From f62aafa79f0a39dd9a0f539e5f0d73dd35b2ebb2 Mon Sep 17 00:00:00 2001
From: Yuya Nishihara <yuya@tcha.org>
Date: Fri, 4 Nov 2022 20:28:03 +0900
Subject: [PATCH] repo: comment about safety implication of view/view_dirty

---
 lib/src/repo.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/src/repo.rs b/lib/src/repo.rs
index e1899e9c7..f5d2d1c3b 100644
--- a/lib/src/repo.rs
+++ b/lib/src/repo.rs
@@ -506,6 +506,10 @@ impl MutableRepo {
     }
 
     pub fn view(&self) -> &View {
+        // SAFETY: We don't really rely on runtime Ref/RefMut tracking. Since view_dirty
+        // is set only by &mut self functions, and view() is the solo function which
+        // publicly provides view-related reference, there should be no view reference
+        // alive if view_dirty == true.
         self.enforce_view_invariants();
         let view_borrow = self.view.borrow();
         let view = view_borrow.deref();