GitPython is failing to retrieve commits from a specific repository I am currently analyzing: https://github.com/jbrowncfa/Cryptobomb.

Exception's stack trace:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.6/site-packages/git/repo/base.py", line 524, in iter_commits
    rev = self.head.commit
  File "/usr/local/lib/python3.6/site-packages/git/refs/symbolic.py", line 197, in _get_commit
    obj = self._get_object()
  File "/usr/local/lib/python3.6/site-packages/git/refs/symbolic.py", line 190, in _get_object
    return Object.new_from_sha(self.repo, hex_to_bin(self.dereference_recursive(self.repo, self.path)))
  File "/usr/local/lib/python3.6/site-packages/git/objects/base.py", line 64, in new_from_sha
    oinfo = repo.odb.info(sha1)
  File "/usr/local/lib/python3.6/site-packages/git/db.py", line 37, in info
    hexsha, typename, size = self._git.get_object_header(bin_to_hex(sha))
  File "/usr/local/lib/python3.6/site-packages/git/cmd.py", line 1068, in get_object_header
    return self.__get_object_header(cmd, ref)
  File "/usr/local/lib/python3.6/site-packages/git/cmd.py", line 1057, in __get_object_header
    return self._parse_object_header(cmd.stdout.readline())
  File "/usr/local/lib/python3.6/site-packages/git/cmd.py", line 1019, in _parse_object_header
    raise ValueError("SHA could not be resolved, git returned: %r" % (header_line.strip()))
ValueError: SHA could not be resolved, git returned: b''

Reproducible example:

$ git clone https://github.com/jbrowncfa/Cryptobomb

from git import Repo
repo = Repo("./Cryptobomb")
for commit in repo.iter_commits():
    print(commit.hexsha) # error

Here is the Dockerfile I'm using:

FROM python:3.6

ENV GIT_DISCOVERY_ACROSS_FILESYSTEM=1
RUN apt-get update
RUN apt-get install -y git 

Please let me know if you guys need any more info.