Add nix-tidy-fix ci check

dev/treefmt.nix

@@ -7,10 +7,10 @@
   programs.yamlfmt.enable = true;
 
   programs.clang-format.enable = true;
+  programs.clang-format.package = pkgs.llvmPackages_latest.clang-tools;
 
   programs.deadnix.enable = true;
   programs.nixfmt.enable = true;
-  programs.nixfmt.package = pkgs.nixfmt-rfc-style;
   programs.ruff.format = true;
   programs.ruff.check = true;
 }

flake.nix

@@ -63,6 +63,36 @@
 
           checks = builtins.removeAttrs self'.packages [ "default" ] // {
             shell = self'.devShells.default;
+            clang-tidy-fix = self'.packages.nix-eval-jobs.overrideAttrs (old: {
+              nativeBuildInputs = old.nativeBuildInputs ++ [
+                pkgs.git
+                (lib.hiPrio pkgs.llvmPackages_latest.clang-tools)
+              ];
+              buildPhase = ''
+                export HOME=$TMPDIR
+                cat > $HOME/.gitconfig <<EOF
+                [user]
+                  name = Nix
+                  email = nix@localhost
+                [init]
+                  defaultBranch = main
+                EOF
+                pushd ..
+                git init
+                git add .
+                git commit -m init --quiet
+                popd
+                ninja clang-tidy-fix
+                git status
+                if ! git --no-pager diff --exit-code; then
+                  echo "clang-tidy-fix failed, please run `ninja clang-tidy-fix` and commit the changes"
+                  exit 1
+                fi
+              '';
+              installPhase = ''
+                touch $out
+              '';
+            });
           };
         };
     };

shell.nix

@@ -26,7 +26,7 @@ in
   inherit (nix-eval-jobs) buildInputs;
   nativeBuildInputs = nix-eval-jobs.nativeBuildInputs ++ [
     (pkgs.python3.withPackages (ps: [ ps.pytest ]))
-    (lib.hiPrio pkgs.clang-tools)
+    (lib.hiPrio pkgs.llvmPackages_latest.clang-tools)
   ];
 
   shellHook = lib.optionalString stdenv.isLinux ''

src/drv.cc

@@ -34,9 +34,10 @@
 
 namespace {
 
-auto queryCacheStatus(nix::Store &store,
-                      std::map<std::string, std::optional<std::string>>
-                          &outputs) -> Drv::CacheStatus {
+auto queryCacheStatus(
+    nix::Store &store,
+    std::map<std::string, std::optional<std::string>> &outputs)
+    -> Drv::CacheStatus {
     uint64_t downloadSize = 0;
     uint64_t narSize = 0;
     nix::StorePathSet willBuild;

src/nix-eval-jobs.cc

@@ -61,7 +61,6 @@
 
 namespace {
 MyArgs myArgs; // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
-}
 
 using Processor = std::function<void(MyArgs &myArgs, nix::AutoCloseFD &to,
                                      nix::AutoCloseFD &from)>;
@@ -374,6 +373,7 @@ void collector(nix::Sync<State> &state_, std::condition_variable &wakeup) {
         wakeup.notify_all();
     }
 }
+} // namespace
 
 auto main(int argc, char **argv) -> int {
 
@@ -429,7 +429,7 @@ auto main(int argc, char **argv) -> int {
         }
 
         if (myArgs.gcRootsDir.empty()) {
-            nix::Path tmpDir = nix::createTempDir();
+            const nix::Path tmpDir = nix::createTempDir();
             gcRootsDir.emplace(tmpDir, true);
             myArgs.gcRootsDir = tmpDir;
         } else {
@@ -445,6 +445,7 @@ auto main(int argc, char **argv) -> int {
         /* Start a collector thread per worker process. */
         std::vector<Thread> threads;
         std::condition_variable wakeup;
+        threads.reserve(myArgs.nrWorkers);
         for (size_t i = 0; i < myArgs.nrWorkers; i++) {
             threads.emplace_back(
                 [&state_, &wakeup] { collector(state_, wakeup); });

src/strings-portable.cc

@@ -1,4 +1,5 @@
 #include <cstring>
+#include "strings-portable.hh"
 
 #ifdef __APPLE__
 // for sys_siglist and sys_errlist

src/worker.cc

@@ -256,7 +256,7 @@ void worker(
                 reply["attrs"] = nlohmann::json::array();
             }
         } catch (nix::EvalError &e) {
-            auto err = e.info();
+            const auto &err = e.info();
             std::ostringstream oss;
             nix::showErrorInfo(oss, err, nix::loggerSettings.showTrace.get());
             auto msg = oss.str();