From 5ebcd1913c0f37e657e78e483fbaf147db1d9d15 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Tue, 10 Dec 2024 22:01:43 +0000
Subject: [PATCH] Add test for rustc-cfg-placeholder interaction with
 proc-macro

Ensure that the cfg-placeholder isn't visible by proc-macros.
---
 .../proc-macro/auxiliary/cfg-placeholder.rs   | 28 +++++++++++++++++++
 ...ttr-placeholder-invisible-to-proc-macro.rs | 13 +++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 tests/ui/proc-macro/auxiliary/cfg-placeholder.rs
 create mode 100644 tests/ui/proc-macro/cfg-attr-placeholder-invisible-to-proc-macro.rs

diff --git a/tests/ui/proc-macro/auxiliary/cfg-placeholder.rs b/tests/ui/proc-macro/auxiliary/cfg-placeholder.rs
new file mode 100644
index 0000000000000..f28dff50e2f6b
--- /dev/null
+++ b/tests/ui/proc-macro/auxiliary/cfg-placeholder.rs
@@ -0,0 +1,28 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+
+#[proc_macro_attribute]
+pub fn my_proc_macro(_: TokenStream, input: TokenStream) -> TokenStream {
+    if format!("{input:#?}").contains("my_attr1") {
+        panic!("found gated attribute my_attr1");
+    }
+    if !format!("{input:#?}").contains("my_attr2") {
+        panic!("didn't if gated my_attr2");
+    }
+    input
+}
+
+#[proc_macro_attribute]
+pub fn my_attr1(_: TokenStream, input: TokenStream) -> TokenStream {
+    panic!("my_attr1 was called");
+    input
+}
+
+#[proc_macro_attribute]
+pub fn my_attr2(_: TokenStream, input: TokenStream) -> TokenStream {
+    if format!("{input:#?}").contains("my_attr1") {
+        panic!("found gated attribute my_attr1");
+    }
+    input
+}
diff --git a/tests/ui/proc-macro/cfg-attr-placeholder-invisible-to-proc-macro.rs b/tests/ui/proc-macro/cfg-attr-placeholder-invisible-to-proc-macro.rs
new file mode 100644
index 0000000000000..62cac78788367
--- /dev/null
+++ b/tests/ui/proc-macro/cfg-attr-placeholder-invisible-to-proc-macro.rs
@@ -0,0 +1,13 @@
+// Ensure that `rustc-cfg-placeholder` isn't visible to proc-macros.
+//@proc-macro: cfg-placeholder.rs
+//@check-pass
+#![feature(cfg_eval)]
+#[macro_use] extern crate cfg_placeholder;
+
+#[cfg_eval]
+#[my_proc_macro]
+#[cfg_attr(FALSE, my_attr1)]
+#[cfg_attr(all(), my_attr2)]
+struct S {}
+
+fn main() {}