Fix Nix build & direnv config

.envrc

@@ -1,11 +1,11 @@
-# If nix is installed hook into it.
-if [ $(which nix) ]
-then
+#!/usr/bin/env bash
+
+if has nix; then
+    # If nix is installed hook into it.
     use flake
 fi
 
 # If nu is the current shell use toolkit.nu
-if [ $(echo $SHELL) == $(which nu) ]
-then    
+if [ $(echo $SHELL) == $(which nu) ]; then
     nu -e "use toolkit.nu"
 fi

flake.nix

@@ -5,37 +5,126 @@
     nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
     flake-utils.url = "github:numtide/flake-utils";
 
-    rust-overlay.url = "github:oxalica/rust-overlay";
+    rust-overlay = {
+      url = "github:oxalica/rust-overlay";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+
+    treefmt-nix = {
+      url = "github:numtide/treefmt-nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
-  outputs = { self, nixpkgs, rust-overlay, flake-utils, ... }:
-    flake-utils.lib.eachDefaultSystem (system:
+  outputs =
+    { self, ... }@inputs:
+    inputs.flake-utils.lib.eachDefaultSystem (
+      system:
       let
-        overlays = [ (import rust-overlay) ];
-        pkgs = import nixpkgs {
+        overlays = [ (import inputs.rust-overlay) ];
+        pkgs = import inputs.nixpkgs {
           inherit system overlays;
         };
+        integrationTestPatch = pkgs.writeTextFile {
+          name = "integration-tests-nix-fix.patch";
+          text =
+            # patch
+            ''
+              diff --git a/tests/main.rs b/tests/main.rs
+              index c19811d..33c3829 100644
+              --- a/tests/main.rs
+              +++ b/tests/main.rs
+              @@ -15,7 +15,7 @@ fn failure_with_invalid_config() {
+                   let config_file = dir.path().join("nufmt.nuon");
+                   fs::write(&config_file, r#"{unknown: 1}"#).unwrap();
+
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("--config")
+                       .arg(config_file.to_str().unwrap())
+                       .arg(dir.path().to_str().unwrap())
+              @@ -29,7 +29,7 @@ fn failure_with_invalid_config() {
+
+               #[test]
+               fn failure_with_invalid_config_file() {
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("--config")
+                       .arg("path/that/does/not/exist/nufmt.nuon")
+                       .output()
+              @@ -42,7 +42,7 @@ fn failure_with_invalid_config_file() {
+
+               #[test]
+               fn failure_with_invalid_file_to_format() {
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("path/that/does/not/exist/a.nu")
+                       .output()
+                       .unwrap();
+              @@ -56,7 +56,7 @@ fn failure_with_invalid_file_to_format() {
+               fn warning_when_no_files_are_detected() {
+                   let dir = tempdir().unwrap();
+
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("--dry-run")
+                       .arg(dir.path().to_str().unwrap())
+                       .output()
+              @@ -75,7 +75,7 @@ fn warning_is_displayed_when_no_files_are_detected_with_excluded_files() {
+                   fs::write(&config_file, r#"{exclude: ["a*"]}"#).unwrap();
+                   fs::write(&file_a, INVALID).unwrap();
+
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("--config")
+                       .arg(config_file.to_str().unwrap())
+                       .arg("--dry-run")
+              @@ -98,7 +98,7 @@ fn files_are_reformatted() {
+                   fs::write(&file_a, INVALID).unwrap();
+                   fs::write(&file_b, INVALID).unwrap();
+
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("--config")
+                       .arg(config_file.to_str().unwrap())
+                       .arg(dir.path().to_str().unwrap())
+              @@ -122,7 +122,7 @@ fn files_are_checked() {
+                   fs::write(&file_a, INVALID).unwrap();
+                   fs::write(&file_b, INVALID).unwrap();
+
+              -    let output = Command::new("target/debug/nufmt")
+              +    let output = Command::new("target/@target_triple@/release/nufmt")
+                       .arg("--config")
+                       .arg(config_file.to_str().unwrap())
+                       .arg("--dry-run")
+            '';
+        };
       in
       {
         devShells.default = pkgs.mkShell {
-          nativeBuildInputs = with pkgs; [
-            rust-bin.stable.latest.default
-            rust-analyzer
-
+          inputsFrom = [ self.packages.${system}.default ];
+          packages = with pkgs; [
             nushell
-          ];
 
-          buildInputs = with pkgs; [ ];
+            # Not included in the package dependencies, but used for development
+            rust-analyzer
+          ];
         };
 
-        packages.default = pkgs.rustPlatform.buildRustPackage rec {
+        packages.default = self.packages.${system}.nufmt;
+        packages.nufmt = pkgs.rustPlatform.buildRustPackage {
           name = "nufmt";
-
           src = ./.;
+          patches = [
+            (pkgs.replaceVars "${integrationTestPatch}" {
+              target_triple = pkgs.stdenv.hostPlatform.rust.rustcTarget;
+            })
+          ];
+          cargoLock.lockFile = ./Cargo.lock;
+        };
 
-          cargoLock = {
-            lockFile = ./Cargo.lock;
-          };
+        formatter = inputs.treefmt-nix.lib.mkWrapper pkgs {
+          programs.nixfmt.enable = true;
         };
       }
     );