Merge #6934

6934: Implement `cfg_attr` handling r=jonas-schievink a=jonas-schievink

Part of https://github.com/rust-analyzer/rust-analyzer/issues/5548

Co-authored-by: Jonas Schievink <[email protected]>

1 files changed, 18 insertions, 0 deletions

diff --git a/crates/hir_def/src/nameres/tests/diagnostics.rs b/crates/hir_def/src/nameres/tests/diagnostics.rs
index 1a7b98831..58d69d3c6 100644
--- a/crates/hir_def/src/nameres/tests/diagnostics.rs
+++ b/crates/hir_def/src/nameres/tests/diagnostics.rs
@@ -1,4 +1,5 @@
 use base_db::fixture::WithFixture;
+use test_utils::mark;
 
 use crate::test_db::TestDB;
 
@@ -119,3 +120,20 @@ fn inactive_item() {
         "#,
     );
 }
+
+/// Tests that `cfg` attributes behind `cfg_attr` is handled properly.
+#[test]
+fn inactive_via_cfg_attr() {
+    mark::check!(cfg_attr_active);
+    check_diagnostics(
+        r#"
+        //- /lib.rs
+          #[cfg_attr(not(never), cfg(no))] fn f() {}
+        //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ code is inactive due to #[cfg] directives: no is disabled
+
+          #[cfg_attr(not(never), cfg(not(no)))] fn f() {}
+
+          #[cfg_attr(never, cfg(no))] fn g() {}
+        "#,
+    );
+}