Updated the most glaring instances of weak tests w.r.t. NLL that came…

… from rust-lang#53196.

See also the bulletpoint list on rust-lang#53351.

src/test/ui/borrowck/borrow-tuple-fields.nll.stderr

@@ -0,0 +1,65 @@
+error[E0505]: cannot move out of `x` because it is borrowed
+  --> $DIR/borrow-tuple-fields.rs:22:13
+   |
+LL |     let r = &x.0;
+   |             ---- borrow of `x.0` occurs here
+LL |     let y = x; //~ ERROR cannot move out of `x` because it is borrowed
+   |             ^ move out of `x` occurs here
+LL | 
+LL |     r.use_ref();
+   |     - borrow later used here
+
+error[E0502]: cannot borrow `x.0` as mutable because it is also borrowed as immutable
+  --> $DIR/borrow-tuple-fields.rs:28:13
+   |
+LL |     let a = &x.0;
+   |             ---- immutable borrow occurs here
+LL |     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable because it is also borrowed as
+   |             ^^^^^^^^ mutable borrow occurs here
+LL |     a.use_ref();
+   |     - borrow later used here
+
+error[E0499]: cannot borrow `x.0` as mutable more than once at a time
+  --> $DIR/borrow-tuple-fields.rs:33:13
+   |
+LL |     let a = &mut x.0;
+   |             -------- first mutable borrow occurs here
+LL |     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
+   |             ^^^^^^^^ second mutable borrow occurs here
+LL |     a.use_ref();
+   |     - borrow later used here
+
+error[E0505]: cannot move out of `x` because it is borrowed
+  --> $DIR/borrow-tuple-fields.rs:38:13
+   |
+LL |     let r = &x.0;
+   |             ---- borrow of `x.0` occurs here
+LL |     let y = x; //~ ERROR cannot move out of `x` because it is borrowed
+   |             ^ move out of `x` occurs here
+LL |     r.use_ref();
+   |     - borrow later used here
+
+error[E0502]: cannot borrow `x.0` as mutable because it is also borrowed as immutable
+  --> $DIR/borrow-tuple-fields.rs:43:13
+   |
+LL |     let a = &x.0;
+   |             ---- immutable borrow occurs here
+LL |     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable because it is also borrowed as
+   |             ^^^^^^^^ mutable borrow occurs here
+LL |     a.use_ref();
+   |     - borrow later used here
+
+error[E0499]: cannot borrow `x.0` as mutable more than once at a time
+  --> $DIR/borrow-tuple-fields.rs:48:13
+   |
+LL |     let a = &mut x.0;
+   |             -------- first mutable borrow occurs here
+LL |     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
+   |             ^^^^^^^^ second mutable borrow occurs here
+LL |     a.use_mut();
+   |     - borrow later used here
+
+error: aborting due to 6 previous errors
+
+Some errors occurred: E0499, E0502, E0505.
+For more information about an error, try `rustc --explain E0499`.

src/test/ui/borrowck/borrow-tuple-fields.rs

@@ -8,10 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// ignore-compare-mode-nll
-
 #![feature(box_syntax)]
 
+
+
 struct Foo(Box<isize>, isize);
 
 struct Bar(isize, isize);
@@ -21,24 +21,33 @@ fn main() {
     let r = &x.0;
     let y = x; //~ ERROR cannot move out of `x` because it is borrowed
 
+    r.use_ref();
+
     let mut x = (1, 2);
     let a = &x.0;
     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable because it is also borrowed as
+    a.use_ref();
 
     let mut x = (1, 2);
     let a = &mut x.0;
     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
-
+    a.use_ref();
 
     let x = Foo(box 1, 2);
     let r = &x.0;
     let y = x; //~ ERROR cannot move out of `x` because it is borrowed
+    r.use_ref();
 
     let mut x = Bar(1, 2);
     let a = &x.0;
     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable because it is also borrowed as
+    a.use_ref();
 
     let mut x = Bar(1, 2);
     let a = &mut x.0;
     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
+    a.use_mut();
 }
+
+trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { }  }
+impl<T> Fake for T { }

src/test/ui/borrowck/borrow-tuple-fields.stderr

@@ -7,7 +7,7 @@ LL |     let y = x; //~ ERROR cannot move out of `x` because it is borrowed
    |         ^ move out of `x` occurs here
 
 error[E0502]: cannot borrow `x.0` as mutable because it is also borrowed as immutable
-  --> $DIR/borrow-tuple-fields.rs:26:18
+  --> $DIR/borrow-tuple-fields.rs:28:18
    |
 LL |     let a = &x.0;
    |              --- immutable borrow occurs here
@@ -18,7 +18,7 @@ LL | }
    | - immutable borrow ends here
 
