Add chalk_ir::Const to TyKind::Array

3 files changed, 16 insertions, 10 deletions

diff --git a/crates/hir_ty/src/infer/expr.rs b/crates/hir_ty/src/infer/expr.rs
index 796487d02..53d94fd0d 100644
--- a/crates/hir_ty/src/infer/expr.rs
+++ b/crates/hir_ty/src/infer/expr.rs
@@ -15,7 +15,7 @@ use stdx::always;
 use syntax::ast::RangeOp;
 
 use crate::{
-    autoderef,
+    autoderef, dummy_usize_const,
     lower::lower_to_chalk_mutability,
     method_resolution, op,
     primitive::{self, UintTy},
@@ -702,7 +702,7 @@ impl<'a> InferenceContext<'a> {
             }
             Expr::Array(array) => {
                 let elem_ty = match expected.ty.kind(&Interner) {
-                    TyKind::Array(st) | TyKind::Slice(st) => st.clone(),
+                    TyKind::Array(st, _) | TyKind::Slice(st) => st.clone(),
                     _ => self.table.new_type_var(),
                 };
 
@@ -726,7 +726,7 @@ impl<'a> InferenceContext<'a> {
                     }
                 }
 
-                TyKind::Array(elem_ty).intern(&Interner)
+                TyKind::Array(elem_ty, dummy_usize_const()).intern(&Interner)
             }
             Expr::Literal(lit) => match lit {
                 Literal::Bool(..) => TyKind::Scalar(Scalar::Bool).intern(&Interner),
@@ -736,7 +736,8 @@ impl<'a> InferenceContext<'a> {
                 }
                 Literal::ByteString(..) => {
                     let byte_type = TyKind::Scalar(Scalar::Uint(UintTy::U8)).intern(&Interner);
-                    let array_type = TyKind::Array(byte_type).intern(&Interner);
+                    let array_type =
+                        TyKind::Array(byte_type, dummy_usize_const()).intern(&Interner);
                     TyKind::Ref(Mutability::Not, static_lifetime(), array_type).intern(&Interner)
                 }
                 Literal::Char(..) => TyKind::Scalar(Scalar::Char).intern(&Interner),
diff --git a/crates/hir_ty/src/infer/pat.rs b/crates/hir_ty/src/infer/pat.rs
index 2848a393c..c1d7a6b76 100644
--- a/crates/hir_ty/src/infer/pat.rs
+++ b/crates/hir_ty/src/infer/pat.rs
@@ -214,17 +214,20 @@ impl<'a> InferenceContext<'a> {
                 return inner_ty;
             }
             Pat::Slice { prefix, slice, suffix } => {
-                let (container_ty, elem_ty): (fn(_) -> _, _) = match expected.kind(&Interner) {
-                    TyKind::Array(st) => (TyKind::Array, st.clone()),
-                    TyKind::Slice(st) => (TyKind::Slice, st.clone()),
-                    _ => (TyKind::Slice, self.err_ty()),
+                let elem_ty = match expected.kind(&Interner) {
+                    TyKind::Array(st, _) | TyKind::Slice(st) => st.clone(),
+                    _ => self.err_ty(),
                 };
 
                 for pat_id in prefix.iter().chain(suffix) {
                     self.infer_pat(*pat_id, &elem_ty, default_bm);
                 }
 
-                let pat_ty = container_ty(elem_ty).intern(&Interner);
+                let pat_ty = match expected.kind(&Interner) {
+                    TyKind::Array(_, const_) => TyKind::Array(elem_ty, const_.clone()),
+                    _ => TyKind::Slice(elem_ty),
+                }
+                .intern(&Interner);
                 if let Some(slice_pat_id) = slice {
                     self.infer_pat(*slice_pat_id, &pat_ty, default_bm);
                 }
diff --git a/crates/hir_ty/src/infer/unify.rs b/crates/hir_ty/src/infer/unify.rs
index c7878ebfd..7d76cda68 100644
--- a/crates/hir_ty/src/infer/unify.rs
+++ b/crates/hir_ty/src/infer/unify.rs
@@ -317,9 +317,11 @@ impl InferenceTable {
                 | (TyKind::Closure(.., substs1), TyKind::Closure(.., substs2)) => {
                     self.unify_substs(substs1, substs2, depth + 1)
                 }
+                (TyKind::Array(ty1, c1), TyKind::Array(ty2, c2)) if c1 == c2 => {
+                    self.unify_inner(ty1, ty2, depth + 1)
+                }
                 (TyKind::Ref(_, _, ty1), TyKind::Ref(_, _, ty2))
                 | (TyKind::Raw(_, ty1), TyKind::Raw(_, ty2))
-                | (TyKind::Array(ty1), TyKind::Array(ty2))
                 | (TyKind::Slice(ty1), TyKind::Slice(ty2)) => self.unify_inner(ty1, ty2, depth + 1),
                 _ => true, /* we checked equals_ctor already */
             }