Auto merge of #49861 - pnkfelix:compare-mode-nll-followup-2, r=nikoma…

…tsakis

Blindly checkpoint status of NLL mode ui tests

This takes the next (and potentially final?) step with #48879.

Namely, this PR got things to the point where I can successfully run `compiletest` on `src/test/ui` with `--compile-mode=nll`.

Here are the main pieces of it:

 1. To figure out how to even run `compiletest` normally on the ui directory, I ran `x.py test -vv`, and then looked for the `compiletest` invocation that mentioned `src/test/ui`.
 2. I took the aforementioned `compiletest` invocation and used it, adding `--compile-mode=nll` to the end. It had 170 failing cases.
 3. Due to #49855, I had to edit some of the tests so that they fail even under NLL, via `#[rustc_error]`. That's the first commit. (Then goto 2 to double-check no such tests remain.)
 4. I took the generated `build/target/test/foo.stderr` file for every case that failed, and blindly copied it to `src/test/foo.nll.stderr`. That's the second commit.
 5. Goto 2 until there were no failing cases.
 6. Remove any stamp files, and re-run `x.py test` to make sure that the edits and new `.nll.stderr` files haven't broken the pre-existing test suite.

src/test/ui/augmented-assignments.nll.stderr

@@ -0,0 +1,26 @@
+error[E0505]: cannot move out of `x` because it is borrowed
+  --> $DIR/augmented-assignments.rs:26:5
+   |
+LL |       x   //~ error: use of moved value: `x`
+   |       -
+   |       |
+   |  _____borrow of `x` occurs here
+   | |
+LL | |     //~^ value used here after move
+LL | |     +=
+LL | |     x;  //~ value moved here
+   | |     -
+   | |     |
+   | |_____move out of `x` occurs here
+   |       borrow later used here
+
+error[E0596]: cannot borrow immutable item `y` as mutable
+  --> $DIR/augmented-assignments.rs:30:5
+   |
+LL |     y   //~ error: cannot borrow immutable local variable `y` as mutable
+   |     ^ cannot borrow as mutable
+
+error: aborting due to 2 previous errors
+
+Some errors occurred: E0505, E0596.
+For more information about an error, try `rustc --explain E0505`.

src/test/ui/borrowck/borrowck-box-insensitivity.nll.stderr

@@ -0,0 +1,25 @@
+error[E0382]: use of moved value: `a.y`
+  --> $DIR/borrowck-box-insensitivity.rs:46:14
+   |
+LL |     let _x = a.x;
+   |              --- value moved here
+LL |     //~^ value moved here
+LL |     let _y = a.y; //~ ERROR use of moved
+   |              ^^^ value used here after move
+   |
+   = note: move occurs because `a.y` has type `std::boxed::Box<isize>`, which does not implement the `Copy` trait
+
+error[E0382]: use of moved value: `a.y`
+  --> $DIR/borrowck-box-insensitivity.rs:108:14
+   |
+LL |     let _x = a.x.x;
+   |              ----- value moved here
+LL |     //~^ value moved here
+LL |     let _y = a.y; //~ ERROR use of collaterally moved
+   |              ^^^ value used here after move
+   |
+   = note: move occurs because `a.y` has type `std::boxed::Box<isize>`, which does not implement the `Copy` trait
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0382`.

