dulwich: preserve data from generators when retrying request

src/scmrepo/git/backend/dulwich/__init__.py

@@ -508,7 +508,7 @@ def iter_remote_refs(self, url: str, base: Optional[str] = None, **kwargs):
     def get_refs_containing(self, rev: str, pattern: Optional[str] = None):
         raise NotImplementedError
 
-    def push_refspecs(
+    def push_refspecs(  # noqa: C901
         self,
         url: str,
         refspecs: Union[str, Iterable[str]],
@@ -568,7 +568,7 @@ def update_refs(refs):
             return new_refs
 
         try:
-            client.send_pack(
+            result = client.send_pack(
                 path,
                 update_refs,
                 self.repo.object_store.generate_pack_data,
@@ -579,6 +579,17 @@ def update_refs(refs):
             raise SCMError(f"Git failed to push '{src}' to '{url}'") from exc
         except HTTPUnauthorized as exc:
             raise AuthError(url) from exc
+        if result.ref_status and any(
+            (value is not None) for value in result.ref_status.values()
+        ):
+            reasons = ", ".join(
+                (
+                    f"{os.fsdecode(ref)}: {reason}"
+                    for ref, reason in result.ref_status.items()
+                    if reason is not None
+                )
+            )
+            raise SCMError(f"Git failed to push some refs to '{url}' ({reasons})")
         return change_result
 
     def fetch_refspecs(

src/scmrepo/git/backend/dulwich/client.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, Optional
+from typing import Dict, Iterator, List, Optional, Union
 
 from dulwich.client import HTTPUnauthorized, Urllib3HttpGitClient
 
@@ -27,10 +27,28 @@ def _http_request(
         self,
         url: str,
         headers: Optional[Dict[str, str]] = None,
-        data: Any = None,
+        data: Optional[Union[bytes, Iterator[bytes]]] = None,
     ):
+        cached_chunks: List[bytes] = []
+
+        def _cached_data() -> Iterator[bytes]:
+            assert data is not None
+            if isinstance(data, bytes):
+                yield data
+                return
+
+            if cached_chunks:
+                yield from cached_chunks
+                return
+
+            for chunk in data:
+                cached_chunks.append(chunk)
+                yield chunk
+
         try:
-            result = super()._http_request(url, headers=headers, data=data)
+            result = super()._http_request(
+                url, headers=headers, data=None if data is None else _cached_data()
+            )
         except HTTPUnauthorized:
             auth_header = self._get_auth()
             if not auth_header:
@@ -39,7 +57,9 @@ def _http_request(
                 headers.update(auth_header)
             else:
                 headers = auth_header
-            result = super()._http_request(url, headers=headers, data=data)
+            result = super()._http_request(
+                url, headers=headers, data=None if data is None else _cached_data()
+            )
         if self._store_credentials is not None:
             self._store_credentials.approve()
         return result