Auto merge of #89028 - Aaron1011:coercion-cause, r=nagisa

Propagate coercion cause into `try_coerce`

Currently, `coerce_inner` discards its `ObligationCause`
when calling `try_coerce`. This interfers with other
diagnostc improvements I'm working on, since we will lose
the original span by the time the actual coercion occurs.

Additionally, we now use the span of the trailing expression
(rather than the span of the entire function) when performing
a coercion in `check_return_expr`. This currently has no visible
effect on any of the unit tests, but will unblock future
diagnostic improvements.

11 files changed, 14 insertions, 14 deletions

diff --git a/src/test/ui/issues/issue-55796.stderr b/src/test/ui/issues/issue-55796.stderr
index ffe3bb737ad..952159ffc3b 100644
--- a/src/test/ui/issues/issue-55796.stderr
+++ b/src/test/ui/issues/issue-55796.stderr
@@ -15,7 +15,7 @@ note: ...so that the type `Map<<Self as Graph<'a>>::EdgesIter, [closure@$DIR/iss
 LL |         Box::new(self.out_edges(u).map(|e| e.target()))
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = note: but, the lifetime must be valid for the static lifetime...
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/issue-55796.rs:18:9
    |
 LL |         Box::new(self.out_edges(u).map(|e| e.target()))
@@ -40,7 +40,7 @@ note: ...so that the type `Map<<Self as Graph<'a>>::EdgesIter, [closure@$DIR/iss
 LL |         Box::new(self.in_edges(u).map(|e| e.target()))
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    = note: but, the lifetime must be valid for the static lifetime...
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/issue-55796.rs:23:9
    |
 LL |         Box::new(self.in_edges(u).map(|e| e.target()))
diff --git a/src/test/ui/issues/issue-75777.stderr b/src/test/ui/issues/issue-75777.stderr
index 16249a33c2f..25562f6347e 100644
--- a/src/test/ui/issues/issue-75777.stderr
+++ b/src/test/ui/issues/issue-75777.stderr
@@ -17,7 +17,7 @@ LL |     Box::new(move |_| fut)
    = note: expected `(Pin<Box<dyn Future<Output = A> + Send>>,)`
               found `(Pin<Box<(dyn Future<Output = A> + Send + 'a)>>,)`
    = note: but, the lifetime must be valid for the static lifetime...
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/issue-75777.rs:13:5
    |
 LL |     Box::new(move |_| fut)
diff --git a/src/test/ui/nll/issue-55394.stderr b/src/test/ui/nll/issue-55394.stderr
index 36721f923f7..dbc478e5b4c 100644
--- a/src/test/ui/nll/issue-55394.stderr
+++ b/src/test/ui/nll/issue-55394.stderr
@@ -19,7 +19,7 @@ note: but, the lifetime must be valid for the lifetime `'_` as defined on the im
    |
 LL | impl Foo<'_> {
    |          ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/issue-55394.rs:9:9
    |
 LL |         Foo { bar }
diff --git a/src/test/ui/nll/type-alias-free-regions.stderr b/src/test/ui/nll/type-alias-free-regions.stderr
index 6498ecfbe6f..dbb63b71af8 100644
--- a/src/test/ui/nll/type-alias-free-regions.stderr
+++ b/src/test/ui/nll/type-alias-free-regions.stderr
@@ -21,7 +21,7 @@ note: but, the lifetime must be valid for the lifetime `'a` as defined on the im
    |
 LL | impl<'a> FromBox<'a> for C<'a> {
    |      ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/type-alias-free-regions.rs:17:9
    |
 LL |         C { f: b }
@@ -52,7 +52,7 @@ note: but, the lifetime must be valid for the lifetime `'a` as defined on the im
    |
 LL | impl<'a> FromTuple<'a> for C<'a> {
    |      ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/type-alias-free-regions.rs:27:9
    |
 LL |         C { f: Box::new(b.0) }
diff --git a/src/test/ui/object-lifetime/object-lifetime-default-elision.stderr b/src/test/ui/object-lifetime/object-lifetime-default-elision.stderr
index 79ded5fc875..ee1a4612572 100644
--- a/src/test/ui/object-lifetime/object-lifetime-default-elision.stderr
+++ b/src/test/ui/object-lifetime/object-lifetime-default-elision.stderr
@@ -19,7 +19,7 @@ note: but, the lifetime must be valid for the lifetime `'b` as defined on the fu
    |
 LL | fn load3<'a,'b>(ss: &'a dyn SomeTrait) -> &'b dyn SomeTrait {
