Reword reason for move note

src/librustc_borrowck/borrowck/mod.rs

@@ -346,6 +346,16 @@ impl<'tcx> LoanPath<'tcx> {
     }
 
     fn to_type(&self) -> Ty<'tcx> { self.ty }
+
+    fn is_downcast(&self) -> bool {
+        match self.kind {
+            LpDowncast(_, _) => true,
+            LpExtend(ref lp, _, LpInterior(_, _)) => {
+                lp.is_downcast()
+            }
+            _ => false,
+        }
+    }
 }
 
 // FIXME (pnkfelix): See discussion here
@@ -715,16 +725,20 @@ impl<'a, 'tcx> BorrowckCtxt<'a, 'tcx> {
                          move_note));
             err
         } else {
-            err.span_label(use_span, format!("value {} here after move", verb_participle))
-               .span_label(move_span, format!("value moved{} here", move_note));
+            err.span_label(use_span, format!("value {} here after move", verb_participle));
+            err.span_label(move_span, format!("value moved{} here", move_note));
             err
         };
 
         if need_note {
-            err.note(&format!("move occurs because `{}` has type `{}`, \
-                               which does not implement the `Copy` trait",
-                              self.loan_path_to_string(moved_lp),
-                              moved_lp.ty));
+            err.note(&format!(
+                "move occurs because {} has type `{}`, which does not implement the `Copy` trait",
+                if moved_lp.is_downcast() {
+                    "the value".to_string()
+                } else {
+                    format!("`{}`", self.loan_path_to_string(moved_lp))
+                },
+                moved_lp.ty));
         }
 
         // Note: we used to suggest adding a `ref binding` or calling
@@ -1391,7 +1405,7 @@ impl<'a, 'tcx> BorrowckCtxt<'a, 'tcx> {
             LpDowncast(ref lp_base, variant_def_id) => {
                 out.push('(');
                 self.append_autoderefd_loan_path_to_string(&lp_base, out);
-                out.push(':');
+                out.push_str(DOWNCAST_PRINTED_OPERATOR);
                 out.push_str(&self.tcx.item_path_str(variant_def_id));
                 out.push(')');
             }

src/test/compile-fail/issue-24357.rs

@@ -12,9 +12,9 @@ struct NoCopy;
 fn main() {
    let x = NoCopy;
    let f = move || { let y = x; };
-   //~^ value moved (into closure) here
+   //~^ NOTE value moved (into closure) here
    let z = x;
    //~^ ERROR use of moved value: `x`
-   //~| value used here after move
-   //~| move occurs because `x` has type `NoCopy`
+   //~| NOTE value used here after move
+   //~| NOTE move occurs because `x` has type `NoCopy`
 }

src/test/compile-fail/moves-based-on-type-distribute-copy-over-paren.rs

@@ -17,17 +17,19 @@ fn touch<A>(_a: &A) {}
 fn f00() {
     let x = "hi".to_string();
     let _y = Foo { f:x };
-    //~^ value moved here
+    //~^ NOTE value moved here
     touch(&x); //~ ERROR use of moved value: `x`
-    //~^ value used here after move
-    //~| move occurs because `x` has type `std::string::String`
+    //~^ NOTE value used here after move
+    //~| NOTE move occurs because `x` has type `std::string::String`
 }
 
 fn f05() {
     let x = "hi".to_string();
     let _y = Foo { f:(((x))) };
-    //~^ value moved here
+    //~^ NOTE value moved here
     touch(&x); //~ ERROR use of moved value: `x`
+    //~^ NOTE value used here after move
+    //~| NOTE move occurs because `x` has type `std::string::String`
 }
 
 fn f10() {

src/test/ui/borrowck/issue-41962.rs

@@ -0,0 +1,20 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub fn main(){
+    let maybe = Some(vec![true, true]);
+
+    loop {
+        if let Some(thing) = maybe {
+        //~^ ERROR use of partially moved value
+        //~| ERROR use of moved value
+        }
+    }
+}

src/test/ui/borrowck/issue-41962.stderr

@@ -0,0 +1,20 @@
+error[E0382]: use of partially moved value: `maybe`
+  --> $DIR/issue-41962.rs:15:30
+   |
+15 |         if let Some(thing) = maybe {
+   |                     -----    ^^^^^ value used here after move
+   |                     |
+   |                     value moved here
+   |
+   = note: move occurs because the value has type `std::vec::Vec<bool>`, which does not implement the `Copy` trait
+
+error[E0382]: use of moved value: `(maybe as std::prelude::v1::Some).0`
+  --> $DIR/issue-41962.rs:15:21
+   |
+15 |         if let Some(thing) = maybe {
+   |                     ^^^^^ value moved here in previous iteration of loop
+   |
+   = note: move occurs because the value has type `std::vec::Vec<bool>`, which does not implement the `Copy` trait
+
+error: aborting due to 2 previous errors
+