Move fn to proc-macro conversion to name classification

crates/ide/src/references.rs

@@ -1550,14 +1550,27 @@ fn func() {}
 
                 FileId(0) 16..24
             "#]],
-        )
+        );
+        check(
+            r#"
+#[proc_macro_attribute]
+fn func$0() {}
+"#,
+            expect![[r#"
+                func Attribute FileId(0) 0..36 27..31
+
+                (no references)
+            "#]],
+        );
     }
 
+    // FIXME
     #[test]
     fn derive() {
         check(
             r#"
 //- proc_macros: derive_identity
+//- minicore: derive
 
 #[derive(proc_macros::DeriveIdentity$0)]
 struct Foo;

crates/ide_db/src/defs.rs

@@ -225,7 +225,12 @@ impl NameClass {
                     Definition::Macro(sema.to_def(&ast::Macro::MacroDef(it))?)
                 }
                 ast::Item::Const(it) => Definition::Const(sema.to_def(&it)?),
-                ast::Item::Fn(it) => Definition::Function(sema.to_def(&it)?),
+                ast::Item::Fn(it) => {
+                    let def = sema.to_def(&it)?;
+                    def.as_proc_macro(sema.db)
+                        .map(Definition::Macro)
+                        .unwrap_or(Definition::Function(def))
+                }
                 ast::Item::Module(it) => Definition::Module(sema.to_def(&it)?),
                 ast::Item::Static(it) => Definition::Static(sema.to_def(&it)?),
                 ast::Item::Trait(it) => Definition::Trait(sema.to_def(&it)?),

crates/ide_db/src/search.rs

@@ -309,14 +309,13 @@ impl Definition {
     }
 
     pub fn usages<'a>(self, sema: &'a Semantics<RootDatabase>) -> FindUsages<'a> {
-        let def = match self {
+        FindUsages {
-            def @ Definition::Function(f) => {
+            def: self,
-                // search for proc-macro usages if this function describes a proc macro
+            sema,
-                f.as_proc_macro(sema.db).map(Definition::Macro).unwrap_or(def)
+            scope: None,
-            }
+            include_self_kw_refs: None,
-            def => def,
+            search_self_mod: false,
-        };
+        }
-        FindUsages { def, sema, scope: None, include_self_kw_refs: None, search_self_mod: false }
     }
 }