From 87ec4517bc3f6760a81d28c79e25c386209819ce Mon Sep 17 00:00:00 2001
From: Matthieu Coudron <mcoudron@hotmail.com>
Date: Wed, 15 Dec 2021 19:00:41 +0100
Subject: [PATCH] build: add flake.nix

run `nix develop` to get a development environment
---
 flake.lock | 195 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 flake.nix  |  59 ++++++++++++++++
 shell.nix  |   9 +++
 3 files changed, 263 insertions(+)
 create mode 100644 flake.lock
 create mode 100644 flake.nix
 create mode 100644 shell.nix

diff --git a/flake.lock b/flake.lock
new file mode 100644
index 000000000..aad1b2596
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,195 @@
+{
+  "nodes": {
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1627913399,
+        "narHash": "sha256-hY8g6H2KFL8ownSiFeMOjwPC8P0ueXpCVEbxgda3pko=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "12c64ca55c1014cdc1b16ed5a804aa8576601ff2",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
+    "flake-compat_2": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1627913399,
+        "narHash": "sha256-hY8g6H2KFL8ownSiFeMOjwPC8P0ueXpCVEbxgda3pko=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "12c64ca55c1014cdc1b16ed5a804aa8576601ff2",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1638122382,
+        "narHash": "sha256-sQzZzAbvKEqN9s0bzWuYmRaA03v40gaJ4+iL1LXjaeI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "74f7e4319258e287b0f9cb95426c9853b282730b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
+      "locked": {
+        "lastModified": 1629481132,
+        "narHash": "sha256-JHgasjPR0/J1J3DRm4KxM4zTyAj4IOJY8vIl75v/kPI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "997f7efcb746a9c140ce1f13c72263189225f482",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_3": {
+      "locked": {
+        "lastModified": 1638122382,
+        "narHash": "sha256-sQzZzAbvKEqN9s0bzWuYmRaA03v40gaJ4+iL1LXjaeI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "74f7e4319258e287b0f9cb95426c9853b282730b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "gitignore": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1611672876,
+        "narHash": "sha256-qHu3uZ/o9jBHiA3MEKHJ06k7w4heOhA+4HCSIvflRxo=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "211907489e9f198594c0eb0ca9256a1949c9d412",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
+    "hls": {
+      "inputs": {
+        "flake-compat": "flake-compat_2",
+        "flake-utils": "flake-utils_2",
+        "gitignore": "gitignore",
+        "nixpkgs": "nixpkgs",
+        "pre-commit-hooks": "pre-commit-hooks"
+      },
+      "locked": {
+        "lastModified": 1639549452,
+        "narHash": "sha256-/LkwuvKeK9e1kCqxXTgWMN54XJ0J2jae36aKyxfw69E=",
+        "owner": "haskell",
+        "repo": "haskell-language-server",
+        "rev": "854d2c5a1aa3095c93e3f38ef3731be89b4ab09a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "haskell",
+        "repo": "haskell-language-server",
+        "rev": "854d2c5a1aa3095c93e3f38ef3731be89b4ab09a",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1639357775,
+        "narHash": "sha256-mJJFCPqZi1ZO3CvgEfN2nFAYv4uAJSRnTKzLFi61+WA=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "c473cc8714710179df205b153f4e9fa007107ff9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1639566195,
+        "narHash": "sha256-ZnTBGSV6bTwopdDibmsBaAkedmTZC/rOgwQzOGcOD+s=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "3c52ea8c9216a0d5b7a7b4d74a9d2e858b06df5c",
+        "type": "github"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1639525045,
+        "narHash": "sha256-z4GXFNzO+5V4CAUm2DDMAryLOWUKEbQif2ifvv1Ypg4=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "a2e281f5770247855b85d70c43454ba5bff34613",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-utils": "flake-utils_3",
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1624971177,
+        "narHash": "sha256-Amf/nBj1E77RmbSSmV+hg6YOpR+rddCbbVgo5C7BS0I=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "397f0713d007250a2c7a745e555fa16c5dc8cadb",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-compat": "flake-compat",
+        "flake-utils": "flake-utils",
+        "hls": "hls",
+        "nixpkgs": "nixpkgs_3"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 000000000..15df1ab23
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,59 @@
+{
+  description = "My haskell library";
+
+  nixConfig = {
+    extra-substituters = [
+      "https://haskell-language-server.cachix.org"
+    ];
+    extra-trusted-public-keys = [
+      "haskell-language-server.cachix.org-1:juFfHrwkOxqIOZShtC4YC1uT1bBcq2RSvC7OMKx0Nz8="
+    ];
+  };
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    hls.url = "github:haskell/haskell-language-server/854d2c5a1aa3095c93e3f38ef3731be89b4ab09a";
+
+    flake-compat = {
+      url = "github:edolstra/flake-compat";
+      flake = false;
+    };
+  };
+
+  outputs = { self, nixpkgs, flake-utils, hls, ... }:
+    flake-utils.lib.eachSystem ["x86_64-linux"] (system: let
+
+      pkgs = nixpkgs.legacyPackages.${system};
+
+      ghc8107 = pkgs.haskell.packages."ghc8107";
+
+      # modifier used in haskellPackages.developPackage
+      myModifier = hsPkgs: drv: let
+        compilerVersion = pkgs.lib.replaceStrings [ "." ] [ "" ] hsPkgs.ghc.version;
+      in
+        pkgs.haskell.lib.addBuildTools drv ([
+          hsPkgs.cabal-install
+          hls.packages.${system}."haskell-language-server-${compilerVersion}"
+          pkgs.openssl.dev
+          pkgs.zlib
+        ]);
+
+      mkPackage = hsPkgs:
+          hsPkgs.developPackage {
+            root =  pkgs.lib.cleanSource ./. ;
+            name =  "cabal2nix";
+            returnShellEnv = false;
+            withHoogle = true;
+            modifier = myModifier hsPkgs;
+          };
+
+    in {
+      packages = {
+        cabal2nix = self.packages.${system}.cabal2nix-8107;
+        cabal2nix-8107 = mkPackage ghc8107;
+      };
+
+      defaultPackage = self.packages.${system}.cabal2nix;
+  });
+}
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 000000000..b769069b9
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,9 @@
+(import (
+  let
+    lock = builtins.fromJSON (builtins.readFile ./flake.lock);
+  in fetchTarball {
+    url = "https://github.com/edolstra/flake-compat/archive/${lock.nodes.flake-compat.locked.rev}.tar.gz";
+    sha256 = lock.nodes.flake-compat.locked.narHash; }
+) {
+  src =  ./.;
+}).shellNix