src/_match.rs | |||
@@ -0,0 +1,1411 @@ | |||
1 | //! This module implements match statement exhaustiveness checking and usefulness checking | ||
2 | //! for match arms. | ||
3 | //! | ||
4 | //! It is modeled on the rustc module `librustc_mir_build::hair::pattern::_match`, which | ||
5 | //! contains very detailed documentation about the algorithms used here. I've duplicated | ||
6 | //! most of that documentation below. | ||
7 | //! | ||
8 | //! This file includes the logic for exhaustiveness and usefulness checking for | ||
9 | //! pattern-matching. Specifically, given a list of patterns for a type, we can | ||
10 | //! tell whether: | ||
11 | //! (a) the patterns cover every possible constructor for the type [exhaustiveness] | ||
12 | //! (b) each pattern is necessary [usefulness] | ||
13 | //! | ||
14 | //! The algorithm implemented here is a modified version of the one described in: | ||
15 | //! http://moscova.inria.fr/~maranget/papers/warn/index.html | ||
16 | //! However, to save future implementors from reading the original paper, we | ||
17 | //! summarise the algorithm here to hopefully save time and be a little clearer | ||
18 | //! (without being so rigorous). | ||
19 | //! | ||
20 | //! The core of the algorithm revolves about a "usefulness" check. In particular, we | ||
21 | //! are trying to compute a predicate `U(P, p)` where `P` is a list of patterns (we refer to this as | ||
22 | //! a matrix). `U(P, p)` represents whether, given an existing list of patterns | ||
23 | //! `P_1 ..= P_m`, adding a new pattern `p` will be "useful" (that is, cover previously- | ||
24 | //! uncovered values of the type). | ||
25 | //! | ||
26 | //! If we have this predicate, then we can easily compute both exhaustiveness of an | ||
27 | //! entire set of patterns and the individual usefulness of each one. | ||
28 | //! (a) the set of patterns is exhaustive iff `U(P, _)` is false (i.e., adding a wildcard | ||
29 | //! match doesn't increase the number of values we're matching) | ||
30 | //! (b) a pattern `P_i` is not useful if `U(P[0..=(i-1), P_i)` is false (i.e., adding a | ||
31 | //! pattern to those that have come before it doesn't increase the number of values | ||
32 | //! we're matching). | ||
33 | //! | ||
34 | //! During the course of the algorithm, the rows of the matrix won't just be individual patterns, | ||
35 | //! but rather partially-deconstructed patterns in the form of a list of patterns. The paper | ||
36 | //! calls those pattern-vectors, and we will call them pattern-stacks. The same holds for the | ||
37 | //! new pattern `p`. | ||
38 | //! | ||
39 | //! For example, say we have the following: | ||
40 | //! ``` | ||
41 | //! // x: (Option<bool>, Result<()>) | ||
42 | //! match x { | ||
43 | //! (Some(true), _) => {} | ||
44 | //! (None, Err(())) => {} | ||
45 | //! (None, Err(_)) => {} | ||
46 | //! } | ||
47 | //! ``` | ||
48 | //! Here, the matrix `P` starts as: | ||
49 | //! [ | ||
50 | //! [(Some(true), _)], | ||
51 | //! [(None, Err(()))], | ||
52 | //! [(None, Err(_))], | ||
53 | //! ] | ||
54 | //! We can tell it's not exhaustive, because `U(P, _)` is true (we're not covering | ||
55 | //! `[(Some(false), _)]`, for instance). In addition, row 3 is not useful, because | ||
56 | //! all the values it covers are already covered by row 2. | ||
57 | //! | ||
58 | //! A list of patterns can be thought of as a stack, because we are mainly interested in the top of | ||
59 | //! the stack at any given point, and we can pop or apply constructors to get new pattern-stacks. | ||
60 | //! To match the paper, the top of the stack is at the beginning / on the left. | ||
61 | //! | ||
62 | //! There are two important operations on pattern-stacks necessary to understand the algorithm: | ||
63 | //! 1. We can pop a given constructor off the top of a stack. This operation is called | ||
64 | //! `specialize`, and is denoted `S(c, p)` where `c` is a constructor (like `Some` or | ||
65 | //! `None`) and `p` a pattern-stack. | ||
66 | //! If the pattern on top of the stack can cover `c`, this removes the constructor and | ||
67 | //! pushes its arguments onto the stack. It also expands OR-patterns into distinct patterns. | ||
68 | //! Otherwise the pattern-stack is discarded. | ||
69 | //! This essentially filters those pattern-stacks whose top covers the constructor `c` and | ||
70 | //! discards the others. | ||
71 | //! | ||
72 | //! For example, the first pattern above initially gives a stack `[(Some(true), _)]`. If we | ||
73 | //! pop the tuple constructor, we are left with `[Some(true), _]`, and if we then pop the | ||
74 | //! `Some` constructor we get `[true, _]`. If we had popped `None` instead, we would get | ||
75 | //! nothing back. | ||
76 | //! | ||
77 | //! This returns zero or more new pattern-stacks, as follows. We look at the pattern `p_1` | ||
78 | //! on top of the stack, and we have four cases: | ||
79 | //! 1.1. `p_1 = c(r_1, .., r_a)`, i.e. the top of the stack has constructor `c`. We | ||
80 | //! push onto the stack the arguments of this constructor, and return the result: | ||
81 | //! r_1, .., r_a, p_2, .., p_n | ||
82 | //! 1.2. `p_1 = c'(r_1, .., r_a')` where `c ≠ c'`. We discard the current stack and | ||
83 | //! return nothing. | ||
84 | //! 1.3. `p_1 = _`. We push onto the stack as many wildcards as the constructor `c` has | ||
85 | //! arguments (its arity), and return the resulting stack: | ||
86 | //! _, .., _, p_2, .., p_n | ||
87 | //! 1.4. `p_1 = r_1 | r_2`. We expand the OR-pattern and then recurse on each resulting | ||
88 | //! stack: | ||
89 | //! S(c, (r_1, p_2, .., p_n)) | ||
90 | //! S(c, (r_2, p_2, .., p_n)) | ||
91 | //! | ||
92 | //! 2. We can pop a wildcard off the top of the stack. This is called `D(p)`, where `p` is | ||
93 | //! a pattern-stack. | ||
94 | //! This is used when we know there are missing constructor cases, but there might be | ||
95 | //! existing wildcard patterns, so to check the usefulness of the matrix, we have to check | ||
96 | //! all its *other* components. | ||
97 | //! | ||
98 | //! It is computed as follows. We look at the pattern `p_1` on top of the stack, | ||
99 | //! and we have three cases: | ||
100 | //! 1.1. `p_1 = c(r_1, .., r_a)`. We discard the current stack and return nothing. | ||
101 | //! 1.2. `p_1 = _`. We return the rest of the stack: | ||
102 | //! p_2, .., p_n | ||
103 | //! 1.3. `p_1 = r_1 | r_2`. We expand the OR-pattern and then recurse on each resulting | ||
104 | //! stack. | ||
105 | //! D((r_1, p_2, .., p_n)) | ||
106 | //! D((r_2, p_2, .., p_n)) | ||
107 | //! | ||
108 | //! Note that the OR-patterns are not always used directly in Rust, but are used to derive the | ||
109 | //! exhaustive integer matching rules, so they're written here for posterity. | ||
110 | //! | ||
111 | //! Both those operations extend straightforwardly to a list or pattern-stacks, i.e. a matrix, by | ||
112 | //! working row-by-row. Popping a constructor ends up keeping only the matrix rows that start with | ||
113 | //! the given constructor, and popping a wildcard keeps those rows that start with a wildcard. | ||
114 | //! | ||
115 | //! | ||
116 | //! The algorithm for computing `U` | ||
117 | //! ------------------------------- | ||
118 | //! The algorithm is inductive (on the number of columns: i.e., components of tuple patterns). | ||
119 | //! That means we're going to check the components from left-to-right, so the algorithm | ||
120 | //! operates principally on the first component of the matrix and new pattern-stack `p`. | ||
121 | //! This algorithm is realised in the `is_useful` function. | ||
122 | //! | ||
123 | //! Base case. (`n = 0`, i.e., an empty tuple pattern) | ||
124 | //! - If `P` already contains an empty pattern (i.e., if the number of patterns `m > 0`), | ||
125 | //! then `U(P, p)` is false. | ||
126 | //! - Otherwise, `P` must be empty, so `U(P, p)` is true. | ||
127 | //! | ||
128 | //! Inductive step. (`n > 0`, i.e., whether there's at least one column | ||
