Auto merge of #108324 - notriddle:notriddle/assoc-fn-method, r=compiler-errors,davidtwco,estebank,oli-obk

diagnostics: if AssocFn has self argument, describe as method

Discussed in 329265515

This commit also changes the tooltips on rustdoc intra-doc links targeting methods.

For anyone not sure why this is being done, see the Reference definitions of these terms in <https://doc.rust-lang.org/1.67.1/reference/items/associated-items.html#methods>

> Associated functions whose first parameter is named `self` are called methods and may be invoked using the [method call operator](https://doc.rust-lang.org/1.67.1/reference/expressions/method-call-expr.html), for example, `x.foo()`, as well as the usual function call notation.

In particular, while this means it's technically correct for rustc to refer to a method as an associated function (and there are a few cases where it'll still do so), rustc *must never* use the term "method" to refer to an associated function that does not have a `self` parameter.

compiler/rustc_resolve/src/diagnostics.rs

@@ -189,7 +189,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
         }
 
         let container = match parent.kind {
-            ModuleKind::Def(kind, _, _) => kind.descr(parent.def_id()),
+            ModuleKind::Def(kind, _, _) => self.tcx.def_kind_descr(kind, parent.def_id()),
             ModuleKind::Block => "block",
         };
 
@@ -1804,7 +1804,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
                         found("module")
                     } else {
                         match binding.res() {
-                            Res::Def(kind, id) => found(kind.descr(id)),
+                            Res::Def(kind, id) => found(self.tcx.def_kind_descr(kind, id)),
                             _ => found(ns_to_try.descr()),
                         }
                     }