Demonstrate next-solver missing diagnostic

Author: oli-obk

tests/ui/moves/assignment-of-clone-call-on-ref-due-to-missing-bound.fixed renamed to tests/ui/moves/assignment-of-clone-call-on-ref-due-to-missing-bound.current.fixed

@@ -1,16 +1,17 @@
-//@ run-rustfix
+//@[current] run-rustfix
+//@ revisions: current next
+//@[next] compile-flags: -Znext-solver
 #![allow(unused_variables, dead_code)]
-use std::collections::BTreeMap;
-use std::collections::HashSet;
+use std::collections::{BTreeMap, HashSet};
 
-#[derive(Debug,Eq,PartialEq,Hash)]
+#[derive(Debug, Eq, PartialEq, Hash)]
 #[derive(Clone)]
 enum Day {
     Mon,
 }
 
 struct Class {
-    days: BTreeMap<u32, HashSet<Day>>
+    days: BTreeMap<u32, HashSet<Day>>,
 }
 
 impl Class {

tests/ui/moves/assignment-of-clone-call-on-ref-due-to-missing-bound.stderr renamed to tests/ui/moves/assignment-of-clone-call-on-ref-due-to-missing-bound.current.stderr

@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:18:39
+  --> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:19:39
    |
 LL |             let mut x: HashSet<Day> = v.clone();
    |                        ------------   ^^^^^^^^^ expected `HashSet<Day>`, found `&HashSet<Day>`
@@ -9,7 +9,7 @@ LL |             let mut x: HashSet<Day> = v.clone();
    = note: expected struct `HashSet<_>`
            found reference `&HashSet<_>`
 note: `HashSet<Day>` does not implement `Clone`, so `&HashSet<Day>` was cloned instead
-  --> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:18:39
+  --> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:19:39
    |
 LL |             let mut x: HashSet<Day> = v.clone();
    |                                       ^

tests/ui/moves/assignment-of-clone-call-on-ref-due-to-missing-bound.next.stderr

@@ -0,0 +1,19 @@
+error[E0308]: mismatched types
+  --> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:19:39
+   |
+LL |             let mut x: HashSet<Day> = v.clone();
+   |                        ------------   ^^^^^^^^^ expected `HashSet<Day>`, found `&HashSet<Day>`
+   |                        |
+   |                        expected due to this
+   |
+   = note: expected struct `HashSet<_>`
+           found reference `&HashSet<_>`
+note: `HashSet<Day>` does not implement `Clone`, so `&HashSet<Day>` was cloned instead
+  --> $DIR/assignment-of-clone-call-on-ref-due-to-missing-bound.rs:19:39
+   |
+LL |             let mut x: HashSet<Day> = v.clone();
+   |                                       ^
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.

tests/ui/moves/assignment-of-clone-call-on-ref-due-to-missing-bound.rs

@@ -1,15 +1,16 @@
-//@ run-rustfix
+//@[current] run-rustfix
+//@ revisions: current next
+//@[next] compile-flags: -Znext-solver
 #![allow(unused_variables, dead_code)]
-use std::collections::BTreeMap;
-use std::collections::HashSet;
+use std::collections::{BTreeMap, HashSet};
 
-#[derive(Debug,Eq,PartialEq,Hash)]
+#[derive(Debug, Eq, PartialEq, Hash)]
 enum Day {
     Mon,
 }
 
 struct Class {
-    days: BTreeMap<u32, HashSet<Day>>
+    days: BTreeMap<u32, HashSet<Day>>,
 }
 
 impl Class {