129 | //! [which may then be expanded into further columns later]) | ||
130 | //! We're going to match on the top of the new pattern-stack, `p_1`. | ||
131 | //! - If `p_1 == c(r_1, .., r_a)`, i.e. we have a constructor pattern. | ||
132 | //! Then, the usefulness of `p_1` can be reduced to whether it is useful when | ||
133 | //! we ignore all the patterns in the first column of `P` that involve other constructors. | ||
134 | //! This is where `S(c, P)` comes in: | ||
135 | //! `U(P, p) := U(S(c, P), S(c, p))` | ||
136 | //! This special case is handled in `is_useful_specialized`. | ||
137 | //! | ||
138 | //! For example, if `P` is: | ||
139 | //! [ | ||
140 | //! [Some(true), _], | ||
141 | //! [None, 0], | ||
142 | //! ] | ||
143 | //! and `p` is [Some(false), 0], then we don't care about row 2 since we know `p` only | ||
144 | //! matches values that row 2 doesn't. For row 1 however, we need to dig into the | ||
145 | //! arguments of `Some` to know whether some new value is covered. So we compute | ||
146 | //! `U([[true, _]], [false, 0])`. | ||
147 | //! | ||
148 | //! - If `p_1 == _`, then we look at the list of constructors that appear in the first | ||
149 | //! component of the rows of `P`: | ||
150 | //! + If there are some constructors that aren't present, then we might think that the | ||
151 | //! wildcard `_` is useful, since it covers those constructors that weren't covered | ||
152 | //! before. | ||
153 | //! That's almost correct, but only works if there were no wildcards in those first | ||
154 | //! components. So we need to check that `p` is useful with respect to the rows that | ||
155 | //! start with a wildcard, if there are any. This is where `D` comes in: | ||
156 | //! `U(P, p) := U(D(P), D(p))` | ||
157 | //! | ||
158 | //! For example, if `P` is: | ||
159 | //! [ | ||
160 | //! [_, true, _], | ||
161 | //! [None, false, 1], | ||
162 | //! ] | ||
163 | //! and `p` is [_, false, _], the `Some` constructor doesn't appear in `P`. So if we | ||
164 | //! only had row 2, we'd know that `p` is useful. However row 1 starts with a | ||
165 | //! wildcard, so we need to check whether `U([[true, _]], [false, 1])`. | ||
166 | //! | ||
167 | //! + Otherwise, all possible constructors (for the relevant type) are present. In this | ||
168 | //! case we must check whether the wildcard pattern covers any unmatched value. For | ||
169 | //! that, we can think of the `_` pattern as a big OR-pattern that covers all | ||
170 | //! possible constructors. For `Option`, that would mean `_ = None | Some(_)` for | ||
171 | //! example. The wildcard pattern is useful in this case if it is useful when | ||
172 | //! specialized to one of the possible constructors. So we compute: | ||
173 | //! `U(P, p) := ∃(k ϵ constructors) U(S(k, P), S(k, p))` | ||
174 | //! | ||
175 | //! For example, if `P` is: | ||
176 | //! [ | ||
177 | //! [Some(true), _], | ||
178 | //! [None, false], | ||
179 | //! ] | ||
180 | //! and `p` is [_, false], both `None` and `Some` constructors appear in the first | ||
181 | //! components of `P`. We will therefore try popping both constructors in turn: we | ||
182 | //! compute U([[true, _]], [_, false]) for the `Some` constructor, and U([[false]], | ||
183 | //! [false]) for the `None` constructor. The first case returns true, so we know that | ||
184 | //! `p` is useful for `P`. Indeed, it matches `[Some(false), _]` that wasn't matched | ||
185 | //! before. | ||
186 | //! | ||
187 | //! - If `p_1 == r_1 | r_2`, then the usefulness depends on each `r_i` separately: | ||
188 | //! `U(P, p) := U(P, (r_1, p_2, .., p_n)) | ||
189 | //! || U(P, (r_2, p_2, .., p_n))` | ||
190 | use std::sync::Arc; | ||
191 | |||
192 | use smallvec::{smallvec, SmallVec}; | ||
193 | |||
194 | use crate::{ | ||
195 | db::HirDatabase, | ||
196 | expr::{Body, Expr, Literal, Pat, PatId}, | ||
197 | InferenceResult, | ||
198 | }; | ||
199 | use hir_def::{adt::VariantData, EnumVariantId, VariantId}; | ||
200 | |||
201 | #[derive(Debug, Clone, Copy)] | ||
202 | /// Either a pattern from the source code being analyzed, represented as | ||
203 | /// as `PatId`, or a `Wild` pattern which is created as an intermediate | ||
204 | /// step in the match checking algorithm and thus is not backed by a | ||
205 | /// real `PatId`. | ||
206 | /// | ||
207 | /// Note that it is totally valid for the `PatId` variant to contain | ||
208 | /// a `PatId` which resolves to a `Wild` pattern, if that wild pattern | ||
209 | /// exists in the source code being analyzed. | ||
210 | enum PatIdOrWild { | ||
211 | PatId(PatId), | ||
212 | Wild, | ||
213 | } | ||
214 | |||
215 | impl PatIdOrWild { | ||
216 | fn as_pat(self, cx: &MatchCheckCtx) -> Pat { | ||
217 | match self { | ||
218 | PatIdOrWild::PatId(id) => cx.body.pats[id].clone(), | ||
219 | PatIdOrWild::Wild => Pat::Wild, | ||
220 | } | ||
221 | } | ||
222 | |||
223 | fn as_id(self) -> Option<PatId> { | ||
224 | match self { | ||
225 | PatIdOrWild::PatId(id) => Some(id), | ||
226 | PatIdOrWild::Wild => None, | ||
227 | } | ||
228 | } | ||
229 | } | ||
230 | |||
231 | impl From<PatId> for PatIdOrWild { | ||
232 | fn from(pat_id: PatId) -> Self { | ||
233 | Self::PatId(pat_id) | ||
234 | } | ||
235 | } | ||
236 | |||
237 | #[derive(Debug, Clone, Copy, PartialEq)] | ||
238 | pub struct MatchCheckNotImplemented; | ||
239 | |||
240 | /// The return type of `is_useful` is either an indication of usefulness | ||
241 | /// of the match arm, or an error in the case the match statement | ||
242 | /// is made up of types for which exhaustiveness checking is currently | ||
243 | /// not completely implemented. | ||
244 | /// | ||
245 | /// The `std::result::Result` type is used here rather than a custom enum | ||
246 | /// to allow the use of `?`. | ||
247 | pub type MatchCheckResult<T> = Result<T, MatchCheckNotImplemented>; | ||
248 | |||
249 | #[derive(Debug)] | ||
250 | /// A row in a Matrix. | ||
251 | /// | ||
252 | /// This type is modeled from the struct of the same name in `rustc`. | ||
253 | pub(crate) struct PatStack(PatStackInner); | ||
254 | type PatStackInner = SmallVec<[PatIdOrWild; 2]>; | ||
255 | |||
256 | impl PatStack { | ||
257 | pub(crate) fn from_pattern(pat_id: PatId) -> PatStack { | ||
258 | Self(smallvec!(pat_id.into())) | ||
259 | } | ||
260 | |||
261 | pub(crate) fn from_wild() -> PatStack { | ||
262 | Self(smallvec!(PatIdOrWild::Wild)) | ||
263 | } | ||
264 | |||
265 | fn from_slice(slice: &[PatIdOrWild]) -> PatStack { | ||
266 | Self(SmallVec::from_slice(slice)) | ||
267 | } | ||
268 | |||
269 | fn from_vec(v: PatStackInner) -> PatStack { | ||
270 | Self(v) | ||
271 | } | ||
272 | |||
273 | fn is_empty(&self) -> bool { | ||
274 | self.0.is_empty() | ||
275 | } | ||
276 | |||
277 | fn head(&self) -> PatIdOrWild { | ||
278 | self.0[0] | ||
279 | } | ||
280 | |||
281 | fn get_head(&self) -> Option<PatIdOrWild> { | ||
282 | self.0.first().copied() | ||
283 | } | ||
284 | |||
285 | fn to_tail(&self) -> PatStack { | ||
286 | Self::from_slice(&self.0[1..]) | ||
287 | } | ||
288 | |||
289 | fn replace_head_with(&self, pat_ids: &[PatId]) -> PatStack { | ||
290 | let mut patterns: PatStackInner = smallvec![]; | ||
291 | for pat in pat_ids { | ||
292 | patterns.push((*pat).into()); | ||
293 | } | ||
294 | for pat in &self.0[1..] { | ||
295 | patterns.push(*pat); | ||
296 | } | ||
297 | PatStack::from_vec(patterns) | ||
298 | } | ||
299 | |||
300 | /// Computes `D(self)`. | ||
301 | /// | ||
302 | /// See the module docs and the associated documentation in rustc for details. | ||
303 | fn specialize_wildcard(&self, cx: &MatchCheckCtx) -> Option<PatStack> { | ||
304 | if matches!(self.head().as_pat(cx), Pat::Wild) { | ||
305 | Some(self.to_tail()) | ||
306 | } else { | ||
307 | None | ||
308 | } | ||
309 | } | ||
310 | |||
311 | /// Computes `S(constructor, self)`. | ||
312 | /// | ||
313 | /// See the module docs and the associated documentation in rustc for details. | ||
314 | fn specialize_constructor( | ||
