Add GitRepo::Options type

src/libfetchers-tests/git-utils.cc

@@ -48,7 +48,7 @@ class GitUtilsTest : public ::testing::Test
 
     ref<GitRepo> openRepo()
     {
-        return GitRepo::openRepo(tmpDir, true, false);
+        return GitRepo::openRepo(tmpDir, {.create = true});
     }
 
     std::string getRepoName() const

src/libfetchers/git-utils.cc

@@ -203,16 +203,19 @@ static git_packbuilder_progress PACKBUILDER_PROGRESS_CHECK_INTERRUPT = &packBuil
 
 } // extern "C"
 
-static void initRepoAtomically(std::filesystem::path & path, bool bare)
+static void initRepoAtomically(std::filesystem::path & path, GitRepo::Options options)
 {
     if (pathExists(path.string()))
         return;
 
+    if (!options.create)
+        throw Error("Git repository %s does not exist.", path);
+
     std::filesystem::path tmpDir = createTempDir(path.parent_path());
     AutoDelete delTmpDir(tmpDir, true);
     Repository tmpRepo;
 
-    if (git_repository_init(Setter(tmpRepo), tmpDir.string().c_str(), bare))
+    if (git_repository_init(Setter(tmpRepo), tmpDir.string().c_str(), options.bare))
         throw Error("creating Git repository %s: %s", path, git_error_last()->message);
     try {
         std::filesystem::rename(tmpDir, path);
@@ -234,7 +237,7 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
     /** Location of the repository on disk. */
     std::filesystem::path path;
 
-    bool bare;
+    Options options;
 
     /**
      * libgit2 repository. Note that new objects are not written to disk,
@@ -255,18 +258,18 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
      */
     git_odb_backend * packBackend = nullptr;
 
-    GitRepoImpl(std::filesystem::path _path, bool create, bool bare, bool packfilesOnly = false)
+    GitRepoImpl(std::filesystem::path _path, Options _options)
         : path(std::move(_path))
-        , bare(bare)
+        , options(_options)
     {
         initLibGit2();
 
-        initRepoAtomically(path, bare);
+        initRepoAtomically(path, options);
         if (git_repository_open(Setter(repo), path.string().c_str()))
             throw Error("opening Git repository %s: %s", path, git_error_last()->message);
 
         ObjectDb odb;
-        if (packfilesOnly) {
+        if (options.packfilesOnly) {
             /* Create a fresh object database because by default the repo also
                loose object backends. We are not using any of those for the
                tarball cache, but libgit2 still does a bunch of unnecessary
@@ -295,7 +298,7 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
         if (git_odb_add_backend(odb.get(), mempackBackend, 999))
             throw Error("adding mempack backend to Git object database: %s", git_error_last()->message);
 
-        if (packfilesOnly) {
+        if (options.packfilesOnly) {
             if (git_repository_set_odb(repo.get(), odb.get()))
                 throw Error("setting Git object database: %s", git_error_last()->message);
         }
@@ -366,7 +369,7 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
     {
         // TODO: as an optimization, it would be nice to include `this` in the pool.
         return Pool<GitRepoImpl>(std::numeric_limits<size_t>::max(), [this]() -> ref<GitRepoImpl> {
-            return make_ref<GitRepoImpl>(path, false, bare);
+            return make_ref<GitRepoImpl>(path, options);
         });
     }
 
@@ -712,9 +715,9 @@ struct GitRepoImpl : GitRepo, std::enable_shared_from_this<GitRepoImpl>
     }
 };
 
-ref<GitRepo> GitRepo::openRepo(const std::filesystem::path & path, bool create, bool bare, bool packfilesOnly)
+ref<GitRepo> GitRepo::openRepo(const std::filesystem::path & path, GitRepo::Options options)
 {
-    return make_ref<GitRepoImpl>(path, create, bare, packfilesOnly);
+    return make_ref<GitRepoImpl>(path, options);
 }
 
 /**
@@ -1428,7 +1431,7 @@ namespace fetchers {
 ref<GitRepo> Settings::getTarballCache() const
 {
     static auto repoDir = std::filesystem::path(getCacheDir()) / "tarball-cache";
-    return GitRepo::openRepo(repoDir, /*create=*/true, /*bare=*/true, /*packfilesOnly=*/true);
+    return GitRepo::openRepo(repoDir, {.create = true, .bare = true, .packfilesOnly = true});
 }
 
 } // namespace fetchers
@@ -1442,7 +1445,7 @@ GitRepo::WorkdirInfo GitRepo::getCachedWorkdirInfo(const std::filesystem::path &
         if (i != cache->end())
             return i->second;
     }
-    auto workdirInfo = GitRepo::openRepo(path)->getWorkdirInfo();
+    auto workdirInfo = GitRepo::openRepo(path, {})->getWorkdirInfo();
     _cache.lock()->emplace(path, workdirInfo);
     return workdirInfo;
 }

src/libfetchers/git.cc

@@ -637,11 +637,6 @@ struct GitInputScheme : InputScheme
                     url);
             }
 
