Repository: sigmavirus24/github3.py (python)

Issue:
`Branch.sync_with_upstream` sends incomplete data
Hello, first of all thank you so much for this incredible library!

I tried to sync my repos default branches with upstream using `Branch.sync_with_upstream`, but it failed with `github3.exceptions.ForbiddenError: 403 Resource not accessible by personal access token`.

Comparing the data sent by github3.py with the curl example in the GH API docs, it seems like we are missing the content added by that command's `-d '{"branch":"main"}'`.

I'll submit a PR to fix this, but wanted to file this issue so you can mention it if another solution is deemed more appropriate.

Edited to add (from template that was only shown at new PR creation):


## Version Information

Python: 3.12. 7
pip: 24.2
github3.py: 4.0.1, also git at [3b31f12](https://github.com/devdanzin/github3.py/commit/3b31f12f6b74b44e6828cde9264cd2402c0bd782)
requests: 2.32.3
uritemplate: 4.1.1
python-dateutil: 2.9.0.post0

## Minimum Reproducible Example

```python
def sync_default_branches():
    user = github3.login(USER, token=AUTH_TOKEN)
    repositories: typing.Generator[github3.github.repo.ShortRepository] = user.repositories(
        number=5, sort="fullname"
    )

    for repo in repositories:
        full_repo: [github3.github.repo.Repository] = repo.refresh()
        default_branch: github3.github.repo.branch.Branch = full_repo.branch(full_repo.default_branch)
        print(f"Syncing branch {default_branch.name} in {full_repo.full_name}.")
        try:
            result = default_branch.sync_with_upstream()
            print(result)
            print("Done\n")
        except Exception as e:
            print(f"Failed to sync branch {default_branch.name}: {e}\n")
```

## Exception information

Syncing doesn't work, but it does if we send `'{"branch":"NAME_OF_BRANCH"}'` in the request.

Pull request description:
Update `Branch.sync_with_upstream` to correcly send required data.
This PR adds `data={"branch": self.name}` to the request made by `Branch.sync_with_upstream`, in conformance with the corresponding [API docs](https://docs.github.com/en/rest/branches/branches?apiVersion=2022-11-28#sync-a-fork-branch-with-the-upstream-repository). Also removes the mention that this is a beta feature as I didn't see it in the docs. Contains new tests.

Please let me know if there's anything I can do to improve the code, the PR itself or anything else.

Fixes #1198.

Thank you!

Patch:
diff --git a/AUTHORS.rst b/AUTHORS.rst
index 1946eda3..c28d9b35 100644
--- a/AUTHORS.rst
+++ b/AUTHORS.rst
@@ -226,3 +226,5 @@ Contributors
 - Thomas Buchner (@MrBatschner)
 
 - Chris Cotter (@ccotter)
+
+- Daniel Diniz (@devdanzin)
diff --git a/src/github3/repos/branch.py b/src/github3/repos/branch.py
index 8ebaaeb7..8b941a57 100644
--- a/src/github3/repos/branch.py
+++ b/src/github3/repos/branch.py
@@ -166,17 +166,13 @@ class _Branch(models.GitHubCore):
     def sync_with_upstream(self) -> t.Mapping[str, str]:
         """Synchronize this branch with the upstream.
 
-        .. warning::
-
-            This API endpoint is still in Beta per gitHub
-
         .. versionadded:: 3.0.0
 
         Sync a branch of a forked repository to keep it up-to-date with the
         upstream repository.
 
