From 5406256d78244cf838eb917c35895035cbe1e402 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Mon, 8 May 2023 17:30:17 -0400
Subject: [PATCH] Specialize `LocalOverlayStore::queryPathInfoUncached`

---
 src/libstore/local-overlay-store.cc | 26 ++++++++++++++++++++++++++
 src/libstore/local-overlay-store.hh |  3 +++
 2 files changed, 29 insertions(+)

diff --git a/src/libstore/local-overlay-store.cc b/src/libstore/local-overlay-store.cc
index 2e3564df9..545e8d28f 100644
--- a/src/libstore/local-overlay-store.cc
+++ b/src/libstore/local-overlay-store.cc
@@ -1,4 +1,5 @@
 #include "local-overlay-store.hh"
+#include "callback.hh"
 
 namespace nix {
 
@@ -26,6 +27,31 @@ void LocalOverlayStore::registerDrvOutput(const Realisation & info)
 }
 
 
+void LocalOverlayStore::queryPathInfoUncached(const StorePath & path,
+    Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept
+{
+
+    auto callbackPtr = std::make_shared<decltype(callback)>(std::move(callback));
+
+    // If we don't have it, check lower store
+    LocalStore::queryPathInfoUncached(path,
+        {[this, path, callbackPtr](std::future<std::shared_ptr<const ValidPathInfo>> fut) {
+            try {
+                (*callbackPtr)(fut.get());
+            } catch (...) {
+                lowerStore->queryPathInfo(path,
+                    {[path, callbackPtr](std::future<ref<const ValidPathInfo>> fut) {
+                        try {
+                            (*callbackPtr)(fut.get().get_ptr());
+                        } catch (...) {
+                            callbackPtr->rethrow();
+                        }
+                    }});
+            }
+        }});
+}
+
+
 static RegisterStoreImplementation<LocalOverlayStore, LocalOverlayStoreConfig> regLocalOverlayStore;
 
 }
diff --git a/src/libstore/local-overlay-store.hh b/src/libstore/local-overlay-store.hh
index e5329f5d9..12b705efb 100644
--- a/src/libstore/local-overlay-store.hh
+++ b/src/libstore/local-overlay-store.hh
@@ -71,6 +71,9 @@ private:
     // Overridden methods…
 
     void registerDrvOutput(const Realisation & info) override;
+
+    void queryPathInfoUncached(const StorePath & path,
+        Callback<std::shared_ptr<const ValidPathInfo>> callback) noexcept override;
 };
 
 }