From 3402b650cdce318e42acd4dc34f42423cafef587 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Wed, 7 Jun 2023 15:06:12 +0200
Subject: [PATCH] Add a generic check for rev attribute mismatches

---
 src/libfetchers/fetchers.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/libfetchers/fetchers.cc b/src/libfetchers/fetchers.cc
index 91db3a9eb..2860c1ceb 100644
--- a/src/libfetchers/fetchers.cc
+++ b/src/libfetchers/fetchers.cc
@@ -159,6 +159,12 @@ std::pair<Tree, Input> Input::fetch(ref<Store> store) const
                 input.to_string(), *prevLastModified);
     }
 
+    if (auto prevRev = getRev()) {
+        if (input.getRev() != prevRev)
+            throw Error("'rev' attribute mismatch in input '%s', expected %s",
+                input.to_string(), prevRev->gitRev());
+    }
+
     if (auto prevRevCount = getRevCount()) {
         if (input.getRevCount() != prevRevCount)
             throw Error("'revCount' attribute mismatch in input '%s', expected %d",