    |             ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/object-lifetime-default-elision.rs:71:5
    |
 LL |     ss
@@ -48,7 +48,7 @@ note: but, the lifetime must be valid for the lifetime `'b` as defined on the fu
    |
 LL | fn load3<'a,'b>(ss: &'a dyn SomeTrait) -> &'b dyn SomeTrait {
    |             ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/object-lifetime-default-elision.rs:71:5
    |
 LL |     ss
diff --git a/src/test/ui/regions/region-object-lifetime-in-coercion.stderr b/src/test/ui/regions/region-object-lifetime-in-coercion.stderr
index 1c8840f540e..852ca0f21b1 100644
--- a/src/test/ui/regions/region-object-lifetime-in-coercion.stderr
+++ b/src/test/ui/regions/region-object-lifetime-in-coercion.stderr
@@ -69,7 +69,7 @@ note: but, the lifetime must be valid for the lifetime `'b` as defined on the fu
    |
 LL | fn d<'a,'b>(v: &'a [u8]) -> Box<dyn Foo+'b> {
    |         ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/region-object-lifetime-in-coercion.rs:23:5
    |
 LL |     Box::new(v)
diff --git a/src/test/ui/regions/regions-close-over-type-parameter-multiple.stderr b/src/test/ui/regions/regions-close-over-type-parameter-multiple.stderr
index 0cce89215d3..bf29c76a0f0 100644
--- a/src/test/ui/regions/regions-close-over-type-parameter-multiple.stderr
+++ b/src/test/ui/regions/regions-close-over-type-parameter-multiple.stderr
@@ -19,7 +19,7 @@ note: but, the lifetime must be valid for the lifetime `'c` as defined on the fu
    |
 LL | fn make_object_bad<'a,'b,'c,A:SomeTrait+'a+'b>(v: A) -> Box<dyn SomeTrait + 'c> {
    |                          ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/regions-close-over-type-parameter-multiple.rs:20:5
    |
 LL |     box v as Box<dyn SomeTrait + 'a>
diff --git a/src/test/ui/regions/regions-creating-enums4.stderr b/src/test/ui/regions/regions-creating-enums4.stderr
index b24db1df18b..44bd88e01a2 100644
--- a/src/test/ui/regions/regions-creating-enums4.stderr
+++ b/src/test/ui/regions/regions-creating-enums4.stderr
@@ -21,7 +21,7 @@ note: but, the lifetime must be valid for the lifetime `'b` as defined on the fu
    |
 LL | fn mk_add_bad2<'a,'b>(x: &'a Ast<'a>, y: &'a Ast<'a>, z: &Ast) -> Ast<'b> {
    |                   ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/regions-creating-enums4.rs:7:5
    |
 LL |     Ast::Add(x, y)
diff --git a/src/test/ui/regions/regions-ret-borrowed-1.stderr b/src/test/ui/regions/regions-ret-borrowed-1.stderr
index bba968cfde4..b5b54bc3c8b 100644
--- a/src/test/ui/regions/regions-ret-borrowed-1.stderr
+++ b/src/test/ui/regions/regions-ret-borrowed-1.stderr
@@ -9,7 +9,7 @@ note: first, the lifetime cannot outlive the anonymous lifetime #1 defined on th
    |
 LL |     with(|o| o)
    |          ^^^^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/regions-ret-borrowed-1.rs:10:14
    |
 LL |     with(|o| o)
diff --git a/src/test/ui/regions/regions-ret-borrowed.stderr b/src/test/ui/regions/regions-ret-borrowed.stderr
index 4b93ca0ae67..debae47d16d 100644
--- a/src/test/ui/regions/regions-ret-borrowed.stderr
+++ b/src/test/ui/regions/regions-ret-borrowed.stderr
@@ -9,7 +9,7 @@ note: first, the lifetime cannot outlive the anonymous lifetime #1 defined on th
    |
 LL |     with(|o| o)
    |          ^^^^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/regions-ret-borrowed.rs:13:14
    |
 LL |     with(|o| o)
diff --git a/src/test/ui/regions/regions-trait-object-subtyping.stderr b/src/test/ui/regions/regions-trait-object-subtyping.stderr
index 7478b53bd3c..f16dfdd6e8c 100644
--- a/src/test/ui/regions/regions-trait-object-subtyping.stderr
+++ b/src/test/ui/regions/regions-trait-object-subtyping.stderr
@@ -36,7 +36,7 @@ note: but, the lifetime must be valid for the lifetime `'b` as defined on the fu
    |
 LL | fn foo3<'a,'b>(x: &'a mut dyn Dummy) -> &'b mut dyn Dummy {
    |            ^^
-note: ...so that the expression is assignable
+note: ...so that the types are compatible
   --> $DIR/regions-trait-object-subtyping.rs:15:5
    |
 LL |     x