From a72ac37698ffc3d0a5aa63deb81f4223a09f1bc7 Mon Sep 17 00:00:00 2001
From: Tomasz Zurkowski <tomasz.zurkowski@gmail.com>
Date: Wed, 8 Jan 2025 20:48:19 +0100
Subject: [PATCH] Add rust-toolchain and nix flake (#20)

rust-toolchain will allow us to ensure that everyone developing on the
repository is using the same version of rust.

Nix flake will provide out-of-the-box development environment for nix
users with the right rust version.
---
 .gitignore          |  7 ++++
 flake.lock          | 82 +++++++++++++++++++++++++++++++++++++++++++++
 flake.nix           | 60 +++++++++++++++++++++++++++++++++
 rust-toolchain.toml |  1 +
 4 files changed, 150 insertions(+)
 create mode 100644 flake.lock
 create mode 100644 flake.nix

diff --git a/.gitignore b/.gitignore
index 39ee975..e77cc4e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,10 @@
 
 .vscode/*
 .DS_Store
+
+# Allow everyone to customize .envrc
+/.envrc
+# Output / cache from direnv
+/.direnv
+# Output from nix
+/result
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..80ebcfb
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,82 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1736166416,
+        "narHash": "sha256-U47xeACNBpkSO6IcCm0XvahsVXpJXzjPIQG7TZlOToU=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "b30f97d8c32d804d2d832ee837d0f1ca0695faa5",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1736216977,
+        "narHash": "sha256-EMueGrzBpryM8mgOyoyJ7DdNRRk09ug1ggcLLp0WrCQ=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "bbe7e4e7a70d235db4bbdcabbf8a2f6671881dd7",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..fea17fc
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,60 @@
+{
+  # This is a Nix Flake that defines development environment for this project.
+  #
+  # Using Nix is NOT required to develop this project.
+  #
+  # Nix provides a declariative way to define reproducible development environment
+  # and aims to remove the issue of "works on my machine".
+  # 
+  # If you use Nix, you can install and activate all dependencies required to
+  # develop on this project with:
+  #
+  # $ nix develop
+  #
+  # If in addition you have `direnv` installed, you can create `.envrc` file with
+  # `use flake` content, so that development environment activates automatically
+  # when the project root directory is entered. 
+  # 
+  # More information:
+  # - Nix: https://nixos.org
+  # - Nix flakes:  https://wiki.nixos.org/wiki/Flakes
+  # - Direnv: https://direnv.net
+  description = "The New Nushell Parser";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    rust-overlay = {
+      url = "github:oxalica/rust-overlay";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs =
+    {
+      nixpkgs,
+      rust-overlay,
+      flake-utils,
+      ...
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        overlays = [ (import rust-overlay) ];
+        pkgs = import nixpkgs { inherit system overlays; };
+        rustToolchain = pkgs.rust-bin.fromRustupToolchainFile ./rust-toolchain.toml;
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          nativeBuildInputs = [
+            (rustToolchain.override {
+              extensions = [
+                "rust-src"
+                "rust-analyzer"
+              ];
+            })
+          ];
+        };
+      }
+    );
+}
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index aa2b18f..e2fad99 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -3,4 +3,5 @@
 # The default profile includes rustc, rust-std, cargo, rust-docs, rustfmt and clippy.
 # https://rust-lang.github.io/rustup/concepts/profiles.html
 profile = "default"
+# When updating, it might be necessary to run `nix flake update`.
 channel = "1.81.0"