Fix type of byte literals

They're `&[u8; N]`, not `&[u8]` (see #4374).

Author: flodiebold

crates/ra_hir_ty/src/infer/expr.rs

@@ -501,8 +501,8 @@ impl<'a> InferenceContext<'a> {
                 }
                 Literal::ByteString(..) => {
                     let byte_type = Ty::simple(TypeCtor::Int(Uncertain::Known(IntTy::u8())));
-                    let slice_type = Ty::apply_one(TypeCtor::Slice, byte_type);
-                    Ty::apply_one(TypeCtor::Ref(Mutability::Shared), slice_type)
+                    let array_type = Ty::apply_one(TypeCtor::Array, byte_type);
+                    Ty::apply_one(TypeCtor::Ref(Mutability::Shared), array_type)
                 }
                 Literal::Char(..) => Ty::simple(TypeCtor::Char),
                 Literal::Int(_v, ty) => Ty::simple(TypeCtor::Int((*ty).into())),

crates/ra_hir_ty/src/tests/method_resolution.rs

@@ -17,19 +17,20 @@ impl<T> [T] {
 #[lang = "slice_alloc"]
 impl<T> [T] {}
 
-fn test() {
-    <[_]>::foo(b"foo");
+fn test(x: &[u8]) {
+    <[_]>::foo(x);
 }
 "#),
         @r###"
     45..49 'self': &[T]
     56..79 '{     ...     }': T
     66..73 'loop {}': !
     71..73 '{}': ()
-    133..160 '{     ...o"); }': ()
-    139..149 '<[_]>::foo': fn foo<u8>(&[u8]) -> u8
-    139..157 '<[_]>:..."foo")': u8
-    150..156 'b"foo"': &[u8]
+    131..132 'x': &[u8]
+    141..163 '{     ...(x); }': ()
+    147..157 '<[_]>::foo': fn foo<u8>(&[u8]) -> u8
+    147..160 '<[_]>::foo(x)': u8
+    158..159 'x': &[u8]
     "###
     );
 }

crates/ra_hir_ty/src/tests/simple.rs

@@ -414,15 +414,15 @@ fn test() {
     27..31 '5f32': f32
     37..41 '5f64': f64
     47..54 '"hello"': &str
-    60..68 'b"bytes"': &[u8]
+    60..68 'b"bytes"': &[u8; _]
     74..77 ''c'': char
     83..87 'b'b'': u8
     93..97 '3.14': f64
     103..107 '5000': i32
     113..118 'false': bool
     124..128 'true': bool
     134..202 'r#"   ...    "#': &str
-    208..218 'br#"yolo"#': &[u8]
+    208..218 'br#"yolo"#': &[u8; _]
     "###
     );
 }