src/test/ui/borrowck/borrowck-closures-two-mut.nll.stderr

@@ -0,0 +1,78 @@
+error[E0499]: cannot borrow `x` as mutable more than once at a time (Ast)
+  --> $DIR/borrowck-closures-two-mut.rs:24:24
+   |
+LL |     let c1 = to_fn_mut(|| x = 4);
+   |                        -- - previous borrow occurs due to use of `x` in closure
+   |                        |
+   |                        first mutable borrow occurs here
+LL |     let c2 = to_fn_mut(|| x = 5); //~ ERROR cannot borrow `x` as mutable more than once
+   |                        ^^ - borrow occurs due to use of `x` in closure
+   |                        |
+   |                        second mutable borrow occurs here
+LL |     //~| ERROR cannot borrow `x` as mutable more than once
+LL | }
+   | - first borrow ends here
+
+error[E0499]: cannot borrow `x` as mutable more than once at a time (Ast)
+  --> $DIR/borrowck-closures-two-mut.rs:35:24
+   |
+LL |     let c1 = to_fn_mut(|| set(&mut x));
+   |                        --          - previous borrow occurs due to use of `x` in closure
+   |                        |
+   |                        first mutable borrow occurs here
+LL |     let c2 = to_fn_mut(|| set(&mut x)); //~ ERROR cannot borrow `x` as mutable more than once
+   |                        ^^          - borrow occurs due to use of `x` in closure
+   |                        |
+   |                        second mutable borrow occurs here
+LL |     //~| ERROR cannot borrow `x` as mutable more than once
+LL | }
+   | - first borrow ends here
+
+error[E0499]: cannot borrow `x` as mutable more than once at a time (Ast)
+  --> $DIR/borrowck-closures-two-mut.rs:42:24
+   |
+LL |     let c1 = to_fn_mut(|| x = 5);
+   |                        -- - previous borrow occurs due to use of `x` in closure
+   |                        |
+   |                        first mutable borrow occurs here
+LL |     let c2 = to_fn_mut(|| set(&mut x)); //~ ERROR cannot borrow `x` as mutable more than once
+   |                        ^^          - borrow occurs due to use of `x` in closure
+   |                        |
+   |                        second mutable borrow occurs here
+LL |     //~| ERROR cannot borrow `x` as mutable more than once
+LL | }
+   | - first borrow ends here
+
+error[E0499]: cannot borrow `x` as mutable more than once at a time (Ast)
+  --> $DIR/borrowck-closures-two-mut.rs:49:24
+   |
+LL |     let c1 = to_fn_mut(|| x = 5);
+   |                        -- - previous borrow occurs due to use of `x` in closure
+   |                        |
+   |                        first mutable borrow occurs here
+LL |     let c2 = to_fn_mut(|| { let _y = to_fn_mut(|| set(&mut x)); }); // (nested closure)
+   |                        ^^                                  - borrow occurs due to use of `x` in closure
+   |                        |
+   |                        second mutable borrow occurs here
+...
+LL | }
+   | - first borrow ends here
+
+error[E0499]: cannot borrow `x` as mutable more than once at a time (Ast)
+  --> $DIR/borrowck-closures-two-mut.rs:61:24
+   |
+LL |     let c1 = to_fn_mut(|| set(&mut *x.f));
+   |                        --           - previous borrow occurs due to use of `x` in closure
+   |                        |
+   |                        first mutable borrow occurs here
+LL |     let c2 = to_fn_mut(|| set(&mut *x.f));
+   |                        ^^           - borrow occurs due to use of `x` in closure
+   |                        |
+   |                        second mutable borrow occurs here
+...
+LL | }
+   | - first borrow ends here
+
+error: aborting due to 5 previous errors
+
+For more information about this error, try `rustc --explain E0499`.

src/test/ui/borrowck/borrowck-escaping-closure-error-1.nll.stderr

@@ -0,0 +1,14 @@
+error[E0597]: `books` does not live long enough
+  --> $DIR/borrowck-escaping-closure-error-1.rs:23:11
+   |
+LL |     spawn(|| books.push(4));
+   |           ^^^^^^^^^^^^^^^^ borrowed value does not live long enough
+LL |     //~^ ERROR E0373
+LL | }
+   | - borrowed value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0597`.

src/test/ui/borrowck/borrowck-escaping-closure-error-2.nll.stderr

@@ -0,0 +1,18 @@
+error[E0597]: `books` does not live long enough
+  --> $DIR/borrowck-escaping-closure-error-2.rs:21:14
+   |
+LL |     Box::new(|| books.push(4))
+   |              ^^^^^^^^^^^^^^^^ borrowed value does not live long enough
+LL |     //~^ ERROR E0373
+LL | }
+   | - borrowed value only lives until here
+   |
+note: borrowed value must be valid for the lifetime 'a as defined on the function body at 19:1...
+  --> $DIR/borrowck-escaping-closure-error-2.rs:19:1
+   |
+LL | fn foo<'a>(x: &'a i32) -> Box<FnMut()+'a> {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0597`.