         See also:
-        https://docs.github.com/en/rest/reference/repos#sync-a-fork-branch-with-the-upstream-repository
+        https://docs.github.com/en/rest/branches/branches#sync-a-fork-branch-with-the-upstream-repository
 
         :returns:
             The dictionary described in the documentation
@@ -185,7 +181,7 @@ class _Branch(models.GitHubCore):
         """
         base = self._api.split("/branches", 1)[0]
         url = self._build_url("merge-upstream", base_url=base)
-        json = self._json(self._post(url), 200)
+        json = self._json(self._post(url, data={"branch": self.name}), 200)
         return json
 
     @decorators.requires_auth


Test patch:
diff --git a/tests/cassettes/Branch_sync_with_upstream.json b/tests/cassettes/Branch_sync_with_upstream.json
new file mode 100644
index 00000000..aacdb812
--- /dev/null
+++ b/tests/cassettes/Branch_sync_with_upstream.json
@@ -0,0 +1,1 @@
+{"http_interactions": [{"request": {"body": {"encoding": "utf-8", "string": ""}, "headers": {"User-Agent": ["github3.py/4.0.1"], "Accept-Encoding": ["gzip, deflate"], "Accept": ["application/vnd.github.v3.full+json"], "Connection": ["keep-alive"], "Accept-Charset": ["utf-8"], "Content-Type": ["application/json"], "Authorization": ["token <AUTH_TOKEN>"]}, "method": "GET", "uri": "https://api.github.com/repos/devdanzin/cpython"}, "response": {"body": {"encoding": "utf-8", "base64_string": "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", "string": ""}, "headers": {"Date": ["Thu, 17 Oct 2024 15:20:14 GMT"], "Content-Type": ["application/json; 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diff --git a/tests/integration/test_repos_branch.py b/tests/integration/test_repos_branch.py
index 63aef805..c77d1e80 100644
--- a/tests/integration/test_repos_branch.py
+++ b/tests/integration/test_repos_branch.py
@@ -33,3 +33,22 @@ class TestBranch(IntegrationHelper):
             latest_sha = branch.latest_sha(differs_from=sha)
 
         assert not isinstance(latest_sha, bytes)
+
+    def test_sync_with_upstream(self):
+        self.token_login()
+        cassette_name = self.cassette_name("sync_with_upstream")
+        betamax_kwargs = {
+            "match_requests_on": ["method", "uri", "if-none-match"]
+        }
+        with self.recorder.use_cassette(cassette_name, **betamax_kwargs):
+            repository = self.gh.repository("devdanzin", "cpython")
+            branch = repository.branch("main")
+            result = branch.sync_with_upstream()
+
+        msg = (
+            "Successfully fetched and fast-forwarded"
+            " from upstream python:main."
+        )
+        assert result["message"] == msg
+        assert result["merge_type"] == "fast-forward"
+        assert result["base_branch"] == "python:main"
diff --git a/tests/unit/test_repos_branch.py b/tests/unit/test_repos_branch.py
index f381e200..72580a35 100644
--- a/tests/unit/test_repos_branch.py
+++ b/tests/unit/test_repos_branch.py
@@ -11,6 +11,9 @@ url_for_branches = helper.create_url_helper(
 url_for_commits = helper.create_url_helper(
     "https://api.github.com/repos/octocat/Hello-World/commits/master"
 )
+url_for_sync = helper.create_url_helper(
+    "https://api.github.com/repos/octocat/Hello-World/merge-upstream"
+)
 
 
 class TestBranch(helper.UnitHelper):
@@ -30,6 +33,13 @@ class TestBranch(helper.UnitHelper):
             url_for_commits(), headers=headers
         )
 
+    def test_sync_with_upstream(self):
+        """Verify the request fot syncing a branch with upstream."""
+        self.instance.sync_with_upstream()
+        self.session.post.assert_called_once_with(
+            url_for_sync(), '{"branch": "master"}'
+        )
+
     def test_unprotect(self):
         """Verify the request to unprotect a branch."""
         self.instance.unprotect()
@@ -44,6 +54,10 @@ class TestBranchRequiresAuth(helper.UnitRequiresAuthenticationHelper):
     described_class = github3.repos.branch.Branch
     example_data = get_example_data()
 
+    def test_sync_with_upstream(self):
+        """Verify that branch syncing with upstream requires authentication."""
+        self.assert_requires_auth(self.instance.sync_with_upstream)
+
     def test_protect(self):
         """Verify that protecting a branch requires authentication."""
         self.assert_requires_auth(self.instance.protect)