315 | &self, | ||
316 | cx: &MatchCheckCtx, | ||
317 | constructor: &Constructor, | ||
318 | ) -> MatchCheckResult<Option<PatStack>> { | ||
319 | let result = match (self.head().as_pat(cx), constructor) { | ||
320 | (Pat::Tuple(ref pat_ids), Constructor::Tuple { arity }) => { | ||
321 | debug_assert_eq!( | ||
322 | pat_ids.len(), | ||
323 | *arity, | ||
324 | "we type check before calling this code, so we should never hit this case", | ||
325 | ); | ||
326 | |||
327 | Some(self.replace_head_with(pat_ids)) | ||
328 | } | ||
329 | (Pat::Lit(lit_expr), Constructor::Bool(constructor_val)) => { | ||
330 | match cx.body.exprs[lit_expr] { | ||
331 | Expr::Literal(Literal::Bool(pat_val)) if *constructor_val == pat_val => { | ||
332 | Some(self.to_tail()) | ||
333 | } | ||
334 | // it was a bool but the value doesn't match | ||
335 | Expr::Literal(Literal::Bool(_)) => None, | ||
336 | // perhaps this is actually unreachable given we have | ||
337 | // already checked that these match arms have the appropriate type? | ||
338 | _ => return Err(MatchCheckNotImplemented), | ||
339 | } | ||
340 | } | ||
341 | (Pat::Wild, constructor) => Some(self.expand_wildcard(cx, constructor)?), | ||
342 | (Pat::Path(_), Constructor::Enum(constructor)) => { | ||
343 | // enums with no associated data become `Pat::Path` | ||
344 | let pat_id = self.head().as_id().expect("we know this isn't a wild"); | ||
345 | if !enum_variant_matches(cx, pat_id, *constructor) { | ||
346 | None | ||
347 | } else { | ||
348 | Some(self.to_tail()) | ||
349 | } | ||
350 | } | ||
351 | (Pat::TupleStruct { args: ref pat_ids, .. }, Constructor::Enum(constructor)) => { | ||
352 | let pat_id = self.head().as_id().expect("we know this isn't a wild"); | ||
353 | if !enum_variant_matches(cx, pat_id, *constructor) { | ||
354 | None | ||
355 | } else { | ||
356 | Some(self.replace_head_with(pat_ids)) | ||
357 | } | ||
358 | } | ||
359 | (Pat::Or(_), _) => return Err(MatchCheckNotImplemented), | ||
360 | (_, _) => return Err(MatchCheckNotImplemented), | ||
361 | }; | ||
362 | |||
363 | Ok(result) | ||
364 | } | ||
365 | |||
366 | /// A special case of `specialize_constructor` where the head of the pattern stack | ||
367 | /// is a Wild pattern. | ||
368 | /// | ||
369 | /// Replaces the Wild pattern at the head of the pattern stack with N Wild patterns | ||
370 | /// (N >= 0), where N is the arity of the given constructor. | ||
371 | fn expand_wildcard( | ||
372 | &self, | ||
373 | cx: &MatchCheckCtx, | ||
374 | constructor: &Constructor, | ||
375 | ) -> MatchCheckResult<PatStack> { | ||
376 | assert_eq!( | ||
377 | Pat::Wild, | ||
378 | self.head().as_pat(cx), | ||
379 | "expand_wildcard must only be called on PatStack with wild at head", | ||
380 | ); | ||
381 | |||
382 | let mut patterns: PatStackInner = smallvec![]; | ||
383 | |||
384 | for _ in 0..constructor.arity(cx)? { | ||
385 | patterns.push(PatIdOrWild::Wild); | ||
386 | } | ||
387 | |||
388 | for pat in &self.0[1..] { | ||
389 | patterns.push(*pat); | ||
390 | } | ||
391 | |||
392 | Ok(PatStack::from_vec(patterns)) | ||
393 | } | ||
394 | } | ||
395 | |||
396 | #[derive(Debug)] | ||
397 | /// A collection of PatStack. | ||
398 | /// | ||
399 | /// This type is modeled from the struct of the same name in `rustc`. | ||
400 | pub(crate) struct Matrix(Vec<PatStack>); | ||
401 | |||
402 | impl Matrix { | ||
403 | pub(crate) fn empty() -> Self { | ||
404 | Self(vec![]) | ||
405 | } | ||
406 | |||
407 | pub(crate) fn push(&mut self, cx: &MatchCheckCtx, row: PatStack) { | ||
408 | if let Some(Pat::Or(pat_ids)) = row.get_head().map(|pat_id| pat_id.as_pat(cx)) { | ||
409 | // Or patterns are expanded here | ||
410 | for pat_id in pat_ids { | ||
411 | self.0.push(PatStack::from_pattern(pat_id)); | ||
412 | } | ||
413 | } else { | ||
414 | self.0.push(row); | ||
415 | } | ||
416 | } | ||
417 | |||
418 | fn is_empty(&self) -> bool { | ||
419 | self.0.is_empty() | ||
420 | } | ||
421 | |||
422 | fn heads(&self) -> Vec<PatIdOrWild> { | ||
423 | self.0.iter().map(|p| p.head()).collect() | ||
424 | } | ||
425 | |||
426 | /// Computes `D(self)` for each contained PatStack. | ||
427 | /// | ||
428 | /// See the module docs and the associated documentation in rustc for details. | ||
429 | fn specialize_wildcard(&self, cx: &MatchCheckCtx) -> Self { | ||
430 | Self::collect(cx, self.0.iter().filter_map(|r| r.specialize_wildcard(cx))) | ||
431 | } | ||
432 | |||
433 | /// Computes `S(constructor, self)` for each contained PatStack. | ||
434 | /// | ||
435 | /// See the module docs and the associated documentation in rustc for details. | ||
436 | fn specialize_constructor( | ||
437 | &self, | ||
438 | cx: &MatchCheckCtx, | ||
439 | constructor: &Constructor, | ||
440 | ) -> MatchCheckResult<Self> { | ||
441 | let mut new_matrix = Matrix::empty(); | ||
442 | for pat in &self.0 { | ||
443 | if let Some(pat) = pat.specialize_constructor(cx, constructor)? { | ||
444 | new_matrix.push(cx, pat); | ||
445 | } | ||
446 | } | ||
447 | |||
448 | Ok(new_matrix) | ||
449 | } | ||
450 | |||
451 | fn collect<T: IntoIterator<Item = PatStack>>(cx: &MatchCheckCtx, iter: T) -> Self { | ||
452 | let mut matrix = Matrix::empty(); | ||
453 | |||
454 | for pat in iter { | ||
455 | // using push ensures we expand or-patterns | ||
456 | matrix.push(cx, pat); | ||
457 | } | ||
458 | |||
459 | matrix | ||
460 | } | ||
461 | } | ||
462 | |||
463 | #[derive(Clone, Debug, PartialEq)] | ||
464 | /// An indication of the usefulness of a given match arm, where | ||
465 | /// usefulness is defined as matching some patterns which were | ||
466 | /// not matched by an prior match arms. | ||
467 | /// | ||
468 | /// We may eventually need an `Unknown` variant here. | ||
469 | pub enum Usefulness { | ||
470 | Useful, | ||
471 | NotUseful, | ||
472 | } | ||
473 | |||
474 | pub struct MatchCheckCtx<'a> { | ||
475 | pub body: Arc<Body>, | ||
476 | pub infer: Arc<InferenceResult>, | ||
477 | pub db: &'a dyn HirDatabase, | ||
478 | } | ||
479 | |||
480 | /// Given a set of patterns `matrix`, and pattern to consider `v`, determines | ||
481 | /// whether `v` is useful. A pattern is useful if it covers cases which were | ||
482 | /// not previously covered. | ||
483 | /// | ||
484 | /// When calling this function externally (that is, not the recursive calls) it | ||
485 | /// expected that you have already type checked the match arms. All patterns in | ||
486 | /// matrix should be the same type as v, as well as they should all be the same | ||
487 | /// type as the match expression. | ||
488 | pub(crate) fn is_useful( | ||
489 | cx: &MatchCheckCtx, | ||
490 | matrix: &Matrix, | ||
491 | v: &PatStack, | ||
492 | ) -> MatchCheckResult<Usefulness> { | ||
493 | if v.is_empty() { | ||
494 | let result = if matrix.is_empty() { Usefulness::Useful } else { Usefulness::NotUseful }; | ||
495 | |||
496 | return Ok(result); | ||
497 | } | ||
498 | |||
499 | if let Pat::Or(pat_ids) = v.head().as_pat(cx) { | ||
500 | let mut found_unimplemented = false; | ||
501 | let any_useful = pat_ids.iter().any(|&pat_id| { | ||
502 | let v = PatStack::from_pattern(pat_id); | ||
503 | |||
504 | match is_useful(cx, matrix, &v) { | ||
505 | Ok(Usefulness::Useful) => true, | ||
506 | Ok(Usefulness::NotUseful) => false, | ||
507 | _ => { | ||
508 | found_unimplemented = true; | ||
509 | false | ||
510 | } | ||
511 | } | ||
512 | }); | ||
513 | |||
514 | return if any_useful { | ||
515 | Ok(Usefulness::Useful) | ||
516 | } else if found_unimplemented { | ||
517 | Err(MatchCheckNotImplemented) | ||
518 | } else { | ||
519 | Ok(Usefulness::NotUseful) | ||
520 | }; | ||
521 | } | ||
522 | |||
523 | if let Some(constructor) = pat_constructor(cx, v.head())? { | ||
524 | let matrix = matrix.specialize_constructor(&cx, &constructor)?; | ||
525 | let v = v | ||
526 | .specialize_constructor(&cx, &constructor)? | ||
527 | .expect("we know this can't fail because we get the constructor from `v.head()` above"); | ||
528 | |||
529 | is_useful(&cx, &matrix, &v) | ||
