Replace nixfmt with alejandra

My experience is that alejandra results in significantly smaller diffs compared
to nixfmt.

flake.nix

@@ -1,6 +1,5 @@
 {
-  description =
-    "ripgrep, but also search in PDFs, E-Books, Office documents, zip, tar.gz, etc.";
+  description = "ripgrep, but also search in PDFs, E-Books, Office documents, zip, tar.gz, etc.";
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs";
@@ -34,110 +33,116 @@
     };
   };
 
-  outputs = { self, nixpkgs, crane, flake-utils, rust-overlay, advisory-db
-    , pre-commit-hooks }:
-    flake-utils.lib.eachDefaultSystem (system:
-      let
-        pkgs = import nixpkgs {
-          inherit system;
-          overlays = [ (import rust-overlay) ];
-        };
+  outputs = {
+    self,
+    nixpkgs,
+    crane,
+    flake-utils,
+    rust-overlay,
+    advisory-db,
+    pre-commit-hooks,
+  }:
+    flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = import nixpkgs {
+        inherit system;
+        overlays = [(import rust-overlay)];
+      };
 
-        craneLib = crane.lib.${system};
-        src = pkgs.lib.cleanSourceWith {
-          src = craneLib.path ./.;
-          filter = pkgs.lib.cleanSourceFilter;
-        };
+      craneLib = crane.lib.${system};
+      src = pkgs.lib.cleanSourceWith {
+        src = craneLib.path ./.;
+        filter = pkgs.lib.cleanSourceFilter;
+      };
 
-        nativeBuildInputs = pkgs.lib.optionals pkgs.stdenv.isDarwin [
-          # Additional darwin specific inputs can be set here
-          pkgs.libiconv
-        ];
+      nativeBuildInputs = pkgs.lib.optionals pkgs.stdenv.isDarwin [
+        # Additional darwin specific inputs can be set here
+        pkgs.libiconv
+      ];
 
-        runtimeInputs = with pkgs; [ ffmpeg pandoc poppler_utils ripgrep zip ];
+      runtimeInputs = with pkgs; [ffmpeg pandoc poppler_utils ripgrep zip];
 
-        # Build *just* the cargo dependencies, so we can reuse
-        # all of that work (e.g. via cachix) when running in CI
-        cargoArtifacts =
-          craneLib.buildDepsOnly { inherit src nativeBuildInputs; };
+      # Build *just* the cargo dependencies, so we can reuse
+      # all of that work (e.g. via cachix) when running in CI
+      cargoArtifacts =
+        craneLib.buildDepsOnly {inherit src nativeBuildInputs;};
 
-        # Build the actual crate itself, reusing the dependency
-        # artifacts from above.
-        rgaBinary = craneLib.buildPackage {
-          inherit cargoArtifacts src nativeBuildInputs;
-          buildInputs = runtimeInputs; # needed for tests
-        };
+      # Build the actual crate itself, reusing the dependency
+      # artifacts from above.
+      rgaBinary = craneLib.buildPackage {
+        inherit cargoArtifacts src nativeBuildInputs;
+        buildInputs = runtimeInputs; # needed for tests
+      };
 
-        # Provide a shell script of the Rust binary plus runtime dependencies.
-        rga = pkgs.pkgs.writeShellApplication {
-          name = "rga";
-          text = ''rga "$@"'';
-          runtimeInputs = runtimeInputs ++ [ rgaBinary ];
-        };
+      # Provide a shell script of the Rust binary plus runtime dependencies.
+      rga = pkgs.pkgs.writeShellApplication {
+        name = "rga";
+        text = ''rga "$@"'';
+        runtimeInputs = runtimeInputs ++ [rgaBinary];
+      };
 
