merge bare-fn-start.rs and trait-fn.rs into invalid-self-argument.rs

Author: reddevilmidzy

tests/ui/self/bare-fn-start.rs

@@ -1,5 +1,22 @@
-fn b(foo: u32, &mut self) { }
+//! regression test for <https://github.com/rust-lang/rust/issues/55972>
+
+fn a(&self) {}
+//~^ ERROR `self` parameter is only allowed in associated functions
+//~| NOTE not semantically valid as function parameter
+//~| NOTE associated functions are those in `impl` or `trait` definitions
+
+fn b(foo: u32, &mut self) {}
 //~^ ERROR unexpected `self` parameter in function
 //~| NOTE must be the first parameter of an associated function
 
-fn main() { }
+struct Foo {}
+
+impl Foo {
+    fn c(foo: u32, self) {}
+    //~^ ERROR unexpected `self` parameter in function
+    //~| NOTE must be the first parameter of an associated function
+
+    fn good(&mut self, foo: u32) {}
+}
+
+fn main() {}

tests/ui/self/bare-fn-start.stderr

@@ -1,8 +1,22 @@
 error: unexpected `self` parameter in function
-  --> $DIR/bare-fn.rs:1:16
+  --> $DIR/invalid-self-argument.rs:8:16
    |
-LL | fn b(foo: u32, &mut self) { }
+LL | fn b(foo: u32, &mut self) {}
    |                ^^^^^^^^^ must be the first parameter of an associated function
 
-error: aborting due to 1 previous error
+error: unexpected `self` parameter in function
+  --> $DIR/invalid-self-argument.rs:15:20
+   |
+LL |     fn c(foo: u32, self) {}
+   |                    ^^^^ must be the first parameter of an associated function
+
+error: `self` parameter is only allowed in associated functions
+  --> $DIR/invalid-self-argument.rs:3:6
+   |
+LL | fn a(&self) {}
+   |      ^^^^^ not semantically valid as function parameter
+   |
+   = note: associated functions are those in `impl` or `trait` definitions
+
+error: aborting due to 3 previous errors