From b3d57aff7a82016d56ef8ec11834284b4f4e59f3 Mon Sep 17 00:00:00 2001
From: Geoff Romer <gromer@google.com>
Date: Fri, 13 Feb 2026 14:44:23 -0800
Subject: [PATCH] Diagnose if a NodeIdOneOf argument isn't a typed node.
 (#6738)

---
 toolchain/parse/node_ids.h | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/toolchain/parse/node_ids.h b/toolchain/parse/node_ids.h
index 1347a20ea86f..58a437757cbb 100644
--- a/toolchain/parse/node_ids.h
+++ b/toolchain/parse/node_ids.h
@@ -113,9 +113,20 @@ using AnyRequirementId = NodeIdInCategory<NodeCategory::Requirement>;
 using AnyNonExprNameId = NodeIdInCategory<NodeCategory::NonExprName>;
 using AnyPackageNameId = NodeIdInCategory<NodeCategory::PackageName>;
 
+namespace Internal {
+template <typename T>
+concept IsNodeKind = std::same_as<std::remove_cvref_t<T>, NodeKind> ||
+                     std::same_as<std::remove_cvref_t<T>, NodeKind::Definition>;
+
+template <typename T>
+concept IsTypedNode = requires {
+  { T::Kind } -> IsNodeKind;
+};
+}  // namespace Internal
+
 // NodeId with kind that matches one of the `T::Kind`s.
 template <typename... T>
-  requires(sizeof...(T) >= 2)
+  requires(sizeof...(T) >= 2 && (Internal::IsTypedNode<T> && ...))
 struct NodeIdOneOf : public NodeId {
  private:
   // True if `OtherT` is one of `T`.