add hook installation test

.github/workflows/ci.yaml

@@ -30,5 +30,5 @@ jobs:
         name: pre-commit-hooks
         signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
     - run: rm -rf /opt&
-    - run: nix flake check --show-trace
+    - run: nix flake check -L --show-trace
     - run: nix eval .#lib.x86_64-linux.run --show-trace

README.md

@@ -92,7 +92,7 @@ nix develop
           ormolu.enable = true;
           ormolu.package = pkgs.haskellPackages.ormolu;
           ormolu.settings.defaultExtensions = [ "lhs" "hs" ];
-          
+
           # some hooks have more than one package, like clippy:
           clippy.enable = true;
           clippy.packageOverrides.cargo = pkgs.cargo;
@@ -109,7 +109,7 @@ nix develop
 3. Integrate hooks to prepare environment as part of `shell.nix`:
 
    ```nix
-    let 
+    let
       pre-commit = import ./default.nix;
     in (import <nixpkgs> {}).mkShell {
       shellHook = ''
@@ -318,7 +318,7 @@ clang-format = {
 };
 ```
 
-Otherwise, the default internal list is used which includes everything that 
+Otherwise, the default internal list is used which includes everything that
 clang-format supports.
 
 ## Git
@@ -373,6 +373,9 @@ Example configuration:
          # Set this to false to not pass the changed files
          # to the command (default: true):
          pass_filenames = false;
+
+         # Which git hooks the command should run for (default: [ "pre-commit" ]):
+         stages = ["pre-push"];
        };
      };
    };

flake.nix

@@ -35,7 +35,7 @@
     }
     // flake-utils.lib.eachSystem defaultSystems (system:
       let
-        exposed = import ./nix { nixpkgs = nixpkgs; inherit system; gitignore-nix-src = gitignore; isFlakes = true; };
+        exposed = import ./nix { inherit nixpkgs system; gitignore-nix-src = gitignore; isFlakes = true; };
         exposed-stable = import ./nix { nixpkgs = nixpkgs-stable; inherit system; gitignore-nix-src = gitignore; isFlakes = true; };
       in
       {

modules/hook.nix

@@ -155,7 +155,7 @@ in
     };
 
     stages = mkOption {
-      type = types.listOf types.str;
+      type = (import ./supported-hooks.nix { inherit lib; }).supportedHooksType;
       description = lib.mdDoc ''
         Confines the hook to run at a particular stage.
       '';

modules/pre-commit.nix

@@ -10,12 +10,15 @@ let
     mkIf
     mkOption
     types
+    remove
     ;
 
   inherit (pkgs) runCommand writeText git;
 
   cfg = config;
-  install_stages = lib.unique (cfg.default_stages ++ (builtins.concatLists (lib.mapAttrsToList (_: h: h.stages) enabledHooks)));
+  install_stages = lib.unique (builtins.concatLists (lib.mapAttrsToList (_: h: h.stages) enabledHooks));
+
+  supportedHooksLib = import ./supported-hooks.nix { inherit lib; };
 
   hookType = types.submodule {
     imports = [
@@ -175,7 +178,7 @@ in
               The predefined hooks are:
 
               ${
-                lib.concatStringsSep
+                concatStringsSep
                   "\n"
                   (lib.mapAttrsToList
                     (hookName: hookConf:
@@ -253,14 +256,14 @@ in
 
       default_stages =
         mkOption {
-          type = types.listOf types.str;
+          type = supportedHooksLib.supportedHooksType;
           description = lib.mdDoc
             ''
               A configuration wide option for the stages property.
               Installs hooks to the defined stages.
               See [https://pre-commit.com/#confining-hooks-to-run-at-certain-stages](https://pre-commit.com/#confining-hooks-to-run-at-certain-stages).
             '';
-          default = [ "commit" ];
+          default = [ "pre-commit" ];
         };
 
       rawConfig =
@@ -332,12 +335,11 @@ in
 
             # These update procedures compare before they write, to avoid
             # filesystem churn. This improves performance with watch tools like lorri
-            # and prevents installation loops by via lorri.
+            # and prevents installation loops by lorri.
 
             if ! readlink "''${GIT_WC}/.pre-commit-config.yaml" >/dev/null \
               || [[ $(readlink "''${GIT_WC}/.pre-commit-config.yaml") != ${configFile} ]]; then
               echo 1>&2 "pre-commit-hooks.nix: updating $PWD repo"
-
               [ -L .pre-commit-config.yaml ] && unlink .pre-commit-config.yaml
 
               if [ -e "''${GIT_WC}/.pre-commit-config.yaml" ]; then
@@ -349,24 +351,23 @@ in
               else
                 ln -fs ${configFile} "''${GIT_WC}/.pre-commit-config.yaml"
                 # Remove any previously installed hooks (since pre-commit itself has no convergent design)
-                hooks="pre-commit pre-merge-commit pre-push prepare-commit-msg commit-msg post-checkout post-commit"