530 | } else { | ||
531 | // expanding wildcard | ||
532 | let mut used_constructors: Vec<Constructor> = vec![]; | ||
533 | for pat in matrix.heads() { | ||
534 | if let Some(constructor) = pat_constructor(cx, pat)? { | ||
535 | used_constructors.push(constructor); | ||
536 | } | ||
537 | } | ||
538 | |||
539 | // We assume here that the first constructor is the "correct" type. Since we | ||
540 | // only care about the "type" of the constructor (i.e. if it is a bool we | ||
541 | // don't care about the value), this assumption should be valid as long as | ||
542 | // the match statement is well formed. We currently uphold this invariant by | ||
543 | // filtering match arms before calling `is_useful`, only passing in match arms | ||
544 | // whose type matches the type of the match expression. | ||
545 | match &used_constructors.first() { | ||
546 | Some(constructor) if all_constructors_covered(&cx, constructor, &used_constructors) => { | ||
547 | // If all constructors are covered, then we need to consider whether | ||
548 | // any values are covered by this wildcard. | ||
549 | // | ||
550 | // For example, with matrix '[[Some(true)], [None]]', all | ||
551 | // constructors are covered (`Some`/`None`), so we need | ||
552 | // to perform specialization to see that our wildcard will cover | ||
553 | // the `Some(false)` case. | ||
554 | // | ||
555 | // Here we create a constructor for each variant and then check | ||
556 | // usefulness after specializing for that constructor. | ||
557 | let mut found_unimplemented = false; | ||
558 | for constructor in constructor.all_constructors(cx) { | ||
559 | let matrix = matrix.specialize_constructor(&cx, &constructor)?; | ||
560 | let v = v.expand_wildcard(&cx, &constructor)?; | ||
561 | |||
562 | match is_useful(&cx, &matrix, &v) { | ||
563 | Ok(Usefulness::Useful) => return Ok(Usefulness::Useful), | ||
564 | Ok(Usefulness::NotUseful) => continue, | ||
565 | _ => found_unimplemented = true, | ||
566 | }; | ||
567 | } | ||
568 | |||
569 | if found_unimplemented { | ||
570 | Err(MatchCheckNotImplemented) | ||
571 | } else { | ||
572 | Ok(Usefulness::NotUseful) | ||
573 | } | ||
574 | } | ||
575 | _ => { | ||
576 | // Either not all constructors are covered, or the only other arms | ||
577 | // are wildcards. Either way, this pattern is useful if it is useful | ||
578 | // when compared to those arms with wildcards. | ||
579 | let matrix = matrix.specialize_wildcard(&cx); | ||
580 | let v = v.to_tail(); | ||
581 | |||
582 | is_useful(&cx, &matrix, &v) | ||
583 | } | ||
584 | } | ||
585 | } | ||
586 | } | ||
587 | |||
588 | #[derive(Debug, Clone, Copy)] | ||
589 | /// Similar to TypeCtor, but includes additional information about the specific | ||
590 | /// value being instantiated. For example, TypeCtor::Bool doesn't contain the | ||
591 | /// boolean value. | ||
592 | enum Constructor { | ||
593 | Bool(bool), | ||
594 | Tuple { arity: usize }, | ||
595 | Enum(EnumVariantId), | ||
596 | } | ||
597 | |||
598 | impl Constructor { | ||
599 | fn arity(&self, cx: &MatchCheckCtx) -> MatchCheckResult<usize> { | ||
600 | let arity = match self { | ||
601 | Constructor::Bool(_) => 0, | ||
602 | Constructor::Tuple { arity } => *arity, | ||
603 | Constructor::Enum(e) => { | ||
604 | match cx.db.enum_data(e.parent).variants[e.local_id].variant_data.as_ref() { | ||
605 | VariantData::Tuple(struct_field_data) => struct_field_data.len(), | ||
606 | VariantData::Unit => 0, | ||
607 | _ => return Err(MatchCheckNotImplemented), | ||
608 | } | ||
609 | } | ||
610 | }; | ||
611 | |||
612 | Ok(arity) | ||
613 | } | ||
614 | |||
615 | fn all_constructors(&self, cx: &MatchCheckCtx) -> Vec<Constructor> { | ||
616 | match self { | ||
617 | Constructor::Bool(_) => vec![Constructor::Bool(true), Constructor::Bool(false)], | ||
618 | Constructor::Tuple { .. } => vec![*self], | ||
619 | Constructor::Enum(e) => cx | ||
620 | .db | ||
621 | .enum_data(e.parent) | ||
622 | .variants | ||
623 | .iter() | ||
624 | .map(|(local_id, _)| { | ||
625 | Constructor::Enum(EnumVariantId { parent: e.parent, local_id }) | ||
626 | }) | ||
627 | .collect(), | ||
628 | } | ||
629 | } | ||
630 | } | ||
631 | |||
632 | /// Returns the constructor for the given pattern. Should only return None | ||
633 | /// in the case of a Wild pattern. | ||
634 | fn pat_constructor(cx: &MatchCheckCtx, pat: PatIdOrWild) -> MatchCheckResult<Option<Constructor>> { | ||
635 | let res = match pat.as_pat(cx) { | ||
636 | Pat::Wild => None, | ||
637 | Pat::Tuple(pats) => Some(Constructor::Tuple { arity: pats.len() }), | ||
638 | Pat::Lit(lit_expr) => match cx.body.exprs[lit_expr] { | ||
639 | Expr::Literal(Literal::Bool(val)) => Some(Constructor::Bool(val)), | ||
640 | _ => return Err(MatchCheckNotImplemented), | ||
641 | }, | ||
642 | Pat::TupleStruct { .. } | Pat::Path(_) => { | ||
643 | let pat_id = pat.as_id().expect("we already know this pattern is not a wild"); | ||
644 | let variant_id = | ||
645 | cx.infer.variant_resolution_for_pat(pat_id).ok_or(MatchCheckNotImplemented)?; | ||
646 | match variant_id { | ||
647 | VariantId::EnumVariantId(enum_variant_id) => { | ||
648 | Some(Constructor::Enum(enum_variant_id)) | ||
649 | } | ||
650 | _ => return Err(MatchCheckNotImplemented), | ||
651 | } | ||
652 | } | ||
653 | _ => return Err(MatchCheckNotImplemented), | ||
654 | }; | ||
655 | |||
656 | Ok(res) | ||
657 | } | ||
658 | |||
659 | fn all_constructors_covered( | ||
660 | cx: &MatchCheckCtx, | ||
661 | constructor: &Constructor, | ||
662 | used_constructors: &[Constructor], | ||
663 | ) -> bool { | ||
664 | match constructor { | ||
665 | Constructor::Tuple { arity } => { | ||
666 | used_constructors.iter().any(|constructor| match constructor { | ||
667 | Constructor::Tuple { arity: used_arity } => arity == used_arity, | ||
668 | _ => false, | ||
669 | }) | ||
670 | } | ||
671 | Constructor::Bool(_) => { | ||
672 | if used_constructors.is_empty() { | ||
673 | return false; | ||
674 | } | ||
675 | |||
676 | let covers_true = | ||
677 | used_constructors.iter().any(|c| matches!(c, Constructor::Bool(true))); | ||
678 | let covers_false = | ||
679 | used_constructors.iter().any(|c| matches!(c, Constructor::Bool(false))); | ||
680 | |||
681 | covers_true && covers_false | ||
682 | } | ||
683 | Constructor::Enum(e) => cx.db.enum_data(e.parent).variants.iter().all(|(id, _)| { | ||
684 | for constructor in used_constructors { | ||
685 | if let Constructor::Enum(e) = constructor { | ||
686 | if id == e.local_id { | ||
687 | return true; | ||
688 | } | ||
689 | } | ||
690 | } | ||
691 | |||
692 | false | ||
693 | }), | ||
694 | } | ||
695 | } | ||
696 | |||
697 | fn enum_variant_matches(cx: &MatchCheckCtx, pat_id: PatId, enum_variant_id: EnumVariantId) -> bool { | ||
698 | Some(enum_variant_id.into()) == cx.infer.variant_resolution_for_pat(pat_id) | ||
699 | } | ||
700 | |||
701 | #[cfg(test)] | ||
702 | mod tests { | ||
703 | pub(super) use insta::assert_snapshot; | ||
704 | pub(super) use ra_db::fixture::WithFixture; | ||
705 | |||
706 | pub(super) use crate::test_db::TestDB; | ||
707 | |||
708 | pub(super) fn check_diagnostic_message(content: &str) -> String { | ||
709 | TestDB::with_single_file(content).0.diagnostics().0 | ||
710 | } | ||
711 | |||
712 | pub(super) fn check_diagnostic(content: &str) { | ||
713 | let diagnostic_count = TestDB::with_single_file(content).0.diagnostics().1; | ||
714 | |||
715 | assert_eq!(1, diagnostic_count, "no diagnostic reported"); | ||
716 | } | ||
717 | |||
718 | pub(super) fn check_no_diagnostic(content: &str) { | ||
719 | let diagnostic_count = TestDB::with_single_file(content).0.diagnostics().1; | ||
720 | |||
721 | assert_eq!(0, diagnostic_count, "expected no diagnostic, found one"); | ||
722 | } | ||
723 | |||
724 | #[test] | ||
725 | fn empty_tuple_no_arms_diagnostic_message() { | ||
726 | let content = r" | ||
727 | fn test_fn() { | ||
728 | match () { | ||
729 | } | ||
730 | } | ||
731 | "; | ||
732 | |||
733 | assert_snapshot!( | ||
