From 6da6fbfbe940feb807eeef20035d6603448d4d5e Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Thu, 5 Jul 2007 20:33:04 +0000
Subject: [PATCH] * Properly keep packages during upgrades.

---
 src/nix-env/nix-env.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc
index 7733ab16b..9c78f0121 100644
--- a/src/nix-env/nix-env.cc
+++ b/src/nix-env/nix-env.cc
@@ -567,7 +567,10 @@ static void upgradeDerivations(Globals & globals,
         DrvName drvName(i->name);
 
         MetaInfo meta = i->queryMetaInfo(globals.state);
-        if (meta["keep"] == "true") continue;
+        if (meta["keep"] == "true") {
+            newElems.push_back(*i);
+            continue;
+        }
 
         /* Find the derivation in the input Nix expression with the
            same name that satisfies the version constraints specified