Harmonize use of leaf and root obligation in trait error reporting

compiler-errors · compiler-errors · commit c453c82de486 · 2024-06-12T20:57:23.000-04:00
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
diff --git a/tests/ui/auto-traits/typeck-default-trait-impl-precedence.stderr b/tests/ui/auto-traits/typeck-default-trait-impl-precedence.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `&'static u32: Defaulted` is not satisfied
   --> $DIR/typeck-default-trait-impl-precedence.rs:19:20
    |
 LL |     is_defaulted::<&'static u32>();
-   |                    ^^^^^^^^^^^^ the trait `Signed` is not implemented for `&'static u32`, which is required by `&'static u32: Defaulted`
+   |                    ^^^^^^^^^^^^ the trait `Signed` is not implemented for `u32`, which is required by `&'static u32: Defaulted`
    |
 note: required for `&'static u32` to implement `Defaulted`
   --> $DIR/typeck-default-trait-impl-precedence.rs:10:19
diff --git a/tests/ui/generic-associated-types/assume-gat-normalization-for-nested-goals.next.stderr b/tests/ui/generic-associated-types/assume-gat-normalization-for-nested-goals.next.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `i32: Baz<Self>` is not satisfied
   --> $DIR/assume-gat-normalization-for-nested-goals.rs:9:30
    |
 LL |     type Bar<T>: Baz<Self> = i32;
-   |                              ^^^ the trait `Eq<i32>` is not implemented for `i32`, which is required by `i32: Baz<Self>`
+   |                              ^^^ the trait `Eq<i32>` is not implemented for `<Self as Foo>::Bar<()>`, which is required by `i32: Baz<Self>`
    |
 note: required for `i32` to implement `Baz<Self>`
   --> $DIR/assume-gat-normalization-for-nested-goals.rs:16:23
diff --git a/tests/ui/kindck/kindck-send-object.stderr b/tests/ui/kindck/kindck-send-object.stderr
@@ -4,7 +4,7 @@ error[E0277]: `&'static (dyn Dummy + 'static)` cannot be sent between threads sa
 LL |     assert_send::<&'static (dyn Dummy + 'static)>();
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&'static (dyn Dummy + 'static)` cannot be sent between threads safely
    |
-   = help: the trait `Sync` is not implemented for `&'static (dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
+   = help: the trait `Sync` is not implemented for `(dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
    = note: required for `&'static (dyn Dummy + 'static)` to implement `Send`
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-object.rs:5:18
diff --git a/tests/ui/kindck/kindck-send-object1.stderr b/tests/ui/kindck/kindck-send-object1.stderr
@@ -4,7 +4,7 @@ error[E0277]: `&'a (dyn Dummy + 'a)` cannot be sent between threads safely
 LL |     assert_send::<&'a dyn Dummy>();
    |                   ^^^^^^^^^^^^^ `&'a (dyn Dummy + 'a)` cannot be sent between threads safely
    |
-   = help: the trait `Sync` is not implemented for `&'a (dyn Dummy + 'a)`, which is required by `&'a (dyn Dummy + 'a): Send`
+   = help: the trait `Sync` is not implemented for `(dyn Dummy + 'a)`, which is required by `&'a (dyn Dummy + 'a): Send`
    = note: required for `&'a (dyn Dummy + 'a)` to implement `Send`
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-object1.rs:5:18
diff --git a/tests/ui/kindck/kindck-send-object2.stderr b/tests/ui/kindck/kindck-send-object2.stderr
@@ -4,7 +4,7 @@ error[E0277]: `&'static (dyn Dummy + 'static)` cannot be sent between threads sa
 LL |     assert_send::<&'static dyn Dummy>();
    |                   ^^^^^^^^^^^^^^^^^^ `&'static (dyn Dummy + 'static)` cannot be sent between threads safely
    |
-   = help: the trait `Sync` is not implemented for `&'static (dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