734 | check_diagnostic_message(content), | ||
735 | @"\"()\": Missing match arm\n" | ||
736 | ); | ||
737 | } | ||
738 | |||
739 | #[test] | ||
740 | fn empty_tuple_no_arms() { | ||
741 | let content = r" | ||
742 | fn test_fn() { | ||
743 | match () { | ||
744 | } | ||
745 | } | ||
746 | "; | ||
747 | |||
748 | check_diagnostic(content); | ||
749 | } | ||
750 | |||
751 | #[test] | ||
752 | fn empty_tuple_wild() { | ||
753 | let content = r" | ||
754 | fn test_fn() { | ||
755 | match () { | ||
756 | _ => {} | ||
757 | } | ||
758 | } | ||
759 | "; | ||
760 | |||
761 | check_no_diagnostic(content); | ||
762 | } | ||
763 | |||
764 | #[test] | ||
765 | fn empty_tuple_no_diagnostic() { | ||
766 | let content = r" | ||
767 | fn test_fn() { | ||
768 | match () { | ||
769 | () => {} | ||
770 | } | ||
771 | } | ||
772 | "; | ||
773 | |||
774 | check_no_diagnostic(content); | ||
775 | } | ||
776 | |||
777 | #[test] | ||
778 | fn tuple_of_empty_tuple_no_arms() { | ||
779 | let content = r" | ||
780 | fn test_fn() { | ||
781 | match (()) { | ||
782 | } | ||
783 | } | ||
784 | "; | ||
785 | |||
786 | check_diagnostic(content); | ||
787 | } | ||
788 | |||
789 | #[test] | ||
790 | fn tuple_of_empty_tuple_no_diagnostic() { | ||
791 | let content = r" | ||
792 | fn test_fn() { | ||
793 | match (()) { | ||
794 | (()) => {} | ||
795 | } | ||
796 | } | ||
797 | "; | ||
798 | |||
799 | check_no_diagnostic(content); | ||
800 | } | ||
801 | |||
802 | #[test] | ||
803 | fn tuple_of_two_empty_tuple_no_arms() { | ||
804 | let content = r" | ||
805 | fn test_fn() { | ||
806 | match ((), ()) { | ||
807 | } | ||
808 | } | ||
809 | "; | ||
810 | |||
811 | check_diagnostic(content); | ||
812 | } | ||
813 | |||
814 | #[test] | ||
815 | fn tuple_of_two_empty_tuple_no_diagnostic() { | ||
816 | let content = r" | ||
817 | fn test_fn() { | ||
818 | match ((), ()) { | ||
819 | ((), ()) => {} | ||
820 | } | ||
821 | } | ||
822 | "; | ||
823 | |||
824 | check_no_diagnostic(content); | ||
825 | } | ||
826 | |||
827 | #[test] | ||
828 | fn bool_no_arms() { | ||
829 | let content = r" | ||
830 | fn test_fn() { | ||
831 | match false { | ||
832 | } | ||
833 | } | ||
834 | "; | ||
835 | |||
836 | check_diagnostic(content); | ||
837 | } | ||
838 | |||
839 | #[test] | ||
840 | fn bool_missing_arm() { | ||
841 | let content = r" | ||
842 | fn test_fn() { | ||
843 | match false { | ||
844 | true => {} | ||
845 | } | ||
846 | } | ||
847 | "; | ||
848 | |||
849 | check_diagnostic(content); | ||
850 | } | ||
851 | |||
852 | #[test] | ||
853 | fn bool_no_diagnostic() { | ||
854 | let content = r" | ||
855 | fn test_fn() { | ||
856 | match false { | ||
857 | true => {} | ||
858 | false => {} | ||
859 | } | ||
860 | } | ||
861 | "; | ||
862 | |||
863 | check_no_diagnostic(content); | ||
864 | } | ||
865 | |||
866 | #[test] | ||
867 | fn tuple_of_bools_no_arms() { | ||
868 | let content = r" | ||
869 | fn test_fn() { | ||
870 | match (false, true) { | ||
871 | } | ||
872 | } | ||
873 | "; | ||
874 | |||
875 | check_diagnostic(content); | ||
876 | } | ||
877 | |||
878 | #[test] | ||
879 | fn tuple_of_bools_missing_arms() { | ||
880 | let content = r" | ||
881 | fn test_fn() { | ||
882 | match (false, true) { | ||
883 | (true, true) => {}, | ||
884 | } | ||
885 | } | ||
886 | "; | ||
887 | |||
888 | check_diagnostic(content); | ||
889 | } | ||
890 | |||
891 | #[test] | ||
892 | fn tuple_of_bools_missing_arm() { | ||
893 | let content = r" | ||
894 | fn test_fn() { | ||
895 | match (false, true) { | ||
896 | (false, true) => {}, | ||
897 | (false, false) => {}, | ||
898 | (true, false) => {}, | ||
899 | } | ||
900 | } | ||
901 | "; | ||
902 | |||
903 | check_diagnostic(content); | ||
904 | } | ||
905 | |||
906 | #[test] | ||
907 | fn tuple_of_bools_with_wilds() { | ||
908 | let content = r" | ||
909 | fn test_fn() { | ||
910 | match (false, true) { | ||
911 | (false, _) => {}, | ||
912 | (true, false) => {}, | ||
913 | (_, true) => {}, | ||
914 | } | ||
915 | } | ||
916 | "; | ||
917 | |||
918 | check_no_diagnostic(content); | ||
919 | } | ||
920 | |||
921 | #[test] | ||
922 | fn tuple_of_bools_no_diagnostic() { | ||
923 | let content = r" | ||
924 | fn test_fn() { | ||
925 | match (false, true) { | ||
926 | (true, true) => {}, | ||
927 | (true, false) => {}, | ||
928 | (false, true) => {}, | ||
929 | (false, false) => {}, | ||
930 | } | ||
931 | } | ||
932 | "; | ||
933 | |||
934 | check_no_diagnostic(content); | ||
935 | } | ||
936 | |||
937 | #[test] | ||
938 | fn tuple_of_bools_binding_missing_arms() { | ||
939 | let content = r" | ||
940 | fn test_fn() { | ||
941 | match (false, true) { | ||
942 | (true, _x) => {}, | ||
943 | } | ||
944 | } | ||
945 | "; | ||
946 | |||
947 | check_diagnostic(content); | ||
948 | } | ||
949 | |||
950 | #[test] | ||
951 | fn tuple_of_bools_binding_no_diagnostic() { | ||
952 | let content = r" | ||
953 | fn test_fn() { | ||
954 | match (false, true) { | ||
955 | (true, _x) => {}, | ||
956 | (false, true) => {}, | ||
957 | (false, false) => {}, | ||
958 | } | ||
959 | } | ||
960 | "; | ||
961 | |||
962 | check_no_diagnostic(content); | ||
963 | } | ||
964 | |||
965 | #[test] | ||
966 | fn tuple_of_tuple_and_bools_no_arms() { | ||
967 | let content = r" | ||
968 | fn test_fn() { | ||
969 | match (false, ((), false)) { | ||
970 | } | ||
971 | } | ||
972 | "; | ||
973 | |||
974 | check_diagnostic(content); | ||
975 | } | ||
976 | |||
977 | #[test] | ||
978 | fn tuple_of_tuple_and_bools_missing_arms() { | ||
979 | let content = r" | ||
980 | fn test_fn() { | ||
981 | match (false, ((), false)) { | ||
982 | (true, ((), true)) => {}, | ||
983 | } | ||
984 | } | ||
985 | "; | ||
986 | |||
987 | check_diagnostic(content); | ||
988 | } | ||
989 | |||
990 | #[test] | ||
991 | fn tuple_of_tuple_and_bools_no_diagnostic() { | ||
992 | let content = r" | ||
993 | fn test_fn() { | ||
994 | match (false, ((), false)) { | ||
995 | (true, ((), true)) => {}, | ||
996 | (true, ((), false)) => {}, | ||
997 | (false, ((), true)) => {}, | ||
998 | (false, ((), false)) => {}, | ||
999 | } | ||
1000 | } | ||
1001 | "; | ||
1002 | |||
1003 | check_no_diagnostic(content); | ||
1004 | } | ||
1005 | |||
1006 | #[test] | ||
1007 | fn tuple_of_tuple_and_bools_wildcard_missing_arms() { | ||
1008 | let content = r" | ||
1009 | fn test_fn() { | ||
1010 | match (false, ((), false)) { | ||
1011 | (true, _) => {}, | ||
1012 | } | ||
1013 | } | ||
1014 | "; | ||
1015 | |||
1016 | check_diagnostic(content); | ||
1017 | } | ||
1018 | |||
1019 | #[test] | ||
1020 | fn tuple_of_tuple_and_bools_wildcard_no_diagnostic() { | ||
1021 | let content = r" | ||
1022 | fn test_fn() { | ||
1023 | match (false, ((), false)) { | ||
1024 | (true, ((), true)) => {}, | ||
1025 | (true, ((), false)) => {}, | ||
1026 | (false, _) => {}, | ||
1027 | } | ||
1028 | } | ||
1029 | "; | ||
1030 | |||
1031 | check_no_diagnostic(content); | ||
1032 | } | ||
1033 | |||
1034 | #[test] | ||
1035 | fn enum_no_arms() { | ||
1036 | let content = r" | ||
1037 | enum Either { | ||
1038 | A, | ||
1039 | B, | ||
1040 | } | ||
1041 | fn test_fn() { | ||
1042 | match Either::A { | ||
1043 | } | ||
1044 | } | ||
1045 | "; | ||
1046 | |||
1047 | check_diagnostic(content); | ||
1048 | } | ||
1049 | |||
1050 | #[test] | ||
1051 | fn enum_missing_arms() { | ||
1052 | let content = r" | ||
1053 | enum Either { | ||
1054 | A, | ||
1055 | B, | ||
1056 | } | ||
1057 | fn test_fn() { | ||
1058 | match Either::B { | ||
1059 | Either::A => {}, | ||
1060 | } | ||
1061 | } | ||
1062 | "; | ||
1063 | |||
1064 | check_diagnostic(content); | ||
1065 | } | ||
1066 | |||
1067 | #[test] | ||
1068 | fn enum_no_diagnostic() { | ||
1069 | let content = r" | ||
1070 | enum Either { | ||
1071 | A, | ||
1072 | B, | ||
1073 | } | ||
1074 | fn test_fn() { | ||
1075 | match Either::B { | ||
1076 | Either::A => {}, | ||
1077 | Either::B => {}, | ||
1078 | } | ||
1079 | } | ||
1080 | "; | ||
1081 | |||
1082 | check_no_diagnostic(content); | ||
1083 | } | ||
1084 | |||
1085 | #[test] | ||
