Update tests

src/test/rustdoc/macro-document-private-duplicate.rs

@@ -0,0 +1,23 @@
+// FIXME: If two macros in the same module have the same name
+// (yes, that's a thing), rustdoc lists both of them on the index page,
+// but only documents the first one on the page for the macro.
+// Fortunately, this can only happen in document private items mode,
+// but it still isn't ideal beahvior.
+//
+// See https://github.com/rust-lang/rust/pull/88019#discussion_r693920453
+//
+// compile-flags: --document-private-items
+
+// @has macro_document_private_duplicate/index.html 'Doc 1.'
+// @has macro_document_private_duplicate/macro.a_macro.html 'Doc 1.'
+/// Doc 1.
+macro_rules! a_macro {
+    () => ()
+}
+
+// @has macro_document_private_duplicate/index.html 'Doc 2.'
+// @!has macro_document_private_duplicate/macro.a_macro.html 'Doc 2.'
+/// Doc 2.
+macro_rules! a_macro {
+    () => ()
+}