+   = help: the trait `Sync` is not implemented for `(dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
    = note: required for `&'static (dyn Dummy + 'static)` to implement `Send`
 note: required by a bound in `assert_send`
   --> $DIR/kindck-send-object2.rs:3:18
diff --git a/tests/ui/suggestions/suggest-remove-refs-5.stderr b/tests/ui/suggestions/suggest-remove-refs-5.stderr
@@ -4,7 +4,7 @@ error[E0277]: `&mut &mut &mut &mut Vec<i32>` is not an iterator
 LL |     for _ in &mut &mut v {}
    |              ^^^^^^^^^^^ `&mut &mut &mut &mut Vec<i32>` is not an iterator
    |
-   = help: the trait `Iterator` is not implemented for `&mut &mut &mut &mut Vec<i32>`, which is required by `&mut &mut &mut &mut Vec<i32>: IntoIterator`
+   = help: the trait `Iterator` is not implemented for `Vec<i32>`, which is required by `&mut &mut &mut &mut Vec<i32>: IntoIterator`
    = note: required for `&mut Vec<i32>` to implement `Iterator`
    = note: 3 redundant requirements hidden
    = note: required for `&mut &mut &mut &mut Vec<i32>` to implement `Iterator`
@@ -21,7 +21,7 @@ error[E0277]: `&mut &mut &mut [u8; 1]` is not an iterator
 LL |     for _ in &mut v {}
    |              ^^^^^^ `&mut &mut &mut [u8; 1]` is not an iterator
    |
-   = help: the trait `Iterator` is not implemented for `&mut &mut &mut [u8; 1]`, which is required by `&mut &mut &mut [u8; 1]: IntoIterator`
+   = help: the trait `Iterator` is not implemented for `[u8; 1]`, which is required by `&mut &mut &mut [u8; 1]: IntoIterator`
    = note: required for `&mut [u8; 1]` to implement `Iterator`
    = note: 2 redundant requirements hidden
    = note: required for `&mut &mut &mut [u8; 1]` to implement `Iterator`
diff --git a/tests/ui/traits/next-solver/auto-with-drop_tracking_mir.fail.stderr b/tests/ui/traits/next-solver/auto-with-drop_tracking_mir.fail.stderr
@@ -4,7 +4,7 @@ error: future cannot be sent between threads safely
 LL |     is_send(foo());
    |             ^^^^^ future returned by `foo` is not `Send`
    |
-   = help: the trait `Sync` is not implemented for `impl Future<Output = ()>`, which is required by `impl Future<Output = ()>: Send`
+   = help: the trait `Sync` is not implemented for `NotSync`, which is required by `impl Future<Output = ()>: Send`
 note: future is not `Send` as this value is used across an await
   --> $DIR/auto-with-drop_tracking_mir.rs:16:11
    |
diff --git a/tests/ui/traits/next-solver/diagnostics/point-at-failing-nested.stderr b/tests/ui/traits/next-solver/diagnostics/point-at-failing-nested.stderr
@@ -4,6 +4,11 @@ error[E0277]: the trait bound `(): Foo` is not satisfied
 LL |     needs_foo::<()>();
    |                 ^^ the trait `Bar` is not implemented for `()`, which is required by `(): Foo`
    |
+help: this trait has no implementations, consider adding one
+  --> $DIR/point-at-failing-nested.rs:4:1
+   |
+LL | trait Bar {}
+   | ^^^^^^^^^
 note: required for `()` to implement `Foo`
   --> $DIR/point-at-failing-nested.rs:9:12
    |
diff --git a/tests/ui/traits/next-solver/diagnostics/where-clause-doesnt-apply.stderr b/tests/ui/traits/next-solver/diagnostics/where-clause-doesnt-apply.stderr
@@ -6,6 +6,11 @@ LL |     needs_foo(());
    |     |
    |     required by a bound introduced by this call
    |
+help: this trait has no implementations, consider adding one
+  --> $DIR/where-clause-doesnt-apply.rs:2:1
+   |
+LL | trait Bar {}
+   | ^^^^^^^^^
 note: required for `()` to implement `Foo`
   --> $DIR/where-clause-doesnt-apply.rs:4:9
    |
diff --git a/tests/ui/traits/suggest-dereferences/root-obligation.stderr b/tests/ui/traits/suggest-dereferences/root-obligation.stderr
