Report generic mismatches when calling bodyless trait functions

tests/ui/fn/error-recovery-mismatch.rs

@@ -0,0 +1,20 @@
+// Used to ICE due to a size mismatch between the actual fake signature of `fold` and the
+// generated signature used reporting the parameter mismatch at the call site.
+// See issue #135124
+
+trait A  {
+    fn y(&self)
+    {
+        fn call() -> impl Sized {}
+        self.fold(call(), call());
+    }
+    fn fold<T>(&self, _: T, &self._) {}
+    //~^ ERROR unexpected `self` parameter in function
+    //~| ERROR expected one of `)` or `,`, found `.`
+    //~| ERROR identifier `self` is bound more than once in this parameter list
+    //~| WARNING anonymous parameters are deprecated
+    //~| WARNING this is accepted in the current edition
+    //~| ERROR the placeholder `_` is not allowed within types
+}
+
+fn main() {}

tests/ui/fn/error-recovery-mismatch.stderr

@@ -0,0 +1,46 @@
+error: unexpected `self` parameter in function
+  --> $DIR/error-recovery-mismatch.rs:11:29
+   |
+LL |     fn fold<T>(&self, _: T, &self._) {}
+   |                             ^^^^^ must be the first parameter of an associated function
+
+error: expected one of `)` or `,`, found `.`
+  --> $DIR/error-recovery-mismatch.rs:11:34
+   |
+LL |     fn fold<T>(&self, _: T, &self._) {}
+   |                                  ^
+   |                                  |
+   |                                  expected one of `)` or `,`
+   |                                  help: missing `,`
+
+error[E0415]: identifier `self` is bound more than once in this parameter list
+  --> $DIR/error-recovery-mismatch.rs:11:30
+   |
+LL |     fn fold<T>(&self, _: T, &self._) {}
+   |                              ^^^^ used as parameter more than once
+
+warning: anonymous parameters are deprecated and will be removed in the next edition
+  --> $DIR/error-recovery-mismatch.rs:11:35
+   |
+LL |     fn fold<T>(&self, _: T, &self._) {}
+   |                                   ^ help: try naming the parameter or explicitly ignoring it: `_: _`
+   |
+   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
+   = note: for more information, see issue #41686 <https://github.com/rust-lang/rust/issues/41686>
+   = note: `#[warn(anonymous_parameters)]` on by default
+
+error[E0121]: the placeholder `_` is not allowed within types on item signatures for functions
+  --> $DIR/error-recovery-mismatch.rs:11:35
+   |
+LL |     fn fold<T>(&self, _: T, &self._) {}
+   |                                   ^ not allowed in type signatures
+   |
+help: use type parameters instead
+   |
+LL |     fn fold<T, U>(&self, _: T, &self.U) {}
+   |              +++                     ~
+
+error: aborting due to 4 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0121, E0415.
+For more information about an error, try `rustc --explain E0121`.

tests/ui/fn/param-mismatch-trait-fn.rs

@@ -0,0 +1,10 @@
+trait Foo {
+    fn same_type<T>(_: T, _: T);
+}
+
+fn f<T: Foo, X, Y>(x: X, y: Y) {
+    T::same_type([x], Some(y));
+    //~^ ERROR mismatched types
+}
+
+fn main() {}

tests/ui/fn/param-mismatch-trait-fn.stderr

@@ -0,0 +1,23 @@
+error[E0308]: mismatched types
+  --> $DIR/param-mismatch-trait-fn.rs:6:23
+   |
+LL |     T::same_type([x], Some(y));
+   |     ------------ ---  ^^^^^^^ expected `[X; 1]`, found `Option<Y>`
+   |     |            |
+   |     |            expected all arguments to be this `[X; 1]` type because they need to match the type of this parameter
+   |     arguments to this function are incorrect
+   |
+   = note: expected array `[X; 1]`
+               found enum `Option<Y>`
+note: associated function defined here
+  --> $DIR/param-mismatch-trait-fn.rs:2:8
+   |
+LL |     fn same_type<T>(_: T, _: T);
+   |        ^^^^^^^^^ -  -     - this parameter needs to match the `[X; 1]` type of parameter #1
+   |                  |  |
+   |                  |  parameter #2 needs to match the `[X; 1]` type of this parameter
+   |                  parameter #1 and parameter #2 both reference this parameter `T`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0308`.

tests/ui/methods/issues/issue-61525.stderr

@@ -32,7 +32,7 @@ note: method defined here
   --> $DIR/issue-61525.rs:2:8
    |
 LL |     fn query<Q>(self, q: Q);
-   |        ^^^^^
+   |        ^^^^^          -
 
 error: aborting due to 2 previous errors
 

tests/ui/suggestions/trait-with-missing-associated-type-restriction.stderr

@@ -94,7 +94,7 @@ note: method defined here
   --> $DIR/trait-with-missing-associated-type-restriction.rs:9:8
    |
 LL |     fn funk(&self, _: Self::A);
-   |        ^^^^
+   |        ^^^^        -
 help: consider constraining the associated type `<T as Trait<i32>>::A` to `{integer}`
    |
 LL | fn bar2<T: Trait<i32, A = {integer}>>(x: T) {

tests/ui/traits/issue-52893.stderr

@@ -22,7 +22,7 @@ note: method defined here
   --> $DIR/issue-52893.rs:11:8
    |
 LL |     fn push(self, other: T) -> Self::PushRes;
-   |        ^^^^
+   |        ^^^^       -----
 
 error: aborting due to 1 previous error