From 12f50b6510effe33b6d6322b4322ac0c9588d2e3 Mon Sep 17 00:00:00 2001
From: Sebastian Ullrich <sebasti@nullri.ch>
Date: Sun, 8 Aug 2021 13:24:13 +0200
Subject: [PATCH] Short-circuit querying substituters on success

---
 src/libstore/local-store.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 747eb205e..faabe4170 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -1076,6 +1076,10 @@ void LocalStore::querySubstitutablePathInfos(const StorePathCAMap & paths, Subst
     if (!settings.useSubstitutes) return;
     for (auto & sub : getDefaultSubstituters()) {
         for (auto & path : paths) {
+            if (infos.find(path.first) != infos.end())
+                // choose first succeeding substituter
+                continue;
+
             auto subPath(path.first);
 
             // recompute store path so that we can use a different store root