From c2db5126234261fb434b2571671771d92f68300a Mon Sep 17 00:00:00 2001
From: Jordan MacDonald <jordan@wastedintelligence.com>
Date: Sat, 21 Sep 2024 12:16:06 -0400
Subject: [PATCH] Fully migrate Nix build to flakes

---
 .envrc      |  2 +-
 default.nix | 38 -----------------------------
 flake.nix   | 70 ++++++++++++++++++++++++++++++++++++++++++++++++++---
 shell.nix   | 14 -----------
 4 files changed, 68 insertions(+), 56 deletions(-)
 delete mode 100644 default.nix
 delete mode 100644 shell.nix

diff --git a/.envrc b/.envrc
index 1d953f4b..3550a30f 100644
--- a/.envrc
+++ b/.envrc
@@ -1 +1 @@
-use nix
+use flake
diff --git a/default.nix b/default.nix
deleted file mode 100644
index 04d4da6c..00000000
--- a/default.nix
+++ /dev/null
@@ -1,38 +0,0 @@
-{ pkgs ? import <nixpkgs> {}, gitSha }:
-  pkgs.rustPlatform.buildRustPackage {
-    pname = "amp";
-    version = "0.7.0";
-    cargoLock.lockFile = ./Cargo.lock;
-
-    # Use source files without version control noise
-    src = pkgs.lib.cleanSource ./.;
-
-    # Packages needed at runtime
-    buildInputs = with pkgs; [ git xorg.libxcb openssl zlib ];
-
-    # Packages needed during the build
-    nativeBuildInputs = with pkgs; [ git ];
-
-    # Make the build/check/install commands explicit so we can
-    # provide the commit SHA for the splash screen
-    buildPhase = ''
-      export BUILD_REVISION=${builtins.substring 0 7 gitSha}
-      echo "BUILD_REVISION=$BUILD_REVISION"
-
-      cargo build --release
-    '';
-
-    checkPhase = ''
-      cargo test
-    '';
-
-    installPhase = ''
-      mkdir -p $out/bin
-      cp target/release/amp $out/bin/
-    '';
-
-    # Amp creates files and directories in $HOME/.config/amp when run.
-    # Since the checkPhase of the build process runs the test suite, we
-    # need a writable location to avoid permission error test failures.
-    HOME="$src";
-  }
diff --git a/flake.nix b/flake.nix
index c8c659f6..4b17a1de 100644
--- a/flake.nix
+++ b/flake.nix
@@ -9,10 +9,74 @@
     let
       supportedSystems = [ "x86_64-linux" ];
       forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
-      pkgsFor = nixpkgs.legacyPackages;
     in {
+      # Define packages for all supported systems
       packages = forAllSystems (system: {
-        default = pkgsFor.${system}.callPackage ./. { gitSha = self.rev; };
+        default = self.buildPackage { inherit system; };
       });
-    };
+
+      # Define dev shells for all supported systems
+      devShells = forAllSystems (system: {
+        default = self.buildShell { inherit system; };
+      });
+
+      # Function to build a dev shell for a given system
+      buildShell = { system }:
+        let pkgs = import nixpkgs { inherit system; };
+        in pkgs.mkShell {
+          buildInputs = with pkgs; [
+            rustc
+            cargo
+            cargo-edit
+            rustfmt
+            rust-analyzer
+            clippy
+          ];
+
+          RUST_BACKTRACE = 1;
+        };
+
+      # Function to build the package for a given system
+      buildPackage = { system }:
+        let pkgs = import nixpkgs { inherit system; };
+        in pkgs.rustPlatform.buildRustPackage {
+          pname = "amp";
+          version = "0.7.0";
+          cargoLock.lockFile = ./Cargo.lock;
+
+          # Use source files without version control noise
+          src = pkgs.lib.cleanSource ./.;
+
+          # Packages needed at runtime
+          buildInputs = with pkgs; [ git xorg.libxcb openssl zlib ];
+
+          # Packages needed during the build
+          nativeBuildInputs = with pkgs; [ git ];
+
+          # Make the build/check/install commands explicit so we can
+          # provide the commit SHA for the splash screen
+          buildPhase = ''
+            export BUILD_REVISION=${builtins.substring 0 7 (
+              if self ? rev then self.rev else ""
+            )}
+            echo "BUILD_REVISION=$BUILD_REVISION"
+
+            cargo build --release
+          '';
+
+          checkPhase = ''
+            cargo test
+          '';
+
+          installPhase = ''
+            mkdir -p $out/bin
+            cp target/release/amp $out/bin/
+          '';
+
+          # Amp creates files and directories in $HOME/.config/amp when run.
+          # Since the checkPhase of the build process runs the test suite, we
+          # need a writable location to avoid permission error test failures.
+          HOME="$src";
+        };
+  };
 }
diff --git a/shell.nix b/shell.nix
deleted file mode 100644
index 38f41210..00000000
--- a/shell.nix
+++ /dev/null
@@ -1,14 +0,0 @@
-{ pkgs ? import <nixpkgs> {}}:
-
-pkgs.mkShell {
-  buildInputs = with pkgs; [
-    rustc
-    cargo
-    cargo-edit
-    rustfmt
-    rust-analyzer
-    clippy
-  ];
-
-  RUST_BACKTRACE = 1;
-}