1086 | fn enum_ref_missing_arms() { | ||
1087 | let content = r" | ||
1088 | enum Either { | ||
1089 | A, | ||
1090 | B, | ||
1091 | } | ||
1092 | fn test_fn() { | ||
1093 | match &Either::B { | ||
1094 | Either::A => {}, | ||
1095 | } | ||
1096 | } | ||
1097 | "; | ||
1098 | |||
1099 | check_diagnostic(content); | ||
1100 | } | ||
1101 | |||
1102 | #[test] | ||
1103 | fn enum_ref_no_diagnostic() { | ||
1104 | let content = r" | ||
1105 | enum Either { | ||
1106 | A, | ||
1107 | B, | ||
1108 | } | ||
1109 | fn test_fn() { | ||
1110 | match &Either::B { | ||
1111 | Either::A => {}, | ||
1112 | Either::B => {}, | ||
1113 | } | ||
1114 | } | ||
1115 | "; | ||
1116 | |||
1117 | check_no_diagnostic(content); | ||
1118 | } | ||
1119 | |||
1120 | #[test] | ||
1121 | fn enum_containing_bool_no_arms() { | ||
1122 | let content = r" | ||
1123 | enum Either { | ||
1124 | A(bool), | ||
1125 | B, | ||
1126 | } | ||
1127 | fn test_fn() { | ||
1128 | match Either::B { | ||
1129 | } | ||
1130 | } | ||
1131 | "; | ||
1132 | |||
1133 | check_diagnostic(content); | ||
1134 | } | ||
1135 | |||
1136 | #[test] | ||
1137 | fn enum_containing_bool_missing_arms() { | ||
1138 | let content = r" | ||
1139 | enum Either { | ||
1140 | A(bool), | ||
1141 | B, | ||
1142 | } | ||
1143 | fn test_fn() { | ||
1144 | match Either::B { | ||
1145 | Either::A(true) => (), | ||
1146 | Either::B => (), | ||
1147 | } | ||
1148 | } | ||
1149 | "; | ||
1150 | |||
1151 | check_diagnostic(content); | ||
1152 | } | ||
1153 | |||
1154 | #[test] | ||
1155 | fn enum_containing_bool_no_diagnostic() { | ||
1156 | let content = r" | ||
1157 | enum Either { | ||
1158 | A(bool), | ||
1159 | B, | ||
1160 | } | ||
1161 | fn test_fn() { | ||
1162 | match Either::B { | ||
1163 | Either::A(true) => (), | ||
1164 | Either::A(false) => (), | ||
1165 | Either::B => (), | ||
1166 | } | ||
1167 | } | ||
1168 | "; | ||
1169 | |||
1170 | check_no_diagnostic(content); | ||
1171 | } | ||
1172 | |||
1173 | #[test] | ||
1174 | fn enum_containing_bool_with_wild_no_diagnostic() { | ||
1175 | let content = r" | ||
1176 | enum Either { | ||
1177 | A(bool), | ||
1178 | B, | ||
1179 | } | ||
1180 | fn test_fn() { | ||
1181 | match Either::B { | ||
1182 | Either::B => (), | ||
1183 | _ => (), | ||
1184 | } | ||
1185 | } | ||
1186 | "; | ||
1187 | |||
1188 | check_no_diagnostic(content); | ||
1189 | } | ||
1190 | |||
1191 | #[test] | ||
1192 | fn enum_containing_bool_with_wild_2_no_diagnostic() { | ||
1193 | let content = r" | ||
1194 | enum Either { | ||
1195 | A(bool), | ||
1196 | B, | ||
1197 | } | ||
1198 | fn test_fn() { | ||
1199 | match Either::B { | ||
1200 | Either::A(_) => (), | ||
1201 | Either::B => (), | ||
1202 | } | ||
1203 | } | ||
1204 | "; | ||
1205 | |||
1206 | check_no_diagnostic(content); | ||
1207 | } | ||
1208 | |||
1209 | #[test] | ||
1210 | fn enum_different_sizes_missing_arms() { | ||
1211 | let content = r" | ||
1212 | enum Either { | ||
1213 | A(bool), | ||
1214 | B(bool, bool), | ||
1215 | } | ||
1216 | fn test_fn() { | ||
1217 | match Either::A(false) { | ||
1218 | Either::A(_) => (), | ||
1219 | Either::B(false, _) => (), | ||
1220 | } | ||
1221 | } | ||
1222 | "; | ||
1223 | |||
1224 | check_diagnostic(content); | ||
1225 | } | ||
1226 | |||
1227 | #[test] | ||
1228 | fn enum_different_sizes_no_diagnostic() { | ||
1229 | let content = r" | ||
1230 | enum Either { | ||
1231 | A(bool), | ||
1232 | B(bool, bool), | ||
1233 | } | ||
1234 | fn test_fn() { | ||
1235 | match Either::A(false) { | ||
1236 | Either::A(_) => (), | ||
1237 | Either::B(true, _) => (), | ||
1238 | Either::B(false, _) => (), | ||
1239 | } | ||
1240 | } | ||
1241 | "; | ||
1242 | |||
1243 | check_no_diagnostic(content); | ||
1244 | } | ||
1245 | |||
1246 | #[test] | ||
1247 | fn or_no_diagnostic() { | ||
1248 | let content = r" | ||
1249 | enum Either { | ||
1250 | A(bool), | ||
1251 | B(bool, bool), | ||
1252 | } | ||
1253 | fn test_fn() { | ||
1254 | match Either::A(false) { | ||
1255 | Either::A(true) | Either::A(false) => (), | ||
1256 | Either::B(true, _) => (), | ||
1257 | Either::B(false, _) => (), | ||
1258 | } | ||
1259 | } | ||
1260 | "; | ||
1261 | |||
1262 | check_no_diagnostic(content); | ||
1263 | } | ||
1264 | |||
1265 | #[test] | ||
1266 | fn tuple_of_enum_no_diagnostic() { | ||
1267 | let content = r" | ||
1268 | enum Either { | ||
1269 | A(bool), | ||
1270 | B(bool, bool), | ||
1271 | } | ||
1272 | enum Either2 { | ||
1273 | C, | ||
1274 | D, | ||
1275 | } | ||
1276 | fn test_fn() { | ||
1277 | match (Either::A(false), Either2::C) { | ||
1278 | (Either::A(true), _) | (Either::A(false), _) => (), | ||
1279 | (Either::B(true, _), Either2::C) => (), | ||
1280 | (Either::B(false, _), Either2::C) => (), | ||
1281 | (Either::B(_, _), Either2::D) => (), | ||
1282 | } | ||
1283 | } | ||
1284 | "; | ||
1285 | |||
1286 | check_no_diagnostic(content); | ||
1287 | } | ||
1288 | |||
1289 | #[test] | ||
1290 | fn mismatched_types() { | ||
1291 | let content = r" | ||
1292 | enum Either { | ||
1293 | A, | ||
1294 | B, | ||
1295 | } | ||
1296 | enum Either2 { | ||
1297 | C, | ||
1298 | D, | ||
1299 | } | ||
1300 | fn test_fn() { | ||
1301 | match Either::A { | ||
1302 | Either2::C => (), | ||
1303 | Either2::D => (), | ||
1304 | } | ||
1305 | } | ||
1306 | "; | ||
1307 | |||
1308 | // Match arms with the incorrect type are filtered out. | ||
1309 | check_diagnostic(content); | ||
1310 | } | ||
1311 | |||
1312 | #[test] | ||
1313 | fn mismatched_types_with_different_arity() { | ||
1314 | let content = r" | ||
1315 | fn test_fn() { | ||
1316 | match (true, false) { | ||
1317 | (true, false, true) => (), | ||
1318 | (true) => (), | ||
1319 | } | ||
1320 | } | ||
1321 | "; | ||
1322 | |||
1323 | // Match arms with the incorrect type are filtered out. | ||
1324 | check_diagnostic(content); | ||
1325 | } | ||
1326 | |||
1327 | #[test] | ||
1328 | fn enum_not_in_scope() { | ||
1329 | let content = r" | ||
1330 | fn test_fn() { | ||
1331 | match Foo::Bar { | ||
1332 | Foo::Baz => (), | ||
1333 | } | ||
1334 | } | ||
1335 | "; | ||
1336 | |||
1337 | // The enum is not in scope so we don't perform exhaustiveness | ||
1338 | // checking, but we want to be sure we don't panic here (and | ||
1339 | // we don't create a diagnostic). | ||
1340 | check_no_diagnostic(content); | ||
1341 | } | ||
1342 | } | ||
1343 | |||
1344 | #[cfg(test)] | ||
1345 | mod false_negatives { | ||
1346 | //! The implementation of match checking here is a work in progress. As we roll this out, we | ||
1347 | //! prefer false negatives to false positives (ideally there would be no false positives). This | ||
1348 | //! test module should document known false negatives. Eventually we will have a complete | ||
1349 | //! implementation of match checking and this module will be empty. | ||
1350 | //! | ||
1351 | //! The reasons for documenting known false negatives: | ||
1352 | //! | ||
1353 | //! 1. It acts as a backlog of work that can be done to improve the behavior of the system. | ||
1354 | //! 2. It ensures the code doesn't panic when handling these cases. | ||
1355 | |||
1356 | use super::tests::*; | ||
1357 | |||
1358 | #[test] | ||
1359 | fn integers() { | ||
1360 | let content = r" | ||
1361 | fn test_fn() { | ||
1362 | match 5 { | ||
1363 | 10 => (), | ||
1364 | 11..20 => (), | ||
1365 | } | ||
1366 | } | ||
1367 | "; | ||
1368 | |||
1369 | // This is a false negative. | ||
1370 | // We don't currently check integer exhaustiveness. | ||
1371 | check_no_diagnostic(content); | ||
1372 | } | ||
1373 | |||
1374 | #[test] | ||
1375 | fn enum_record() { | ||
1376 | let content = r" | ||
1377 | enum Either { | ||
1378 | A { foo: u32 }, | ||
1379 | B, | ||
1380 | } | ||
1381 | fn test_fn() { | ||
1382 | match Either::B { | ||
1383 | Either::A { foo: 5 } => (), | ||
1384 | } | ||
1385 | } | ||
1386 | "; | ||
1387 | |||
1388 | // This is a false negative. | ||
1389 | // We don't currently handle enum record types. | ||
1390 | check_no_diagnostic(content); | ||
1391 | } | ||