+                hooks="${concatStringsSep " " (remove "manual" supportedHooksLib.supportedHooks )}"
                 for hook in $hooks; do
                   pre-commit uninstall -t $hook
                 done
                 ${git}/bin/git config --local core.hooksPath ""
                 # Add hooks for configured stages (only) ...
                 if [ ! -z "${concatStringsSep " " install_stages}" ]; then
                   for stage in ${concatStringsSep " " install_stages}; do
-                    if [[ "$stage" == "manual" ]]; then
-                      continue
-                    fi
                     case $stage in
+                      manual)
+                        ;;
                       # if you amend these switches please also review $hooks above
                       commit | merge-commit | push)
                         stage="pre-"$stage
                         pre-commit install -t $stage
                         ;;
-                      prepare-commit-msg | commit-msg | post-checkout | post-commit)
+                      ${concatStringsSep "|" supportedHooksLib.supportedHooks})
                         pre-commit install -t $stage
                         ;;
                       *)

modules/supported-hooks.nix

@@ -0,0 +1,30 @@
+{ lib }:
+let inherit (lib) types;
+  # according to https://pre-commit.com/#supported-git-hooks
+  supportedHooks = [
+    "commit-msg"
+    "post-checkout"
+    "post-commit"
+    "post-merge"
+    "post-rewrite"
+    "pre-commit"
+    "pre-merge-commit"
+    "pre-push"
+    "pre-rebase"
+    "prepare-commit-msg"
+    "manual"
+  ];
+in
+{
+  inherit supportedHooks;
+
+  supportedHooksType =
+    let
+      deprecatedHooks = [
+        "commit"
+        "push"
+        "merge-commit"
+      ];
+    in
+    types.listOf (types.enum (supportedHooks ++ deprecatedHooks));
+}

nix/default.nix

@@ -27,6 +27,7 @@ let
             typos.enable = true;
           };
         };
+        installation-test = pkgs.callPackage ./installation-test.nix { inherit run; };
         all-tools-eval =
           let
             config = lib.evalModules {

nix/installation-test.nix

@@ -0,0 +1,99 @@
+# Test that checks whether the correct hooks are created in the hooks folder.
+{ git, perl, coreutils, runCommand, run, lib, mktemp }:
+let
+  tests = {
+    basic-test = {
+      expectedHooks = [ "pre-commit" ];
+      conf.hooks.shellcheck.enable = true;
+    };
+
+    multiple-hooks-test = {
+      expectedHooks = [ "commit-msg" "pre-commit" ];
+      conf.hooks = {
+        shellcheck.enable = true;
+        nixpkgs-fmt = {
+          enable = true;
+          stages = [ "commit-msg" ];
+        };
+      };
+    };
+
+    non-default-stage-test = {
+      expectedHooks = [ "commit-msg" ];
+      conf.hooks.nixpkgs-fmt = {
+        enable = true;
+        stages = [ "commit-msg" ];
+      };
+    };
+
+    default-stage-test = {
+      expectedHooks = [ "commit-msg" ];
+      conf = {
+        default_stages = [ "commit-msg" ];
+        hooks.nixpkgs-fmt.enable = true;
+      };
+    };
+
+    manual-default-stage-test = {
+      expectedHooks = [ ];
+      conf = {
+        default_stages = [ "manual" ];
+        hooks.nixpkgs-fmt.enable = true;
+      };
+    };
+
+    multiple-default-stages-test = {
+      expectedHooks = [ "pre-push" ];
+      conf = {
+        default_stages = [ "manual" "pre-push" ];
+        hooks.nixpkgs-fmt.enable = true;
+      };
+    };
+
+    deprecated-gets-prefixed-test = {
+      expectedHooks = [ "pre-push" ];
+      conf.hooks.nixpkgs-fmt = {
+        enable = true;
+        stages = [ "push" ];
+      };
+    };
+  };
+
+  executeTest = lib.mapAttrsToList
+    (name: test:
+      let runDerivation = run ({ src = null; } // test.conf);
+      in ''
+        rm -f ~/.git/hooks/*
+        ${runDerivation.shellHook}
+        actualHooks=(`find ~/.git/hooks -type f -printf "%f "`)
+        read -a expectedHooks <<< "${builtins.toString test.expectedHooks}"
+        if ! assertArraysEqual actualHooks expectedHooks; then
+          echo "${name} failed: Expected hooks '${builtins.toString test.expectedHooks}' but found '$actualHooks'."
+          return 1
+        fi
+      '')
+    tests;
+in
+runCommand "installation-test" { nativeBuildInputs = [ git perl coreutils mktemp ]; } ''
+  set -eoux
+
+  HOME=$(mktemp -d)
+  cd $HOME
+  git init
+
+  assertArraysEqual() {
+    local -n _array_one=$1
+    local -n _array_two=$2
+    diffArray=(`echo ''${_array_one[@]} ''${_array_two[@]} | tr ' ' '\n' | sort | uniq -u`)
+    if [ ''${#diffArray[@]} -eq 0 ]
+    then
+      return 0
+    else
+      return 1
+    fi
+  }
+
+  ${lib.concatStrings executeTest}
+
+  echo "success" > $out
+''