 error[E0499]: cannot borrow `x.0` as mutable more than once at a time
-  --> $DIR/borrow-tuple-fields.rs:30:18
+  --> $DIR/borrow-tuple-fields.rs:33:18
    |
 LL |     let a = &mut x.0;
    |                  --- first mutable borrow occurs here
@@ -29,15 +29,15 @@ LL | }
    | - first borrow ends here
 
 error[E0505]: cannot move out of `x` because it is borrowed
-  --> $DIR/borrow-tuple-fields.rs:35:9
+  --> $DIR/borrow-tuple-fields.rs:38:9
    |
 LL |     let r = &x.0;
    |              --- borrow of `x.0` occurs here
 LL |     let y = x; //~ ERROR cannot move out of `x` because it is borrowed
    |         ^ move out of `x` occurs here
 
 error[E0502]: cannot borrow `x.0` as mutable because it is also borrowed as immutable
-  --> $DIR/borrow-tuple-fields.rs:39:18
+  --> $DIR/borrow-tuple-fields.rs:43:18
    |
 LL |     let a = &x.0;
    |              --- immutable borrow occurs here
@@ -48,12 +48,13 @@ LL | }
    | - immutable borrow ends here
 
 error[E0499]: cannot borrow `x.0` as mutable more than once at a time
-  --> $DIR/borrow-tuple-fields.rs:43:18
+  --> $DIR/borrow-tuple-fields.rs:48:18
    |
 LL |     let a = &mut x.0;
    |                  --- first mutable borrow occurs here
 LL |     let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
    |                  ^^^ second mutable borrow occurs here
+LL |     a.use_mut();
 LL | }
    | - first borrow ends here
 

src/test/ui/borrowck/borrowck-borrow-mut-object-twice.nll.stderr

@@ -0,0 +1,13 @@
+error[E0499]: cannot borrow `*x` as mutable more than once at a time
+  --> $DIR/borrowck-borrow-mut-object-twice.rs:23:5
+   |
+LL |     let y = x.f1();
+   |             - first mutable borrow occurs here
+LL |     x.f2(); //~ ERROR cannot borrow `*x` as mutable
+   |     ^ second mutable borrow occurs here
+LL |     y.use_ref();
+   |     - borrow later used here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0499`.

src/test/ui/borrowck/borrowck-borrow-mut-object-twice.rs

@@ -8,19 +8,23 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// ignore-compare-mode-nll
-
 // Check that `&mut` objects cannot be borrowed twice, just like
 // other `&mut` pointers.
 
+
+
 trait Foo {
     fn f1(&mut self) -> &();
     fn f2(&mut self);
 }
 
 fn test(x: &mut Foo) {
-    let _y = x.f1();
+    let y = x.f1();
     x.f2(); //~ ERROR cannot borrow `*x` as mutable
+    y.use_ref();
 }
 
 fn main() {}
+
+trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { }  }
+impl<T> Fake for T { }

src/test/ui/borrowck/borrowck-borrow-mut-object-twice.stderr

@@ -1,10 +1,11 @@
 error[E0499]: cannot borrow `*x` as mutable more than once at a time
   --> $DIR/borrowck-borrow-mut-object-twice.rs:23:5
    |
-LL |     let _y = x.f1();
-   |              - first mutable borrow occurs here
+LL |     let y = x.f1();
+   |             - first mutable borrow occurs here
 LL |     x.f2(); //~ ERROR cannot borrow `*x` as mutable
    |     ^ second mutable borrow occurs here
+LL |     y.use_ref();
 LL | }
    | - first borrow ends here
 

src/test/ui/borrowck/borrowck-closures-unique-imm.nll.stderr

@@ -0,0 +1,13 @@
+error[E0502]: cannot borrow `this.x` as mutable because it is also borrowed as immutable
+  --> $DIR/borrowck-closures-unique-imm.rs:23:9
+   |
+LL |         let p = &this.x;
+   |                 ------- immutable borrow occurs here
+LL |         &mut this.x; //~ ERROR cannot borrow
+   |         ^^^^^^^^^^^ mutable borrow occurs here
+LL |         p.use_ref();
+   |         - borrow later used here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0502`.