1392 | |||
1393 | #[test] | ||
1394 | fn internal_or() { | ||
1395 | let content = r" | ||
1396 | fn test_fn() { | ||
1397 | enum Either { | ||
1398 | A(bool), | ||
1399 | B, | ||
1400 | } | ||
1401 | match Either::B { | ||
1402 | Either::A(true | false) => (), | ||
1403 | } | ||
1404 | } | ||
1405 | "; | ||
1406 | |||
1407 | // This is a false negative. | ||
1408 | // We do not currently handle patterns with internal `or`s. | ||
1409 | check_no_diagnostic(content); | ||
1410 | } | ||
1411 | } | ||
diff --git a/crates/ra_hir_ty/src/diagnostics.rs b/crates/ra_hir_ty/src/diagnostics.rs index 0f8522021..8cbce1168 100644 --- a/crates/ra_hir_ty/src/diagnostics.rs +++ b/crates/ra_hir_ty/src/diagnostics.rs | |||
@@ -6,7 +6,7 @@ use hir_expand::{db::AstDatabase, name::Name, HirFileId, InFile}; | |||
6 | use ra_syntax::{ast, AstNode, AstPtr, SyntaxNodePtr}; | 6 | use ra_syntax::{ast, AstNode, AstPtr, SyntaxNodePtr}; |
7 | use stdx::format_to; | 7 | use stdx::format_to; |
8 | 8 | ||
9 | pub use hir_def::diagnostics::UnresolvedModule; | 9 | pub use hir_def::{diagnostics::UnresolvedModule, expr::MatchArm}; |
10 | pub use hir_expand::diagnostics::{AstDiagnostic, Diagnostic, DiagnosticSink}; | 10 | pub use hir_expand::diagnostics::{AstDiagnostic, Diagnostic, DiagnosticSink}; |
11 | 11 | ||
12 | #[derive(Debug)] | 12 | #[derive(Debug)] |
@@ -63,6 +63,25 @@ impl AstDiagnostic for MissingFields { | |||
63 | } | 63 | } |
64 | 64 | ||
65 | #[derive(Debug)] | 65 | #[derive(Debug)] |
66 | pub struct MissingMatchArms { | ||
67 | pub file: HirFileId, | ||
68 | pub match_expr: AstPtr<ast::Expr>, | ||
69 | pub arms: AstPtr<ast::MatchArmList>, | ||
70 | } | ||
71 | |||
72 | impl Diagnostic for MissingMatchArms { | ||
73 | fn message(&self) -> String { | ||
74 | String::from("Missing match arm") | ||
75 | } | ||
76 | fn source(&self) -> InFile<SyntaxNodePtr> { | ||
77 | InFile { file_id: self.file, value: self.match_expr.into() } | ||
78 | } | ||
79 | fn as_any(&self) -> &(dyn Any + Send + 'static) { | ||
80 | self | ||
81 | } | ||
82 | } | ||
83 | |||
84 | #[derive(Debug)] | ||
66 | pub struct MissingOkInTailExpr { | 85 | pub struct MissingOkInTailExpr { |
67 | pub file: HirFileId, | 86 | pub file: HirFileId, |
68 | pub expr: AstPtr<ast::Expr>, | 87 | pub expr: AstPtr<ast::Expr>, |
diff --git a/crates/ra_hir_ty/src/expr.rs b/crates/ra_hir_ty/src/expr.rs index eb1209d08..6547eedae 100644 --- a/crates/ra_hir_ty/src/expr.rs +++ b/crates/ra_hir_ty/src/expr.rs | |||
@@ -13,9 +13,10 @@ use rustc_hash::FxHashSet; | |||
13 | 13 | ||
14 | use crate::{ | 14 | use crate::{ |
15 | db::HirDatabase, | 15 | db::HirDatabase, |
16 | diagnostics::{MissingFields, MissingOkInTailExpr}, | 16 | diagnostics::{MissingFields, MissingMatchArms, MissingOkInTailExpr}, |
17 | utils::variant_data, | 17 | utils::variant_data, |
18 | ApplicationTy, InferenceResult, Ty, TypeCtor, | 18 | ApplicationTy, InferenceResult, Ty, TypeCtor, |
19 | _match::{is_useful, MatchCheckCtx, Matrix, PatStack, Usefulness}, | ||
19 | }; | 20 | }; |
20 | 21 | ||
21 | pub use hir_def::{ | 22 | pub use hir_def::{ |
@@ -51,15 +52,99 @@ impl<'a, 'b> ExprValidator<'a, 'b> { | |||
51 | for e in body.exprs.iter() { | 52 | for e in body.exprs.iter() { |
52 | if let (id, Expr::RecordLit { path, fields, spread }) = e { | 53 | if let (id, Expr::RecordLit { path, fields, spread }) = e { |
53 | self.validate_record_literal(id, path, fields, *spread, db); | 54 | self.validate_record_literal(id, path, fields, *spread, db); |
55 | } else if let (id, Expr::Match { expr, arms }) = e { | ||
56 | self.validate_match(id, *expr, arms, db, self.infer.clone()); | ||
54 | } | 57 | } |
55 | } | 58 | } |
56 | 59 | ||
57 | let body_expr = &body[body.body_expr]; | 60 | let body_expr = &body[body.body_expr]; |
58 | if let Expr::Block { statements: _, tail: Some(t) } = body_expr { | 61 | if let Expr::Block { tail: Some(t), .. } = body_expr { |
59 | self.validate_results_in_tail_expr(body.body_expr, *t, db); | 62 | self.validate_results_in_tail_expr(body.body_expr, *t, db); |
60 | } | 63 | } |
61 | } | 64 | } |
62 | 65 | ||
66 | fn validate_match( | ||
67 | &mut self, | ||
68 | id: ExprId, | ||
69 | match_expr: ExprId, | ||
70 | arms: &[MatchArm], | ||
71 | db: &dyn HirDatabase, | ||
72 | infer: Arc<InferenceResult>, | ||
73 | ) { | ||
74 | let (body, source_map): (Arc<Body>, Arc<BodySourceMap>) = | ||
75 | db.body_with_source_map(self.func.into()); | ||
76 | |||
77 | let match_expr_ty = match infer.type_of_expr.get(match_expr) { | ||
78 | Some(ty) => ty, | ||
79 | // If we can't resolve the type of the match expression | ||
80 | // we cannot perform exhaustiveness checks. | ||
81 | None => return, | ||
82 | }; | ||
83 | |||
84 | let cx = MatchCheckCtx { body, infer: infer.clone(), db }; | ||
85 | let pats = arms.iter().map(|arm| arm.pat); | ||
86 | |||
87 | let mut seen = Matrix::empty(); | ||
88 | for pat in pats { | ||
89 | // We skip any patterns whose type we cannot resolve. | ||
90 | // | ||
91 | // This could lead to false positives in this diagnostic, so | ||
92 | // it might be better to skip the entire diagnostic if we either | ||
93 | // cannot resolve a match arm or determine that the match arm has | ||
94 | // the wrong type. | ||
95 | if let Some(pat_ty) = infer.type_of_pat.get(pat) { | ||
96 | // We only include patterns whose type matches the type | ||
97 | // of the match expression. If we had a InvalidMatchArmPattern | ||
98 | // diagnostic or similar we could raise that in an else | ||
99 | // block here. | ||
100 | // | ||
101 | // When comparing the types, we also have to consider that rustc | ||
102 | // will automatically de-reference the match expression type if | ||
103 | // necessary. | ||
104 | // | ||
105 | // FIXME we should use the type checker for this. | ||
106 | if pat_ty == match_expr_ty | ||
107 | || match_expr_ty | ||
108 | .as_reference() | ||
109 | .map(|(match_expr_ty, _)| match_expr_ty == pat_ty) | ||
110 | .unwrap_or(false) | ||
111 | { | ||
112 | // If we had a NotUsefulMatchArm diagnostic, we could | ||
113 | // check the usefulness of each pattern as we added it | ||
114 | // to the matrix here. | ||
115 | let v = PatStack::from_pattern(pat); | ||
116 | seen.push(&cx, v); | ||
117 | } | ||
118 | } | ||
119 | } | ||
120 | |||
121 | match is_useful(&cx, &seen, &PatStack::from_wild()) { | ||
122 | Ok(Usefulness::Useful) => (), | ||
123 | // if a wildcard pattern is not useful, then all patterns are covered | ||
124 | Ok(Usefulness::NotUseful) => return, | ||
125 | // this path is for unimplemented checks, so we err on the side of not | ||
126 | // reporting any errors | ||
127 | _ => return, | ||
128 | } | ||
129 | |||
130 | if let Ok(source_ptr) = source_map.expr_syntax(id) { | ||
131 | if let Some(expr) = source_ptr.value.left() { | ||
132 | let root = source_ptr.file_syntax(db.upcast()); | ||
133 | if let ast::Expr::MatchExpr(match_expr) = expr.to_node(&root) { | ||
134 | if let (Some(match_expr), Some(arms)) = | ||
135 | (match_expr.expr(), match_expr.match_arm_list()) | ||
136 | { | ||
137 | self.sink.push(MissingMatchArms { | ||
138 | file: source_ptr.file_id, | ||
139 | match_expr: AstPtr::new(&match_expr), | ||
140 | arms: AstPtr::new(&arms), | ||
141 | }) | ||
142 | } | ||
143 | } | ||
144 | } | ||
145 | } | ||
146 | } | ||
147 | |||
63 | fn validate_record_literal( | 148 | fn validate_record_literal( |
64 | &mut self, | 149 | &mut self, |
65 | id: ExprId, | 150 | id: ExprId, |
diff --git a/crates/ra_hir_ty/src/infer/pat.rs b/crates/ra_hir_ty/src/infer/pat.rs index 86acd27f8..69bbb4307 100644 --- a/crates/ra_hir_ty/src/infer/pat.rs +++ b/crates/ra_hir_ty/src/infer/pat.rs | |||
@@ -21,9 +21,13 @@ impl<'a> InferenceContext<'a> { | |||
21 | subpats: &[PatId], | 21 | subpats: &[PatId], |
22 | expected: &Ty, | 22 | expected: &Ty, |
23 | default_bm: BindingMode, | 23 | default_bm: BindingMode, |
24 | id: PatId, | ||
24 | ) -> Ty { | 25 | ) -> Ty { |
25 | let (ty, def) = self.resolve_variant(path); | 26 | let (ty, def) = self.resolve_variant(path); |