-        pre-commit = pre-commit-hooks.lib."${system}".run;
-      in {
-        # `nix flake check`
-        checks = {
-          # Build the crate as part of `nix flake check` for convenience
-          inherit rgaBinary;
-
-          # Run clippy (and deny all warnings) on the crate source,
-          # again, resuing the dependency artifacts from above.
-          #
-          # Note that this is done as a separate derivation so that
-          # we can block the CI if there are issues here, but not
-          # prevent downstream consumers from building our crate by itself.
-          rga-clippy = craneLib.cargoClippy {
-            inherit cargoArtifacts src;
-            cargoClippyExtraArgs = "--all-targets -- --deny warnings";
-          };
+      pre-commit = pre-commit-hooks.lib."${system}".run;
+    in {
+      # `nix flake check`
+      checks = {
+        # Build the crate as part of `nix flake check` for convenience
+        inherit rgaBinary;
+
+        # Run clippy (and deny all warnings) on the crate source,
+        # again, resuing the dependency artifacts from above.
+        #
+        # Note that this is done as a separate derivation so that
+        # we can block the CI if there are issues here, but not
+        # prevent downstream consumers from building our crate by itself.
+        rga-clippy = craneLib.cargoClippy {
+          inherit cargoArtifacts src;
+          cargoClippyExtraArgs = "--all-targets -- --deny warnings";
+        };
 
-          rga-doc = craneLib.cargoDoc { inherit cargoArtifacts src; };
+        rga-doc = craneLib.cargoDoc {inherit cargoArtifacts src;};
 
-          # Check formatting
-          rga-fmt = craneLib.cargoFmt { inherit src; };
+        # Check formatting
+        rga-fmt = craneLib.cargoFmt {inherit src;};
 
-          # Audit dependencies
-          rga-audit = craneLib.cargoAudit { inherit src advisory-db; };
+        # Audit dependencies
+        rga-audit = craneLib.cargoAudit {inherit src advisory-db;};
 
-          # Run tests with cargo-nextest.
-          rga-nextest = craneLib.cargoNextest {
-            inherit cargoArtifacts src nativeBuildInputs;
-            buildInputs = runtimeInputs; # needed for tests
-            partitions = 1;
-            partitionType = "count";
-          };
+        # Run tests with cargo-nextest.
+        rga-nextest = craneLib.cargoNextest {
+          inherit cargoArtifacts src nativeBuildInputs;
+          buildInputs = runtimeInputs; # needed for tests
+          partitions = 1;
+          partitionType = "count";
+        };
 
-          pre-commit = pre-commit {
-            src = ./.;
-            hooks = {
-              nixfmt.enable = true;
-              rustfmt.enable = true;
-              typos = {
-                enable = true;
-                settings = {
-                  exclude = "exampledir/*";
-                };
+        pre-commit = pre-commit {
+          src = ./.;
+          hooks = {
+            alejandra.enable = true;
+            rustfmt.enable = true;
+            typos = {
+              enable = true;
+              settings = {
+                exclude = "exampledir/*";
               };
             };
           };
         };
+      };
 
-        # `nix build`
-        packages = {
-          inherit rgaBinary rga;
-          default = rga; # `nix build`
-        };
+      # `nix build`
+      packages = {
+        inherit rgaBinary rga;
+        default = rga; # `nix build`
+      };
 
-        # `nix run`
-        apps.default = flake-utils.lib.mkApp { drv = rga; };
+      # `nix run`
+      apps.default = flake-utils.lib.mkApp {drv = rga;};
 
-        # `nix develop`
-        devShells.default = craneLib.devShell {
-          inherit (self.checks.${system}.pre-commit) shellHook;
-          inputsFrom = builtins.attrValues self.checks;
-          packages = runtimeInputs ++ nativeBuildInputs;
-        };
-      });
+      # `nix develop`
+      devShells.default = craneLib.devShell {
+        inherit (self.checks.${system}.pre-commit) shellHook;
+        inputsFrom = builtins.attrValues self.checks;
+        packages = runtimeInputs ++ nativeBuildInputs;
+      };
+    });
 }