src/test/ui/borrowck/borrowck-in-static.nll.stderr

@@ -0,0 +1,9 @@
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-in-static.rs:15:17
+   |
+LL |     Box::new(|| x) //~ ERROR cannot move out of captured outer variable
+   |                 ^ cannot move out of borrowed content
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0507`.

src/test/ui/borrowck/borrowck-move-error-with-note.nll.stderr

@@ -0,0 +1,40 @@
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-move-error-with-note.rs:23:19
+   |
+LL |         Foo::Foo1(num1,
+   |                   ^^^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-move-error-with-note.rs:24:19
+   |
+LL |                   num2) => (),
+   |                   ^^^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-move-error-with-note.rs:25:19
+   |
+LL |         Foo::Foo2(num) => (),
+   |                   ^^^ cannot move out of borrowed content
+
+error[E0509]: cannot move out of type `S`, which implements the `Drop` trait
+  --> $DIR/borrowck-move-error-with-note.rs:42:16
+   |
+LL |             f: _s,
+   |                ^^ cannot move out of here
+
+error[E0509]: cannot move out of type `S`, which implements the `Drop` trait
+  --> $DIR/borrowck-move-error-with-note.rs:43:16
+   |
+LL |             g: _t
+   |                ^^ cannot move out of here
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-move-error-with-note.rs:59:9
+   |
+LL |         n => {
+   |         ^ cannot move out of borrowed content
+
+error: aborting due to 6 previous errors
+
+Some errors occurred: E0507, E0509.
+For more information about an error, try `rustc --explain E0507`.

src/test/ui/borrowck/borrowck-move-out-of-vec-tail.nll.stderr

@@ -0,0 +1,15 @@
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-move-out-of-vec-tail.rs:30:33
+   |
+LL |                 &[Foo { string: a },
+   |                                 ^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-move-out-of-vec-tail.rs:34:33
+   |
+LL |                   Foo { string: b }] => {
+   |                                 ^ cannot move out of borrowed content
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0507`.

src/test/ui/borrowck/borrowck-report-with-custom-diagnostic.nll.stderr

@@ -0,0 +1,14 @@
+error: compilation successful
+  --> $DIR/borrowck-report-with-custom-diagnostic.rs:12:1
+   |
+LL | / fn main() { #![rustc_error] // rust-lang/rust#49855
+LL | |     // Original borrow ends at end of function
+LL | |     let mut x = 1;
+LL | |     let y = &mut x;
+...  |
+LL | |     //~^ immutable borrow occurs here
+LL | | }
+   | |_^
+
+error: aborting due to previous error
+

src/test/ui/borrowck/borrowck-report-with-custom-diagnostic.rs

@@ -7,9 +7,9 @@
 // <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.
-
+#![feature(rustc_attrs)]
 #![allow(dead_code)]
-fn main() {
+fn main() { #![rustc_error] // rust-lang/rust#49855
     // Original borrow ends at end of function
     let mut x = 1;
     let y = &mut x;

