1 files changed, 14 insertions, 0 deletions
diff --git a/src/access/rules.rs b/src/access/rules.rs
index bef9a13..ac7377f 100644
--- a/src/access/rules.rs
+++ b/src/access/rules.rs
@@ -109,6 +109,20 @@ impl Reads {
     }
 }
 
+impl Reads {
+    /// Whether the policy at `seen` requires changes signed (`Policy::required`): read
+    /// once for the heads, as `judge_reading` reads it. False if `doc` lacks one of them.
+    pub(crate) fn required(&mut self, doc: &Document, seen: &[ChangeHash]) -> bool {
+        let Some(at) = At::new(doc, seen) else {
+            return false;
+        };
+        self.at(seen)
+            .policy
+            .get_or_insert_with(|| super::policy::of(&at))
+            .required()
+    }
+}
+
 /// Judges `change`, about to be applied to `doc` (of `epoch`).
 pub(crate) fn judge(doc: &Document, epoch: Epoch, change: &Change<'_>) -> Result<(), Refusal> {
     judge_reading(doc, epoch, change, &mut Reads::default())