chore: add some tests

Signed-off-by: Drew Hess <[email protected]>

flake.nix

@@ -159,7 +159,9 @@
           })
           // haskellNixFlake.packages;
 
-          checks = haskellNixFlake.checks;
+          checks = {
+            inherit (pkgs) nix-buildkite-tests;
+          } // haskellNixFlake.checks;
 
           apps =
             let
@@ -246,6 +248,7 @@
                     nodejs-18_x
 
                     nixpkgs-fmt
+                    goldplate
                   ]);
 
                   shellHook = ''
@@ -297,12 +300,18 @@
                 };
               };
 
+              nix-buildkite-tests = final.callPackage ./nix/pkgs/nix-buildkite-tests {
+                src = ./tests;
+              };
             in
             {
-              inherit nix-buildkite-plugin;
+              inherit (final.haskellPackages) goldplate;
 
+              inherit nix-buildkite-plugin;
               nix-buildkite = nixBuildkiteFlake.packages."nix-buildkite-plugin:exe:nix-buildkite";
               inherit nix-buildkite-docker-image;
+
+              inherit nix-buildkite-tests;
             }
           );
 

nix/pkgs/nix-buildkite-tests/default.nix

@@ -0,0 +1,20 @@
+{ goldplate
+, nix
+, nix-buildkite
+, runCommand
+, src
+}:
+runCommand "nix-buildkite-tests"
+{
+  inherit src;
+  nativeBuildInputs = [
+    goldplate
+    nix
+    nix-buildkite
+  ];
+} ''
+  set -e
+  cd $src
+  goldplate -j2 --pretty-diff .
+  touch $out
+''

tests/default.nix

@@ -0,0 +1 @@
+(import ./flake-compat.nix).defaultNix

tests/flake-compat.nix

@@ -0,0 +1,9 @@
+let
+  lock = builtins.fromJSON (builtins.readFile ./flake.lock);
+  inherit (lock.nodes.flake-compat.locked) owner repo rev narHash;
+  flake-compat = builtins.fetchTarball {
+    url = "https://github.com/${owner}/${repo}/archive/${rev}.tar.gz";
+    sha256 = narHash;
+  };
+in
+import flake-compat { src = ./.; }