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `&char: Pattern<'_>` is not satisfied
   --> $DIR/root-obligation.rs:6:38
    |
 LL |         .filter(|c| "aeiou".contains(c))
-   |                             -------- ^ the trait `Fn(char)` is not implemented for `&char`, which is required by `&char: Pattern<'_>`
+   |                             -------- ^ the trait `Fn(char)` is not implemented for `char`, which is required by `&char: Pattern<'_>`
    |                             |
    |                             required by a bound introduced by this call
    |
diff --git a/tests/ui/transmutability/references/unsafecell.stderr b/tests/ui/transmutability/references/unsafecell.stderr
@@ -2,7 +2,7 @@ error[E0277]: `&u8` cannot be safely transmuted into `&UnsafeCell<u8>`
   --> $DIR/unsafecell.rs:27:50
    |
 LL |     assert::is_maybe_transmutable::<&'static u8, &'static UnsafeCell<u8>>();
-   |                                                  ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Freeze` is not implemented for `&'static UnsafeCell<u8>`
+   |                                                  ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Freeze` is not implemented for `UnsafeCell<u8>`
    |
 note: required by a bound in `is_maybe_transmutable`
   --> $DIR/unsafecell.rs:12:14
@@ -17,7 +17,7 @@ error[E0277]: `&UnsafeCell<u8>` cannot be safely transmuted into `&UnsafeCell<u8
   --> $DIR/unsafecell.rs:29:62
    |
 LL |     assert::is_maybe_transmutable::<&'static UnsafeCell<u8>, &'static UnsafeCell<u8>>();
-   |                                                              ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Freeze` is not implemented for `&'static UnsafeCell<u8>`
+   |                                                              ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Freeze` is not implemented for `UnsafeCell<u8>`
    |
 note: required by a bound in `is_maybe_transmutable`
   --> $DIR/unsafecell.rs:12:14

Original file line number	Diff line number	Diff line change
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `&'static u32: Defaulted` is not satisfied
`2`	`2`	`--> $DIR/typeck-default-trait-impl-precedence.rs:19:20`
`3`	`3`	`\|`
`4`	`4`	`LL \| is_defaulted::<&'static u32>();`
`5`		- \| ^^^^^^^^^^^^ the trait `Signed` is not implemented for `&'static u32`, which is required by `&'static u32: Defaulted`
	`5`	+ \| ^^^^^^^^^^^^ the trait `Signed` is not implemented for `u32`, which is required by `&'static u32: Defaulted`
`6`	`6`	`\|`
`7`	`7`	note: required for `&'static u32` to implement `Defaulted`
`8`	`8`	`--> $DIR/typeck-default-trait-impl-precedence.rs:10:19`
Original file line number	Diff line number	Diff line change
@@ -2,7 +2,7 @@ error[E0277]: the trait bound `i32: Baz<Self>` is not satisfied
`2`	`2`	`--> $DIR/assume-gat-normalization-for-nested-goals.rs:9:30`
`3`	`3`	`\|`
`4`	`4`	`LL \| type Bar<T>: Baz<Self> = i32;`
`5`		- \| ^^^ the trait `Eq<i32>` is not implemented for `i32`, which is required by `i32: Baz<Self>`
	`5`	+ \| ^^^ the trait `Eq<i32>` is not implemented for `<Self as Foo>::Bar<()>`, which is required by `i32: Baz<Self>`
`6`	`6`	`\|`
`7`	`7`	note: required for `i32` to implement `Baz<Self>`
`8`	`8`	`--> $DIR/assume-gat-normalization-for-nested-goals.rs:16:23`
Original file line number	Diff line number	Diff line change
@@ -4,7 +4,7 @@ error[E0277]: `&'static (dyn Dummy + 'static)` cannot be sent between threads sa
`4`	`4`	`LL \| assert_send::<&'static (dyn Dummy + 'static)>();`
`5`	`5`	\| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&'static (dyn Dummy + 'static)` cannot be sent between threads safely
