1 files changed, 57 insertions, 0 deletions
diff --git a/src/libfetchers/git.cc b/src/libfetchers/git.cc
index 7c18cf67f..210e29193 100644
--- a/src/libfetchers/git.cc
+++ b/src/libfetchers/git.cc
@@ -79,6 +79,63 @@ struct GitInput : Input
         return attrs;
     }
 
+    void clone(const Path & destDir) const override
+    {
+        auto [isLocal, actualUrl] = getActualUrl();
+
+        Strings args = {"clone"};
+
+        args.push_back(actualUrl);
+
+        if (ref) {
+            args.push_back("--branch");
+            args.push_back(*ref);
+        }
+
+        if (rev) throw Error("cloning a specific revision is not implemented");
+
+        args.push_back(destDir);
+
+        runProgram("git", true, args);
+    }
+
+    std::shared_ptr<const Input> applyOverrides(
+        std::optional<std::string> ref,
+        std::optional<Hash> rev) const override
+    {
+        if (!ref && !rev) return shared_from_this();
+
+        auto res = std::make_shared<GitInput>(*this);
+
+        if (ref) res->ref = ref;
+        if (rev) res->rev = rev;
+
+        if (!res->ref && res->rev)
+            throw Error("Git input '%s' has a commit hash but no branch/tag name", res->to_string());
+
+        return res;
+    }
+
+    std::optional<Path> getSourcePath() const override
+    {
+        if (url.scheme == "file" && !ref && !rev)
+            return url.path;
+        return {};
+    }
+
+    void markChangedFile(std::string_view file, std::optional<std::string> commitMsg) const override
+    {
+        auto sourcePath = getSourcePath();
+        assert(sourcePath);
+
+        runProgram("git", true,
+            { "-C", *sourcePath, "add", "--force", "--intent-to-add", std::string(file) });
+
+        if (commitMsg)
+            runProgram("git", true,
+                { "-C", *sourcePath, "commit", std::string(file), "-m", *commitMsg });
+    }
+
     std::pair<bool, std::string> getActualUrl() const
     {
         // Don't clone file:// URIs (but otherwise treat them the