feat(nix/sparseTree): add optional `name` argument r/6472

This allows pinning the name of the sparse tree derivation, which
stops the continous rebuilding of tvix-store-proto dependents.

I've opted to let the function take an attribute set instead and
refactored the call sites appropriately.

Change-Id: I3e57785094b1adbfffa24caf9f1c3384844fa200
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8965
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>

5 files changed, 68 insertions, 42 deletions

diff --git a/nix/sparseTree/default.nix b/nix/sparseTree/default.nix
index 7bfa47237869..35fa459e1c2f 100644
--- a/nix/sparseTree/default.nix
+++ b/nix/sparseTree/default.nix
@@ -2,22 +2,33 @@
 # and directories if they are listed in a supplied list:
 #
 # # A very minimal depot
-# sparseTree ./depot [
-#   ./default.nix
-#   ./depot/nix/readTree/default.nix
-#   ./third_party/nixpkgs
-#   ./third_party/overlays
-# ]
+# sparseTree {
+#   root = ./depot;
+#   paths = [
+#     ./default.nix
+#     ./depot/nix/readTree/default.nix
+#     ./third_party/nixpkgs
+#     ./third_party/overlays
+#   ];
+# }
 { pkgs, lib, ... }:
 
-# root path to use as a reference point
-root:
-# list of paths below `root` that should be
-# included in the resulting directory
-#
-# If path, need to refer to the actual file / directory to be included.
-# If a string, it is treated as a string relative to the root.
-paths:
+{
+  # root path to use as a reference point
+  root
+, # list of paths below `root` that should be
+  # included in the resulting directory
+  #
+  # If path, need to refer to the actual file / directory to be included.
+  # If a string, it is treated as a string relative to the root.
+  paths
+, # (optional) name to use for the derivation
+  #
+  # This should always be set when using roots that do not have
+  # controlled names, such as when passing the top-level of a git
+  # repository (e.g. `depot.path.origSrc`).
+  name ? builtins.baseNameOf root
+}:
 
 let
   rootLength = builtins.stringLength (toString root);
@@ -63,7 +74,7 @@ in
 
 # TODO(sterni): teach readTree to also read symlinked directories,
   # so we ln -sT instead of cp -aT.
-pkgs.runCommand "sparse-${builtins.baseNameOf root}" { } (
+pkgs.runCommand "sparse-${name}" { } (
   lib.concatMapStrings
     ({ src, dst }: ''
       mkdir -p "$(dirname "$out${dst}")"
diff --git a/tvix/store/protos/default.nix b/tvix/store/protos/default.nix
index 0ffdcac0418a..d5c44842229d 100644
--- a/tvix/store/protos/default.nix
+++ b/tvix/store/protos/default.nix
@@ -9,4 +9,8 @@ let
   protoFileNames = filter (hasSuffix ".proto") (attrNames (readDir ./.));
   protoFiles = map (f: ./. + ("/" + f)) protoFileNames;
 in
-depot.nix.sparseTree depot.path.origSrc protoFiles
+depot.nix.sparseTree {
+  name = "tvix-store-protos";
+  root = depot.path.origSrc;
+  paths = protoFiles;
+}
diff --git a/users/grfn/xanthous/server/default.nix b/users/grfn/xanthous/server/default.nix
index fbb5ccd26920..572230a56c5e 100644
--- a/users/grfn/xanthous/server/default.nix
+++ b/users/grfn/xanthous/server/default.nix
@@ -10,10 +10,13 @@ depot.third_party.naersk.buildPackage {
 
   # Workaround for a potential Nix bug related to restricted eval.
   # See https://github.com/nix-community/naersk/issues/169
-  root = depot.nix.sparseTree ./. [
-    ./Cargo.toml
-    ./Cargo.lock
-  ];
+  root = depot.nix.sparseTree {
+    root = ./.;
+    paths = [
+      ./Cargo.toml
+      ./Cargo.lock
+    ];
+  };
 
   passthru = {
     docker = import ./docker.nix args;
diff --git a/users/tazjin/tgsa/default.nix b/users/tazjin/tgsa/default.nix
index e413c99116fb..063781047a74 100644
--- a/users/tazjin/tgsa/default.nix
+++ b/users/tazjin/tgsa/default.nix
@@ -1,11 +1,14 @@
 { depot, pkgs, ... }:
 
 depot.third_party.naersk.buildPackage {
-  src = depot.nix.sparseTree ./. [
-    ./Cargo.lock
-    ./Cargo.toml
-    ./src
-  ];
+  src = depot.nix.sparseTree {
+    root = ./.;
+    paths = [
+      ./Cargo.lock
+      ./Cargo.toml
+      ./src
+    ];
+  };
 
   buildInputs = with pkgs; [
     pkg-config
diff --git a/web/bubblegum/default.nix b/web/bubblegum/default.nix
index 528d73032ba6..ed9ab616804d 100644
--- a/web/bubblegum/default.nix
+++ b/web/bubblegum/default.nix
@@ -10,23 +10,28 @@ let
     nint
     ;
 
-  minimalDepot = sparseTree depot.path.origSrc [
-    # general depot things
-    "default.nix"
-    "nix/readTree"
-    # nixpkgs for lib and packages
-    "third_party/nixpkgs"
-    "third_party/overlays"
-    # bubblegum and its dependencies
-    "web/bubblegum"
-    "nix/runExecline"
-    "nix/utils"
-    "nix/sparseTree"
-    # tvix docs for svg demo
-    "tvix/docs"
-    # for blog.nix
-    "users/sterni/nix"
-  ];
+  minimalDepot = sparseTree {
+    root = depot.path.origSrc;
+    name = "minimal-depot";
+
+    paths = [
+      # general depot things
+      "default.nix"
+      "nix/readTree"
+      # nixpkgs for lib and packages
+      "third_party/nixpkgs"
+      "third_party/overlays"
+      # bubblegum and its dependencies
+      "web/bubblegum"
+      "nix/runExecline"
+      "nix/utils"
+      "nix/sparseTree"
+      # tvix docs for svg demo
+      "tvix/docs"
+      # for blog.nix
+      "users/sterni/nix"
+    ];
+  };
 
   statusCodes = {
     # 1xx