src/test/ui/borrowck/borrowck-closures-unique-imm.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// ignore-compare-mode-nll
+
 
 struct Foo {
     x: isize,
@@ -21,6 +21,10 @@ pub fn main() {
     let mut r = || {
         let p = &this.x;
         &mut this.x; //~ ERROR cannot borrow
+        p.use_ref();
     };
     r()
 }
+
+trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { }  }
+impl<T> Fake for T { }

src/test/ui/borrowck/borrowck-closures-unique-imm.stderr

@@ -5,6 +5,7 @@ LL |         let p = &this.x;
    |                  ------ immutable borrow occurs here
 LL |         &mut this.x; //~ ERROR cannot borrow
    |              ^^^^^^ mutable borrow occurs here
+LL |         p.use_ref();
 LL |     };
    |     - immutable borrow ends here
 

src/test/ui/borrowck/borrowck-issue-2657-1.nll.stderr

@@ -0,0 +1,13 @@
+error[E0505]: cannot move out of `x` because it is borrowed
+  --> $DIR/borrowck-issue-2657-1.rs:19:18
+   |
+LL |       Some(ref _y) => {
+   |            ------ borrow of `x.0` occurs here
+LL |         let _a = x; //~ ERROR cannot move
+   |                  ^ move out of `x` occurs here
+LL |         _y.use_ref();
+   |         -- borrow later used here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0505`.

src/test/ui/borrowck/borrowck-issue-2657-1.rs

@@ -8,16 +8,20 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// ignore-compare-mode-nll
-
 #![feature(box_syntax)]
 
+
+
 fn main() {
     let x: Option<Box<_>> = Some(box 1);
     match x {
       Some(ref _y) => {
         let _a = x; //~ ERROR cannot move
+        _y.use_ref();
       }
       _ => {}
     }
 }
+
+trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { }  }
+impl<T> Fake for T { }

src/test/ui/borrowck/borrowck-loan-blocks-move-cc.nll.stderr

@@ -0,0 +1,29 @@
+error[E0505]: cannot move out of `v` because it is borrowed
+  --> $DIR/borrowck-loan-blocks-move-cc.rs:24:19
+   |
+LL |     let w = &v;
+   |             -- borrow of `v` occurs here
+LL |     thread::spawn(move|| {
+   |                   ^^^^^^ move out of `v` occurs here
+LL |         println!("v={}", *v);
+   |                           - move occurs due to use in closure
+...
+LL |     w.use_ref();
+   |     - borrow later used here
+
+error[E0505]: cannot move out of `v` because it is borrowed
+  --> $DIR/borrowck-loan-blocks-move-cc.rs:34:19
+   |
+LL |     let w = &v;
+   |             -- borrow of `v` occurs here
+LL |     thread::spawn(move|| {
+   |                   ^^^^^^ move out of `v` occurs here
+LL |         println!("v={}", *v);
+   |                           - move occurs due to use in closure
+...
+LL |     w.use_ref();
+   |     - borrow later used here
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0505`.

src/test/ui/borrowck/borrowck-loan-blocks-move-cc.rs

@@ -8,33 +8,38 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// ignore-compare-mode-nll
-
 #![feature(box_syntax)]
 
 use std::thread;
 
+
+
 fn borrow<F>(v: &isize, f: F) where F: FnOnce(&isize) {
     f(v);
 }
 
 fn box_imm() {
     let v: Box<_> = box 3;
-    let _w = &v;
+    let w = &v;
     thread::spawn(move|| {
         println!("v={}", *v);
         //~^ ERROR cannot move `v` into closure
     });
+    w.use_ref();
 }
 
 fn box_imm_explicit() {
     let v: Box<_> = box 3;
-    let _w = &v;
+    let w = &v;
     thread::spawn(move|| {
         println!("v={}", *v);
         //~^ ERROR cannot move
     });
+    w.use_ref();
 }
 
 fn main() {
 }
+
+trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { }  }
+impl<T> Fake for T { }

src/test/ui/borrowck/borrowck-loan-blocks-move-cc.stderr

@@ -1,17 +1,17 @@
 error[E0504]: cannot move `v` into closure because it is borrowed
   --> $DIR/borrowck-loan-blocks-move-cc.rs:25:27
    |
-LL |     let _w = &v;
-   |               - borrow of `v` occurs here
+LL |     let w = &v;
+   |              - borrow of `v` occurs here
 LL |     thread::spawn(move|| {
 LL |         println!("v={}", *v);
    |                           ^ move into closure occurs here
 
 error[E0504]: cannot move `v` into closure because it is borrowed
-  --> $DIR/borrowck-loan-blocks-move-cc.rs:34:27
+  --> $DIR/borrowck-loan-blocks-move-cc.rs:35:27
    |
-LL |     let _w = &v;
-   |               - borrow of `v` occurs here
+LL |     let w = &v;
+   |              - borrow of `v` occurs here
 LL |     thread::spawn(move|| {
 LL |         println!("v={}", *v);
    |                           ^ move into closure occurs here