Rollup merge of #60388 - cramertj:elided-lifetime-async, r=nikomatsakis

Disallow non-explicit elided lifetimes in async fn

Fix https://github.com/rust-lang/rust/issues/60203

r? @nikomatsakis

src/test/ui/async-fn-path-elision.rs

@@ -0,0 +1,16 @@
+// edition:2018
+
+#![feature(async_await, await_macro)]
+#![allow(dead_code)]
+
+struct HasLifetime<'a>(&'a bool);
+
+async fn error(lt: HasLifetime) { //~ ERROR implicit elided lifetime not allowed here
+    if *lt.0 {}
+}
+
+fn no_error(lt: HasLifetime) {
+    if *lt.0 {}
+}
+
+fn main() {}

src/test/ui/async-fn-path-elision.stderr

@@ -0,0 +1,8 @@
+error[E0726]: implicit elided lifetime not allowed here
+  --> $DIR/async-fn-path-elision.rs:8:20
+   |
+LL | async fn error(lt: HasLifetime) {
+   |                    ^^^^^^^^^^^- help: indicate the anonymous lifetime: `<'_>`
+
+error: aborting due to previous error
+

src/test/ui/impl-header-lifetime-elision/path-elided.rs

@@ -5,7 +5,7 @@ trait MyTrait { }
 struct Foo<'a> { x: &'a u32 }
 
 impl MyTrait for Foo {
-    //~^ ERROR missing lifetime specifier
+    //~^ ERROR implicit elided lifetime not allowed here
 }
 
 fn main() {}

src/test/ui/impl-header-lifetime-elision/path-elided.stderr

@@ -1,9 +1,8 @@
-error[E0106]: missing lifetime specifier
+error[E0726]: implicit elided lifetime not allowed here
   --> $DIR/path-elided.rs:7:18
    |
 LL | impl MyTrait for Foo {
-   |                  ^^^ expected lifetime parameter
+   |                  ^^^- help: indicate the anonymous lifetime: `<'_>`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0106`.

src/test/ui/impl-header-lifetime-elision/trait-elided.rs

@@ -3,7 +3,7 @@
 trait MyTrait<'a> { }
 
 impl MyTrait for u32 {
-    //~^ ERROR missing lifetime specifier
+    //~^ ERROR implicit elided lifetime not allowed here
 }
 
 fn main() {}

src/test/ui/impl-header-lifetime-elision/trait-elided.stderr

@@ -1,9 +1,8 @@
-error[E0106]: missing lifetime specifier
+error[E0726]: implicit elided lifetime not allowed here
   --> $DIR/trait-elided.rs:5:6
    |
 LL | impl MyTrait for u32 {
-   |      ^^^^^^^ expected lifetime parameter
+   |      ^^^^^^^- help: indicate the anonymous lifetime: `<'_>`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0106`.

src/test/ui/issues/issue-10412.rs

@@ -5,7 +5,8 @@ trait Serializable<'self, T> { //~ ERROR lifetimes cannot use keyword names
 
 impl<'self> Serializable<str> for &'self str { //~ ERROR lifetimes cannot use keyword names
     //~^ ERROR lifetimes cannot use keyword names
-    //~| ERROR missing lifetime specifier
+    //~| ERROR implicit elided lifetime not allowed here
+    //~| ERROR the size for values of type `str` cannot be known at compilation time
     fn serialize(val : &'self str) -> Vec<u8> { //~ ERROR lifetimes cannot use keyword names
         vec![1]
     }

src/test/ui/issues/issue-10412.stderr

@@ -29,23 +29,32 @@ LL | impl<'self> Serializable<str> for &'self str {
    |                                    ^^^^^
 
 error: lifetimes cannot use keyword names
-  --> $DIR/issue-10412.rs:9:25
+  --> $DIR/issue-10412.rs:10:25
    |
 LL |     fn serialize(val : &'self str) -> Vec<u8> {
    |                         ^^^^^
 
 error: lifetimes cannot use keyword names
-  --> $DIR/issue-10412.rs:12:37
+  --> $DIR/issue-10412.rs:13:37
    |
 LL |     fn deserialize(repr: &[u8]) -> &'self str {
    |                                     ^^^^^
 
-error[E0106]: missing lifetime specifier
+error[E0726]: implicit elided lifetime not allowed here
   --> $DIR/issue-10412.rs:6:13
    |
 LL | impl<'self> Serializable<str> for &'self str {
-   |             ^^^^^^^^^^^^^^^^^ expected lifetime parameter
+   |             ^^^^^^^^^^^^^^^^^ help: indicate the anonymous lifetime: `Serializable<'_, str>`
 
-error: aborting due to 8 previous errors
+error[E0277]: the size for values of type `str` cannot be known at compilation time
+  --> $DIR/issue-10412.rs:6:13
+   |
+LL | impl<'self> Serializable<str> for &'self str {
+   |             ^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `std::marker::Sized` is not implemented for `str`
+   = note: to learn more, visit <https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait>
 
-For more information about this error, try `rustc --explain E0106`.
+error: aborting due to 9 previous errors
+
+For more information about this error, try `rustc --explain E0277`.