26 | let var_data = def.map(|it| variant_data(self.db.upcast(), it)); | 27 | let var_data = def.map(|it| variant_data(self.db.upcast(), it)); |
28 | if let Some(variant) = def { | ||
29 | self.write_variant_resolution(id.into(), variant); | ||
30 | } | ||
27 | self.unify(&ty, expected); | 31 | self.unify(&ty, expected); |
28 | 32 | ||
29 | let substs = ty.substs().unwrap_or_else(Substs::empty); | 33 | let substs = ty.substs().unwrap_or_else(Substs::empty); |
@@ -152,7 +156,7 @@ impl<'a> InferenceContext<'a> { | |||
152 | Ty::apply_one(TypeCtor::Ref(*mutability), subty) | 156 | Ty::apply_one(TypeCtor::Ref(*mutability), subty) |
153 | } | 157 | } |
154 | Pat::TupleStruct { path: p, args: subpats } => { | 158 | Pat::TupleStruct { path: p, args: subpats } => { |
155 | self.infer_tuple_struct_pat(p.as_ref(), subpats, expected, default_bm) | 159 | self.infer_tuple_struct_pat(p.as_ref(), subpats, expected, default_bm, pat) |
156 | } | 160 | } |
157 | Pat::Record { path: p, args: fields } => { | 161 | Pat::Record { path: p, args: fields } => { |
158 | self.infer_record_pat(p.as_ref(), fields, expected, default_bm, pat) | 162 | self.infer_record_pat(p.as_ref(), fields, expected, default_bm, pat) |
diff --git a/crates/ra_hir_ty/src/infer/path.rs b/crates/ra_hir_ty/src/infer/path.rs index 318652c61..2b6bc0f79 100644 --- a/crates/ra_hir_ty/src/infer/path.rs +++ b/crates/ra_hir_ty/src/infer/path.rs | |||
@@ -67,8 +67,16 @@ impl<'a> InferenceContext<'a> { | |||
67 | ValueNs::FunctionId(it) => it.into(), | 67 | ValueNs::FunctionId(it) => it.into(), |
68 | ValueNs::ConstId(it) => it.into(), | 68 | ValueNs::ConstId(it) => it.into(), |
69 | ValueNs::StaticId(it) => it.into(), | 69 | ValueNs::StaticId(it) => it.into(), |
70 | ValueNs::StructId(it) => it.into(), | 70 | ValueNs::StructId(it) => { |
71 | ValueNs::EnumVariantId(it) => it.into(), | 71 | self.write_variant_resolution(id, it.into()); |
72 | |||
73 | it.into() | ||
74 | } | ||
75 | ValueNs::EnumVariantId(it) => { | ||
76 | self.write_variant_resolution(id, it.into()); | ||
77 | |||
78 | it.into() | ||
79 | } | ||
72 | }; | 80 | }; |
73 | 81 | ||
74 | let ty = self.db.value_ty(typable); | 82 | let ty = self.db.value_ty(typable); |
diff --git a/crates/ra_hir_ty/src/lib.rs b/crates/ra_hir_ty/src/lib.rs index a9022dee7..18f74d3b1 100644 --- a/crates/ra_hir_ty/src/lib.rs +++ b/crates/ra_hir_ty/src/lib.rs | |||
@@ -1,6 +1,11 @@ | |||
1 | //! The type system. We currently use this to infer types for completion, hover | 1 | //! The type system. We currently use this to infer types for completion, hover |
2 | //! information and various assists. | 2 | //! information and various assists. |
3 | 3 | ||
4 | #[allow(unused)] | ||
5 | macro_rules! eprintln { | ||
6 | ($($tt:tt)*) => { stdx::eprintln!($($tt)*) }; | ||
7 | } | ||
8 | |||
4 | macro_rules! impl_froms { | 9 | macro_rules! impl_froms { |
5 | ($e:ident: $($v:ident $(($($sv:ident),*))?),*) => { | 10 | ($e:ident: $($v:ident $(($($sv:ident),*))?),*) => { |
6 | $( | 11 | $( |
@@ -38,6 +43,7 @@ mod tests; | |||
38 | #[cfg(test)] | 43 | #[cfg(test)] |
39 | mod test_db; | 44 | mod test_db; |
40 | mod marks; | 45 | mod marks; |
46 | mod _match; | ||
41 | 47 | ||
42 | use std::ops::Deref; | 48 | use std::ops::Deref; |
43 | use std::sync::Arc; | 49 | use std::sync::Arc; |
@@ -855,7 +861,8 @@ pub trait TypeWalk { | |||
855 | ); | 861 | ); |
856 | self | 862 | self |
857 | } | 863 | } |
858 | // /// Shifts up debruijn indices of `Ty::Bound` vars by `n`. | 864 | |
865 | /// Shifts up debruijn indices of `Ty::Bound` vars by `n`. | ||
859 | fn shift_bound_vars(self, n: DebruijnIndex) -> Self | 866 | fn shift_bound_vars(self, n: DebruijnIndex) -> Self |
860 | where | 867 | where |
861 | Self: Sized, | 868 | Self: Sized, |
diff --git a/crates/ra_hir_ty/src/test_db.rs b/crates/ra_hir_ty/src/test_db.rs index 208096aab..3a4d58bf9 100644 --- a/crates/ra_hir_ty/src/test_db.rs +++ b/crates/ra_hir_ty/src/test_db.rs | |||
@@ -105,8 +105,9 @@ impl TestDB { | |||
105 | } | 105 | } |
106 | 106 | ||
107 | // FIXME: don't duplicate this | 107 | // FIXME: don't duplicate this |
108 | pub fn diagnostics(&self) -> String { | 108 | pub fn diagnostics(&self) -> (String, u32) { |
109 | let mut buf = String::new(); | 109 | let mut buf = String::new(); |
110 | let mut count = 0; | ||
110 | let crate_graph = self.crate_graph(); | 111 | let crate_graph = self.crate_graph(); |
111 | for krate in crate_graph.iter() { | 112 | for krate in crate_graph.iter() { |
112 | let crate_def_map = self.crate_def_map(krate); | 113 | let crate_def_map = self.crate_def_map(krate); |
@@ -133,13 +134,14 @@ impl TestDB { | |||
133 | let infer = self.infer(f.into()); | 134 | let infer = self.infer(f.into()); |
134 | let mut sink = DiagnosticSink::new(|d| { | 135 | let mut sink = DiagnosticSink::new(|d| { |
135 | format_to!(buf, "{:?}: {}\n", d.syntax_node(self).text(), d.message()); | 136 | format_to!(buf, "{:?}: {}\n", d.syntax_node(self).text(), d.message()); |
137 | count += 1; | ||
136 | }); | 138 | }); |
137 | infer.add_diagnostics(self, f, &mut sink); | 139 | infer.add_diagnostics(self, f, &mut sink); |
138 | let mut validator = ExprValidator::new(f, infer, &mut sink); | 140 | let mut validator = ExprValidator::new(f, infer, &mut sink); |
139 | validator.validate_body(self); | 141 | validator.validate_body(self); |
140 | } | 142 | } |
141 | } | 143 | } |
142 | buf | 144 | (buf, count) |
143 | } | 145 | } |
144 | } | 146 | } |
145 | 147 | ||
diff --git a/crates/ra_hir_ty/src/tests.rs b/crates/ra_hir_ty/src/tests.rs index c3d793cc2..e6ac0aec3 100644 --- a/crates/ra_hir_ty/src/tests.rs +++ b/crates/ra_hir_ty/src/tests.rs | |||
@@ -309,7 +309,8 @@ fn no_such_field_diagnostics() { | |||
309 | } | 309 | } |
310 | ", | 310 | ", |
311 | ) | 311 | ) |
312 | .diagnostics(); | 312 | .diagnostics() |
313 | .0; | ||
313 | 314 | ||
314 | assert_snapshot!(diagnostics, @r###" | 315 | assert_snapshot!(diagnostics, @r###" |
315 | "baz: 62": no such field | 316 | "baz: 62": no such field |
diff --git a/crates/ra_hir_ty/src/tests/traits.rs b/crates/ra_hir_ty/src/tests/traits.rs index 081aa943a..22ae6ca90 100644 --- a/crates/ra_hir_ty/src/tests/traits.rs +++ b/crates/ra_hir_ty/src/tests/traits.rs | |||
@@ -2021,3 +2021,28 @@ fn main() { | |||
2021 | "### | 2021 | "### |
2022 | ); | 2022 | ); |
2023 | } | 2023 | } |
2024 | |||
2025 | #[test] | ||
2026 | fn dyn_trait_through_chalk() { | ||
2027 | let t = type_at( | ||
2028 | r#" | ||
2029 | //- /main.rs | ||
2030 | struct Box<T> {} | ||
2031 | #[lang = "deref"] | ||
2032 | trait Deref { | ||
2033 | type Target; | ||
2034 | } | ||
2035 | impl<T> Deref for Box<T> { | ||
2036 | type Target = T; | ||
2037 | } | ||
2038 | trait Trait { | ||
2039 | fn foo(&self); | ||
2040 | } | ||
2041 | |||
2042 | fn test(x: Box<dyn Trait>) { | ||
2043 | x.foo()<|>; | ||
2044 | } | ||
2045 | "#, | ||
2046 | ); | ||
2047 | assert_eq!(t, "()"); | ||
2048 | } | ||
diff --git a/crates/ra_hir_ty/src/traits/chalk.rs b/crates/ra_hir_ty/src/traits/chalk.rs index 53ce362ea..1bc0f0713 100644 --- a/crates/ra_hir_ty/src/traits/chalk.rs +++ b/crates/ra_hir_ty/src/traits/chalk.rs | |||
@@ -427,7 +427,12 @@ impl ToChalk for GenericPredicate { | |||
427 | db: &dyn HirDatabase, | 427 | db: &dyn HirDatabase, |
428 | where_clause: chalk_ir::QuantifiedWhereClause<Interner>, | 428 | where_clause: chalk_ir::QuantifiedWhereClause<Interner>, |
429 | ) -> GenericPredicate { | 429 | ) -> GenericPredicate { |
430 | match where_clause.value { | 430 | // we don't produce any where clauses with binders and can't currently deal with them |
431 | match where_clause | ||
432 | .value | ||
433 | .shifted_out(&Interner) | ||
434 | .expect("unexpected bound vars in where clause") | ||
435 | { | ||
431 | chalk_ir::WhereClause::Implemented(tr) => { | 436 | chalk_ir::WhereClause::Implemented(tr) => { |
432 | GenericPredicate::Implemented(from_chalk(db, tr)) | 437 | GenericPredicate::Implemented(from_chalk(db, tr)) |
433 | } | 438 | } |