-            // If we don't check here for the path existence, then we can give libgit2 any directory
-            // and it will initialize them as git directories.
-            if (!pathExists(path)) {
-                throw Error("The path '%s' does not exist.", path);
-            }
             repoInfo.location = std::filesystem::absolute(path);
         } else {
             if (url.scheme == "file")
@@ -703,7 +698,7 @@ struct GitInputScheme : InputScheme
         if (auto res = cache->lookup(key))
             return getIntAttr(*res, "lastModified");
 
-        auto lastModified = GitRepo::openRepo(repoDir)->getLastModified(rev);
+        auto lastModified = GitRepo::openRepo(repoDir, {})->getLastModified(rev);
 
         cache->upsert(key, {{"lastModified", lastModified}});
 
@@ -726,7 +721,7 @@ struct GitInputScheme : InputScheme
         Activity act(
             *logger, lvlChatty, actUnknown, fmt("getting Git revision count of '%s'", repoInfo.locationToArg()));
 
-        auto revCount = GitRepo::openRepo(repoDir)->getRevCount(rev);
+        auto revCount = GitRepo::openRepo(repoDir, {})->getRevCount(rev);
 
         cache->upsert(key, Attrs{{"revCount", revCount}});
 
@@ -737,7 +732,7 @@ struct GitInputScheme : InputScheme
     {
         auto head = std::visit(
             overloaded{
-                [&](const std::filesystem::path & path) { return GitRepo::openRepo(path)->getWorkdirRef(); },
+                [&](const std::filesystem::path & path) { return GitRepo::openRepo(path, {})->getWorkdirRef(); },
                 [&](const ParsedURL & url) { return readHeadCached(url.to_string(), shallow); }},
             repoInfo.location);
         if (!head) {
@@ -795,7 +790,7 @@ struct GitInputScheme : InputScheme
         if (auto repoPath = repoInfo.getPath()) {
             repoDir = *repoPath;
             if (!input.getRev())
-                input.attrs.insert_or_assign("rev", GitRepo::openRepo(repoDir)->resolveRef(ref).gitRev());
+                input.attrs.insert_or_assign("rev", GitRepo::openRepo(repoDir, {})->resolveRef(ref).gitRev());
         } else {
             auto repoUrl = std::get<ParsedURL>(repoInfo.location);
             std::filesystem::path cacheDir = getCachePath(repoUrl.to_string(), shallow);
@@ -805,7 +800,7 @@ struct GitInputScheme : InputScheme
             std::filesystem::create_directories(cacheDir.parent_path());
             PathLocks cacheDirLock({cacheDir.string()});
 
-            auto repo = GitRepo::openRepo(cacheDir, true, true);
+            auto repo = GitRepo::openRepo(cacheDir, {.create = true, .bare = true});
 
             // We need to set the origin so resolving submodule URLs works
             repo->setRemote("origin", repoUrl.to_string());
@@ -876,7 +871,7 @@ struct GitInputScheme : InputScheme
             // the remainder
         }
 
-        auto repo = GitRepo::openRepo(repoDir);
+        auto repo = GitRepo::openRepo(repoDir, {});
 
         auto isShallow = repo->isShallow();
 
@@ -963,7 +958,7 @@ struct GitInputScheme : InputScheme
             for (auto & submodule : repoInfo.workdirInfo.submodules)
                 repoInfo.workdirInfo.files.insert(submodule.path);
 
-        auto repo = GitRepo::openRepo(repoPath, false, false);
+        auto repo = GitRepo::openRepo(repoPath, {});
 
         auto exportIgnore = getExportIgnoreAttr(input);
 
@@ -1003,7 +998,7 @@ struct GitInputScheme : InputScheme
         }
 
         if (!repoInfo.workdirInfo.isDirty) {
-            auto repo = GitRepo::openRepo(repoPath);
+            auto repo = GitRepo::openRepo(repoPath, {});
 
             if (auto ref = repo->getWorkdirRef())
                 input.attrs.insert_or_assign("ref", *ref);

src/libfetchers/include/nix/fetchers/git-utils.hh

@@ -32,8 +32,14 @@ struct GitRepo
 {
     virtual ~GitRepo() {}
 
-    static ref<GitRepo>
-    openRepo(const std::filesystem::path & path, bool create = false, bool bare = false, bool packfilesOnly = false);
+    struct Options
+    {
+        bool create = false;
+        bool bare = false;
+        bool packfilesOnly = false;
+    };
+
+    static ref<GitRepo> openRepo(const std::filesystem::path & path, Options options);
 
     virtual uint64_t getRevCount(const Hash & rev) = 0;