From 8e732cfac1e99dd53822c4e536d09e242ef9fd2a Mon Sep 17 00:00:00 2001
From: Matt Sturgeon <matt@sturgeon.me.uk>
Date: Fri, 28 Mar 2025 04:41:55 +0000
Subject: [PATCH] flake/dev: rename `nixpkgs` input to avoid shadowing

Rename `inputs.nixpkgs` to `inputs.dev-nixpkgs` to avoid shadowing the
root flake's `inputs.nixpkgs`.

Having the dev flake shadow an input can be confusing, since overriding
the root flake's input will have no effect when evaluating outputs that
depend on the dev partition.

The only reason we specify a `nixpkgs` input at all here, is so the
other inputs can follow it.

Once nix 2.26 is more prevalent, we can follow the root flake's inputs
using a `"path:../.."` input.
---
 .github/workflows/update.yml |  2 +-
 flake/dev/flake.nix          | 15 +++++++++------
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/update.yml b/.github/workflows/update.yml
index c29e0233..31c75141 100644
--- a/.github/workflows/update.yml
+++ b/.github/workflows/update.yml
@@ -126,7 +126,7 @@ jobs:
           root_nixpkgs=$(nix eval --raw --file . 'inputs.nixpkgs.rev')
           old=$(git show --no-patch --format=%h)
           nix flake update --commit-lock-file \
-              --override-input nixpkgs "github:NixOS/nixpkgs/$root_nixpkgs" \
+              --override-input 'dev-nixpkgs' "github:NixOS/nixpkgs/$root_nixpkgs" \
               --flake './flake/dev'
           new=$(git show --no-patch --format=%h)
           if [ "$old" != "$new" ]; then
diff --git a/flake/dev/flake.nix b/flake/dev/flake.nix
index dd213905..3390398c 100644
--- a/flake/dev/flake.nix
+++ b/flake/dev/flake.nix
@@ -2,33 +2,36 @@
   description = "Private inputs for development purposes. These are used by the top level flake in the `dev` partition, but do not appear in consumers' lock files.";
 
   inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    # NOTE: Use a different name to the root flake's inputs.nixpkgs to avoid shadowing it.
+    # NOTE: The only reason we specify a nixpkgs input at all here, is so the other inputs can follow it.
+    # TODO: Once nix 2.26 is more prevalent, follow the root flake's inputs using a "path:../.." input.
+    dev-nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
 
     home-manager = {
       url = "github:nix-community/home-manager";
-      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.nixpkgs.follows = "dev-nixpkgs";
     };
 
     nix-darwin = {
       url = "github:lnl7/nix-darwin";
-      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.nixpkgs.follows = "dev-nixpkgs";
     };
 
     devshell = {
       url = "github:numtide/devshell";
-      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.nixpkgs.follows = "dev-nixpkgs";
     };
 
     treefmt-nix = {
       url = "github:numtide/treefmt-nix";
-      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.nixpkgs.follows = "dev-nixpkgs";
     };
 
     flake-compat.url = "https://flakehub.com/f/edolstra/flake-compat/1.tar.gz";
 
     git-hooks = {
       url = "github:cachix/git-hooks.nix";
-      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.nixpkgs.follows = "dev-nixpkgs";
       inputs.flake-compat.follows = "flake-compat";
     };
   };