Move /src/test to /tests

tests/ui/array-slice-vec/vector-cast-weirdness.rs

@@ -0,0 +1,34 @@
+// Issue #14893. Tests that casts from vectors don't behave strangely in the
+// presence of the `_` type shorthand notation.
+//
+// Update: after a change to the way casts are done, we have more type information
+// around and so the errors here are no longer exactly the same.
+//
+// Update: With PR #81479 some of the previously rejected cases are now allowed.
+// New test cases added.
+
+struct X {
+    y: [u8; 2],
+}
+
+fn main() {
+    let x1 = X { y: [0, 0] };
+
+    // No longer a type mismatch - the `_` can be fully resolved by type inference.
+    let p1: *const u8 = &x1.y as *const _;
+    let p1: *mut u8 = &x1.y as *mut _;
+    //~^ ERROR: casting `&[u8; 2]` as `*mut u8` is invalid
+    let t1: *const [u8; 2] = &x1.y as *const _;
+    let t1: *mut [u8; 2] = &x1.y as *mut _;
+    //~^ ERROR: casting `&[u8; 2]` as `*mut [u8; 2]` is invalid
+    let h1: *const [u8; 2] = &x1.y as *const [u8; 2];
+    let t1: *mut [u8; 2] = &x1.y as *mut [u8; 2];
+    //~^ ERROR: casting `&[u8; 2]` as `*mut [u8; 2]` is invalid
+
+    let mut x1 = X { y: [0, 0] };
+
+    let p1: *mut u8 = &mut x1.y as *mut _;
+    let p2: *const u8 = &mut x1.y as *const _;
+    let t1: *mut [u8; 2] = &mut x1.y as *mut _;
+    let h1: *mut [u8; 2] = &mut x1.y as *mut [u8; 2];
+}