Fix pushing of new branches from porcelain.push. Fixes #788

NEWS

@@ -3,6 +3,9 @@
  * Add a ``RefsContainer.watch`` interface.
    (Jelmer Vernooij, #751)
 
+ * Fix pushing of new branches from porcelain.push.
+   (Jelmer Vernooij, #788)
+
 0.20.5	2020-06-22
 
  * Print a clearer exception when setup.py is executed on Python < 3.5.

dulwich/porcelain.py

@@ -975,10 +975,15 @@ def push(repo, remote_location=None, refspecs=None,
                     new_refs[rh] = ZERO_SHA
                     remote_changed_refs[rh] = None
                 else:
-                    if not force_ref:
-                        check_diverged(r, refs[rh], r.refs[lh])
-                    new_refs[rh] = r.refs[lh]
-                    remote_changed_refs[rh] = r.refs[lh]
+                    try:
+                        localsha = r.refs[lh]
+                    except KeyError:
+                        raise Error(
+                            'No valid ref %s in local repository' % lh)
+                    if not force_ref and rh in refs:
+                        check_diverged(r, refs[rh], localsha)
+                    new_refs[rh] = localsha
+                    remote_changed_refs[rh] = localsha
             return new_refs
 
         err_encoding = getattr(errstream, 'encoding', None) or DEFAULT_ENCODING

dulwich/tests/test_porcelain.py

@@ -925,6 +925,53 @@ class PushTests(PorcelainTestCase):
             self.assertEqual(os.path.basename(fullpath),
                              change.new.path.decode('ascii'))
 
+    def test_local_missing(self):
+        """Pushing a new branch."""
+        outstream = BytesIO()
+        errstream = BytesIO()
+
+        # Setup target repo cloned from temp test repo
+        clone_path = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, clone_path)
+        target_repo = porcelain.init(clone_path)
+        target_repo.close()
+
+        self.assertRaises(
+            porcelain.Error,
+            porcelain.push, self.repo, clone_path,
+            b"HEAD:refs/heads/master",
+            outstream=outstream, errstream=errstream)
+
+    def test_new(self):
+        """Pushing a new branch."""
+        outstream = BytesIO()
+        errstream = BytesIO()
+
+        # Setup target repo cloned from temp test repo
+        clone_path = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, clone_path)
+        target_repo = porcelain.init(clone_path)
+        target_repo.close()
+
+        # create a second file to be pushed back to origin
+        handle, fullpath = tempfile.mkstemp(dir=clone_path)
+        os.close(handle)
+        porcelain.add(repo=clone_path, paths=[fullpath])
+        new_id = porcelain.commit(
+            repo=self.repo, message=b'push',
+            author=b'author <email>',
+            committer=b'committer <email>')
+
+        # Push to the remote
+        porcelain.push(self.repo, clone_path, b"HEAD:refs/heads/master",
+                       outstream=outstream, errstream=errstream)
+
+        with Repo(clone_path) as r_clone:
+            self.assertEqual({
+                b'HEAD': new_id,
+                b'refs/heads/master': new_id,
+                }, r_clone.get_refs())
+
     def test_delete(self):
         """Basic test of porcelain push, removing a branch.
         """