`6`	`6`	`\|`
`7`		- = help: the trait `Sync` is not implemented for `&'static (dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
	`7`	+ = help: the trait `Sync` is not implemented for `(dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
`8`	`8`	= note: required for `&'static (dyn Dummy + 'static)` to implement `Send`
`9`	`9`	note: required by a bound in `assert_send`
`10`	`10`	`--> $DIR/kindck-send-object.rs:5:18`
Original file line number	Diff line number	Diff line change
@@ -4,7 +4,7 @@ error[E0277]: `&'a (dyn Dummy + 'a)` cannot be sent between threads safely
`4`	`4`	`LL \| assert_send::<&'a dyn Dummy>();`
`5`	`5`	\| ^^^^^^^^^^^^^ `&'a (dyn Dummy + 'a)` cannot be sent between threads safely
`6`	`6`	`\|`
`7`		- = help: the trait `Sync` is not implemented for `&'a (dyn Dummy + 'a)`, which is required by `&'a (dyn Dummy + 'a): Send`
	`7`	+ = help: the trait `Sync` is not implemented for `(dyn Dummy + 'a)`, which is required by `&'a (dyn Dummy + 'a): Send`
`8`	`8`	= note: required for `&'a (dyn Dummy + 'a)` to implement `Send`
`9`	`9`	note: required by a bound in `assert_send`
`10`	`10`	`--> $DIR/kindck-send-object1.rs:5:18`
Original file line number	Diff line number	Diff line change
@@ -4,7 +4,7 @@ error[E0277]: `&'static (dyn Dummy + 'static)` cannot be sent between threads sa
`4`	`4`	`LL \| assert_send::<&'static dyn Dummy>();`
`5`	`5`	\| ^^^^^^^^^^^^^^^^^^ `&'static (dyn Dummy + 'static)` cannot be sent between threads safely
`6`	`6`	`\|`
`7`		- = help: the trait `Sync` is not implemented for `&'static (dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
	`7`	+ = help: the trait `Sync` is not implemented for `(dyn Dummy + 'static)`, which is required by `&'static (dyn Dummy + 'static): Send`
`8`	`8`	= note: required for `&'static (dyn Dummy + 'static)` to implement `Send`
`9`	`9`	note: required by a bound in `assert_send`
`10`	`10`	`--> $DIR/kindck-send-object2.rs:3:18`
Original file line number	Diff line number	Diff line change
`@@ -4,7 +4,7 @@ error: future cannot be sent between threads safely`
`4`	`4`	`LL \| is_send(foo());`
`5`	`5`	\| ^^^^^ future returned by `foo` is not `Send`
`6`	`6`	`\|`
`7`		- = help: the trait `Sync` is not implemented for `impl Future<Output = ()>`, which is required by `impl Future<Output = ()>: Send`
	`7`	+ = help: the trait `Sync` is not implemented for `NotSync`, which is required by `impl Future<Output = ()>: Send`
`8`	`8`	note: future is not `Send` as this value is used across an await
`9`	`9`	`--> $DIR/auto-with-drop_tracking_mir.rs:16:11`
`10`	`10`	`\|`
Original file line number	Diff line number	Diff line change
@@ -4,6 +4,11 @@ error[E0277]: the trait bound `(): Foo` is not satisfied
`4`	`4`	`LL \| needs_foo::<()>();`
`5`	`5`	\| ^^ the trait `Bar` is not implemented for `()`, which is required by `(): Foo`
`6`	`6`	`\|`
	`7`	`+help: this trait has no implementations, consider adding one`
	`8`	`+ --> $DIR/point-at-failing-nested.rs:4:1`
	`9`	`+ \|`
	`10`	`+LL \| trait Bar {}`
	`11`	`+ \| ^^^^^^^^^`
`7`	`12`	note: required for `()` to implement `Foo`
`8`	`13`	`--> $DIR/point-at-failing-nested.rs:9:12`
`9`	`14`	`\|`
Original file line number	Diff line number	Diff line change
`@@ -6,6 +6,11 @@ LL \| needs_foo(());`
`6`	`6`	`\| \|`
`7`	`7`	`\| required by a bound introduced by this call`
`8`	`8`	`\|`
	`9`	`+help: this trait has no implementations, consider adding one`
	`10`	`+ --> $DIR/where-clause-doesnt-apply.rs:2:1`
	`11`	`+ \|`
	`12`	`+LL \| trait Bar {}`
	`13`	`+ \| ^^^^^^^^^`
`9`	`14`	note: required for `()` to implement `Foo`
`10`	`15`	`--> $DIR/where-clause-doesnt-apply.rs:4:9`
`11`	`16`	`\|`