src/test/ui/borrowck/borrowck-vec-pattern-nesting.nll.stderr

@@ -0,0 +1,51 @@
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:42:15
+   |
+LL |         &mut [_a, //~ ERROR cannot move out
+   |               ^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:55:13
+   |
+LL |     let a = vec[0]; //~ ERROR cannot move out
+   |             ^^^^^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:65:10
+   |
+LL |          _b] => {}
+   |          ^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:68:13
+   |
+LL |     let a = vec[0]; //~ ERROR cannot move out
+   |             ^^^^^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:76:15
+   |
+LL |         &mut [_a, _b, _c] => {}  //~ ERROR cannot move out
+   |               ^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:76:19
+   |
+LL |         &mut [_a, _b, _c] => {}  //~ ERROR cannot move out
+   |                   ^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:76:23
+   |
+LL |         &mut [_a, _b, _c] => {}  //~ ERROR cannot move out
+   |                       ^^ cannot move out of borrowed content
+
+error[E0507]: cannot move out of borrowed content
+  --> $DIR/borrowck-vec-pattern-nesting.rs:80:13
+   |
+LL |     let a = vec[0]; //~ ERROR cannot move out
+   |             ^^^^^^ cannot move out of borrowed content
+
+error: aborting due to 8 previous errors
+
+For more information about this error, try `rustc --explain E0507`.

src/test/ui/borrowck/issue-45983.nll.stderr

@@ -0,0 +1,30 @@
+warning: not reporting region error due to -Znll
+  --> $DIR/issue-45983.rs:17:27
+   |
+LL |     give_any(|y| x = Some(y));
+   |                           ^
+
+error: free region `` does not outlive free region `'_#2r`
+  --> $DIR/issue-45983.rs:17:27
+   |
+LL |     give_any(|y| x = Some(y));
+   |                           ^
+
+error[E0594]: cannot assign to immutable item `x`
+  --> $DIR/issue-45983.rs:17:18
+   |
+LL |     give_any(|y| x = Some(y));
+   |                  ^^^^^^^^^^^ cannot mutate
+   |
+   = note: Value not mutable causing this error: `x`
+
+error[E0596]: cannot borrow immutable item `x` as mutable
+  --> $DIR/issue-45983.rs:17:14
+   |
+LL |     give_any(|y| x = Some(y));
+   |              ^^^^^^^^^^^^^^^ cannot borrow as mutable
+
+error: aborting due to 3 previous errors
+
+Some errors occurred: E0594, E0596.
+For more information about an error, try `rustc --explain E0594`.

src/test/ui/borrowck/issue-7573.nll.stderr

@@ -0,0 +1,14 @@
+warning: not reporting region error due to -Znll
+  --> $DIR/issue-7573.rs:27:31
+   |
+LL |     let mut lines_to_use: Vec<&CrateId> = Vec::new();
+   |                               ^
+
+error: free region `` does not outlive free region `'_#2r`
+  --> $DIR/issue-7573.rs:32:9
+   |
+LL |         lines_to_use.push(installed_id);
+   |         ^^^^^^^^^^^^
+
+error: aborting due to previous error
+

src/test/ui/borrowck/mut-borrow-in-loop.nll.stderr

@@ -0,0 +1,21 @@
+error[E0499]: cannot borrow `*arg` as mutable more than once at a time
+  --> $DIR/mut-borrow-in-loop.rs:20:25
+   |
+LL |             (self.func)(arg) //~ ERROR cannot borrow
+   |                         ^^^ mutable borrow starts here in previous iteration of loop
+
+error[E0499]: cannot borrow `*arg` as mutable more than once at a time
+  --> $DIR/mut-borrow-in-loop.rs:26:25
+   |
+LL |             (self.func)(arg) //~ ERROR cannot borrow
+   |                         ^^^ mutable borrow starts here in previous iteration of loop
+
+error[E0499]: cannot borrow `*arg` as mutable more than once at a time
+  --> $DIR/mut-borrow-in-loop.rs:33:25
+   |
+LL |             (self.func)(arg) //~ ERROR cannot borrow
+   |                         ^^^ mutable borrow starts here in previous iteration of loop
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0499`.

src/test/ui/borrowck/mut-borrow-outside-loop.nll.stderr

@@ -0,0 +1,14 @@
+error: compilation successful
+  --> $DIR/mut-borrow-outside-loop.rs:13:1
+   |
+LL | / fn main() { #![rustc_error] // rust-lang/rust#49855
+LL | |     let mut void = ();
+LL | |
+LL | |     let first = &mut void;
+...  |
+LL | |     }
+LL | | }
+   | |_^
+
+error: aborting due to previous error
+