Clean up Nix Flake and packaging (#24)

* refactor(nix): split package.nix from flake.nix

* chore(nix): split checks; add more

* ci: run all nix checks

* ci: build in debug mode

* chore(nix): use versionCheckHook

this makes sure the version test is always run, and on the right package

* chore(nix): nix-filter -> lib.fileset

* feat(nix): support stable nix

* ci: fix clippy check

1 files changed, 64 insertions, 0 deletions

diff --git a/nix/package.nix b/nix/package.nix
new file mode 100644
index 0000000..cc60573
--- /dev/null
+++ b/nix/package.nix
@@ -0,0 +1,64 @@
+{
+  lib,
+  installShellFiles,
+  makeBinaryWrapper,
+  nix,
+  rustPlatform,
+  versionCheckHook,
+}:
+
+let
+  fs = lib.fileset;
+in
+rustPlatform.buildRustPackage rec {
+  pname = "nix-forecast";
+  inherit (passthru.cargoTOML.package) version;
+
+  src = fs.toSource {
+    root = ../.;
+    fileset = fs.intersection (fs.gitTracked ../.) (
+      fs.unions [
+        ../Cargo.lock
+        ../Cargo.toml
+        ../build.rs
+        ../src
+      ]
+    );
+  };
+
+  cargoLock.lockFile = ../Cargo.lock;
+
+  nativeBuildInputs = [
+    installShellFiles
+    makeBinaryWrapper
+  ];
+
+  doInstallCheck = true;
+  nativeInstallCheckInputs = [ versionCheckHook ];
+
+  postInstall = ''
+    wrapProgram $out/bin/nix-forecast --suffix PATH : ${lib.makeBinPath [ nix ]}
+
+    installShellCompletion --cmd nix-forecast \
+      --bash completions/nix-forecast.bash \
+    	--fish completions/nix-forecast.fish \
+    	--zsh completions/_nix-forecast
+  '';
+
+  env = {
+    COMPLETION_DIR = "completions";
+  };
+
+  passthru = {
+    cargoTOML = lib.importTOML ../Cargo.toml;
+  };
+
+  meta = {
+    description = "Check the forecast for today's Nix builds";
+    homepage = "https://github.com/getchoo/nix-forecast";
+    changelog = "https://github.com/getchoo/nix-forecast/releases/tag/${version}";
+    license = lib.licenses.mpl20;
+    maintainers = with lib.maintainers; [ getchoo ];
+    mainProgram = "nix-forecast";
+  };
+}