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-rw-r--r--crates/ra_hir/src/ty/infer/pat.rs183
1 files changed, 0 insertions, 183 deletions
diff --git a/crates/ra_hir/src/ty/infer/pat.rs b/crates/ra_hir/src/ty/infer/pat.rs
deleted file mode 100644
index 641d61e87..000000000
--- a/crates/ra_hir/src/ty/infer/pat.rs
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@@ -1,183 +0,0 @@
1//! Type inference for patterns.
2
3use std::iter::repeat;
4use std::sync::Arc;
5
6use test_utils::tested_by;
7
8use super::{BindingMode, InferenceContext};
9use crate::{
10 db::HirDatabase,
11 expr::{BindingAnnotation, Pat, PatId, RecordFieldPat},
12 ty::{Mutability, Substs, Ty, TypeCtor, TypeWalk},
13 Name, Path,
14};
15
16impl<'a, D: HirDatabase> InferenceContext<'a, D> {
17 fn infer_tuple_struct_pat(
18 &mut self,
19 path: Option<&Path>,
20 subpats: &[PatId],
21 expected: &Ty,
22 default_bm: BindingMode,
23 ) -> Ty {
24 let (ty, def) = self.resolve_variant(path);
25
26 self.unify(&ty, expected);
27
28 let substs = ty.substs().unwrap_or_else(Substs::empty);
29
30 let field_tys = def.map(|it| self.db.field_types(it.into())).unwrap_or_default();
31 for (i, &subpat) in subpats.iter().enumerate() {
32 let expected_ty = def
33 .and_then(|d| d.field(self.db, &Name::new_tuple_field(i)))
34 .map_or(Ty::Unknown, |field| field_tys[field.id].clone())
35 .subst(&substs);
36 let expected_ty = self.normalize_associated_types_in(expected_ty);
37 self.infer_pat(subpat, &expected_ty, default_bm);
38 }
39
40 ty
41 }
42
43 fn infer_record_pat(
44 &mut self,
45 path: Option<&Path>,
46 subpats: &[RecordFieldPat],
47 expected: &Ty,
48 default_bm: BindingMode,
49 id: PatId,
50 ) -> Ty {
51 let (ty, def) = self.resolve_variant(path);
52 if let Some(variant) = def {
53 self.write_variant_resolution(id.into(), variant);
54 }
55
56 self.unify(&ty, expected);
57
58 let substs = ty.substs().unwrap_or_else(Substs::empty);
59
60 let field_tys = def.map(|it| self.db.field_types(it.into())).unwrap_or_default();
61 for subpat in subpats {
62 let matching_field = def.and_then(|it| it.field(self.db, &subpat.name));
63 let expected_ty = matching_field
64 .map_or(Ty::Unknown, |field| field_tys[field.id].clone())
65 .subst(&substs);
66 let expected_ty = self.normalize_associated_types_in(expected_ty);
67 self.infer_pat(subpat.pat, &expected_ty, default_bm);
68 }
69
70 ty
71 }
72
73 pub(super) fn infer_pat(
74 &mut self,
75 pat: PatId,
76 mut expected: &Ty,
77 mut default_bm: BindingMode,
78 ) -> Ty {
79 let body = Arc::clone(&self.body); // avoid borrow checker problem
80
81 let is_non_ref_pat = match &body[pat] {
82 Pat::Tuple(..)
83 | Pat::TupleStruct { .. }
84 | Pat::Record { .. }
85 | Pat::Range { .. }
86 | Pat::Slice { .. } => true,
87 // FIXME: Path/Lit might actually evaluate to ref, but inference is unimplemented.
88 Pat::Path(..) | Pat::Lit(..) => true,
89 Pat::Wild | Pat::Bind { .. } | Pat::Ref { .. } | Pat::Missing => false,
90 };
91 if is_non_ref_pat {
92 while let Some((inner, mutability)) = expected.as_reference() {
93 expected = inner;
94 default_bm = match default_bm {
95 BindingMode::Move => BindingMode::Ref(mutability),
96 BindingMode::Ref(Mutability::Shared) => BindingMode::Ref(Mutability::Shared),
97 BindingMode::Ref(Mutability::Mut) => BindingMode::Ref(mutability),
98 }
99 }
100 } else if let Pat::Ref { .. } = &body[pat] {
101 tested_by!(match_ergonomics_ref);
102 // When you encounter a `&pat` pattern, reset to Move.
103 // This is so that `w` is by value: `let (_, &w) = &(1, &2);`
104 default_bm = BindingMode::Move;
105 }
106
107 // Lose mutability.
108 let default_bm = default_bm;
109 let expected = expected;
110
111 let ty = match &body[pat] {
112 Pat::Tuple(ref args) => {
113 let expectations = match expected.as_tuple() {
114 Some(parameters) => &*parameters.0,
115 _ => &[],
116 };
117 let expectations_iter = expectations.iter().chain(repeat(&Ty::Unknown));
118
119 let inner_tys = args
120 .iter()
121 .zip(expectations_iter)
122 .map(|(&pat, ty)| self.infer_pat(pat, ty, default_bm))
123 .collect();
124
125 Ty::apply(TypeCtor::Tuple { cardinality: args.len() as u16 }, Substs(inner_tys))
126 }
127 Pat::Ref { pat, mutability } => {
128 let expectation = match expected.as_reference() {
129 Some((inner_ty, exp_mut)) => {
130 if *mutability != exp_mut {
131 // FIXME: emit type error?
132 }
133 inner_ty
134 }
135 _ => &Ty::Unknown,
136 };
137 let subty = self.infer_pat(*pat, expectation, default_bm);
138 Ty::apply_one(TypeCtor::Ref(*mutability), subty)
139 }
140 Pat::TupleStruct { path: p, args: subpats } => {
141 self.infer_tuple_struct_pat(p.as_ref(), subpats, expected, default_bm)
142 }
143 Pat::Record { path: p, args: fields } => {
144 self.infer_record_pat(p.as_ref(), fields, expected, default_bm, pat)
145 }
146 Pat::Path(path) => {
147 // FIXME use correct resolver for the surrounding expression
148 let resolver = self.resolver.clone();
149 self.infer_path(&resolver, &path, pat.into()).unwrap_or(Ty::Unknown)
150 }
151 Pat::Bind { mode, name: _, subpat } => {
152 let mode = if mode == &BindingAnnotation::Unannotated {
153 default_bm
154 } else {
155 BindingMode::convert(*mode)
156 };
157 let inner_ty = if let Some(subpat) = subpat {
158 self.infer_pat(*subpat, expected, default_bm)
159 } else {
160 expected.clone()
161 };
162 let inner_ty = self.insert_type_vars_shallow(inner_ty);
163
164 let bound_ty = match mode {
165 BindingMode::Ref(mutability) => {
166 Ty::apply_one(TypeCtor::Ref(mutability), inner_ty.clone())
167 }
168 BindingMode::Move => inner_ty.clone(),
169 };
170 let bound_ty = self.resolve_ty_as_possible(&mut vec![], bound_ty);
171 self.write_pat_ty(pat, bound_ty);
172 return inner_ty;
173 }
174 _ => Ty::Unknown,
175 };
176 // use a new type variable if we got Ty::Unknown here
177 let ty = self.insert_type_vars_shallow(ty);
178 self.unify(&ty, expected);
179 let ty = self.resolve_ty_as_possible(&mut vec![], ty);
180 self.write_pat_ty(pat, ty.clone());
181 ty
182 }
183}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-03 23:32:27 +0000