From 272c2ff15f40a0979c2509261e4843090cdddb92 Mon Sep 17 00:00:00 2001
From: Puck Meerburg <puck@puckipedia.com>
Date: Sat, 20 Apr 2024 13:08:42 +0000
Subject: [PATCH] remove extraneous cache entry from github fetcher

This isn't necessary, as it's already covered by the tarball fetcher's
cache.

Change-Id: I85e35f5a61594f27b8f30d82145f92c5d6559e1f
---
 src/libfetchers/github.cc     | 20 --------------------
 tests/nixos/github-flakes.nix |  7 +++++++
 2 files changed, 7 insertions(+), 20 deletions(-)

diff --git a/src/libfetchers/github.cc b/src/libfetchers/github.cc
index 291f457f0..6f997885d 100644
--- a/src/libfetchers/github.cc
+++ b/src/libfetchers/github.cc
@@ -195,32 +195,12 @@ struct GitArchiveInputScheme : InputScheme
         input.attrs.erase("ref");
         input.attrs.insert_or_assign("rev", rev->gitRev());
 
-        Attrs lockedAttrs({
-            {"type", "git-tarball"},
-            {"rev", rev->gitRev()},
-        });
-
-        if (auto res = getCache()->lookup(store, lockedAttrs)) {
-            input.attrs.insert_or_assign("lastModified", getIntAttr(res->first, "lastModified"));
-            return {std::move(res->second), input};
-        }
-
         auto url = getDownloadUrl(input);
 
         auto result = downloadTarball(store, url.url, input.getName(), true, url.headers);
 
         input.attrs.insert_or_assign("lastModified", uint64_t(result.lastModified));
 
-        getCache()->add(
-            store,
-            lockedAttrs,
-            {
-                {"rev", rev->gitRev()},
-                {"lastModified", uint64_t(result.lastModified)}
-            },
-            result.tree.storePath,
-            true);
-
         return {result.tree.storePath, input};
     }
 };
diff --git a/tests/nixos/github-flakes.nix b/tests/nixos/github-flakes.nix
index 4830be6ac..1954208b9 100644
--- a/tests/nixos/github-flakes.nix
+++ b/tests/nixos/github-flakes.nix
@@ -119,6 +119,9 @@ in
                 [ { urlPath = "/repos/NixOS/nixpkgs";
                     dir = nixpkgs-api;
                   }
+                  { urlPath = "/repos/fork/nixpkgs";
+                    dir = nixpkgs-api;
+                  }
                   { urlPath = "/repos/fancy-enterprise/private-flake";
                     dir = private-flake-api;
                   }
@@ -190,6 +193,10 @@ in
     client.succeed("nix registry pin nixpkgs")
     client.succeed("nix flake metadata nixpkgs --tarball-ttl 0 >&2")
 
+    # fetching a fork with the same commit ID should fail, even if the revision is cached
+    client.succeed("nix flake metadata github:NixOS/nixpkgs")
+    client.fail("nix flake metadata github:fork/nixpkgs")
+
     # Shut down the web server. The flake should be cached on the client.
     github.succeed("systemctl stop httpd.service")