Feature: add nix support (#2)

* Initial commit

* Improve flake.nix

* Remove hello-world print in flake.nix

* Improve flake

* Add default package

.envrc

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+# Watch & reload direnv on change
+watch_file devshell.toml
+
+if [[ $(type -t use_flake) != function ]]; then
+  echo "ERROR: use_flake function missing."
+  echo "Please update direnv to v2.30.0 or later."
+  exit 1
+fi
+
+use flake

.gitignore

@@ -33,3 +33,4 @@
 
 /build/
 /bazel-*
+/.direnv

WORKSPACE

@@ -0,0 +1 @@
+workspace(name = "cosmos-cli")

devshell.toml

@@ -0,0 +1,7 @@
+[env]
+FOO = "barh"
+
+[devshell]
+packages = [
+    "bazel",
+]

flake.nix

@@ -0,0 +1,48 @@
+{
+  description = "Cosmos CLI";
+
+  inputs = {
+    nixpkgs.url = "https://releases.nixos.org/nixos/23.05/nixos-23.05.861.d3bb401dcfc/nixexprs.tar.xz";
+    flake-utils.url = "git+https://github.com/numtide/flake-utils?ref=main";
+  };
+
+  outputs = { self, nixpkgs, flake-utils, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+        };
+        nativeBuildInputs = with pkgs;
+        [
+          bazel_6
+          bazel-buildtools
+        ];
+        cosmos = pkgs.stdenv.mkDerivation {
+          name = "cosmos";
+          version = "0.0.1";
+          src = self;
+          nativeBuildInputs = nativeBuildInputs;
+          buildPhase = ''
+            bazel build //src:hello-world;
+          '';
+
+          installPhase = ''
+            mkdir -p $out/bin;
+            cp -r bazel-bin/src/hello-world $out/bin;
+          '';
+        };
+      in rec
+      {
+        defaultPackage = cosmos;
+        devShells.default = pkgs.mkShell {
+          nativeBuildInputs = nativeBuildInputs ++ [
+            cosmos
+          ];
+        };
+
+        # default = pkgs.devshell.mkShell {
+        #   imports = [ (pkgs.devshell.importTOML ./devshell.toml) ];
+        # };
+
+      });
+}

result

@@ -0,0 +1 @@
+/nix/store/922i6v34m2r5r8q2qhb8gqflav3zry87-cosmos

shell.nix

@@ -0,0 +1 @@
+(builtins.getFlake ("git+file://" + toString ./.)).devShells.${builtins.currentSystem}.default

tools/nix.sh

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+
+nix flake lock --update-input nixpkgs
+nix flake update

tools/setup.sh

@@ -4,6 +4,8 @@
 
 brew install bazelisk
 
+# sh <(curl -L https://nixos.org/nix/install)
+
 # for linting
 brew install clang-format
 brew install buildifier