code: def test_GitRepo_git_get_branch_commits_(src=None):
      repo = GitRepo(src, create=True)
      with open(op.join(src, "file.txt"), "w") as f:
          f.write("load")
      repo.add("*")
      repo.commit("committing")
      # go in a branch with a name that matches the file to require
      # proper disambiguation
      repo.call_git(["checkout", "-b", "file.txt"])
  
      commits_default = list(repo.get_branch_commits_())
      commits = list(repo.get_branch_commits_(DEFAULT_BRANCH))
      eq_(commits, commits_default)
      eq_(len(commits), 1)
  
imports: import logging
  import os
  import os.path
  import sys
  import pytest
  from datalad import get_encoding_info
  from datalad.cmd import StdOutCapture, StdOutErrCapture, WitlessRunner
  from datalad.support.exceptions import CommandError, FileNotInRepositoryError, InvalidGitRepositoryError, NoSuchPathError, PathKnownToRepositoryError
  from datalad.support.external_versions import external_versions
  from datalad.support.gitrepo import GitRepo, _normalize_path, normalize_paths, to_options
  from datalad.support.sshconnector import get_connection_hash
  from datalad.tests.utils_pytest import DEFAULT_BRANCH, DEFAULT_REMOTE, SkipTest, assert_cwd_unchanged, assert_equal, assert_false, assert_in, assert_in_results, assert_is_instance, assert_not_equal, assert_not_in, assert_raises, assert_repo_status, assert_true, create_tree, eq_, get_most_obscure_supported_name, integration, neq_, ok_, skip_if_no_network, skip_if_on_windows, skip_nomultiplex_ssh, slow, swallow_logs, with_tempfile, with_tree, xfail_buggy_annex_info
  from datalad.utils import Path, chpwd, getpwd, on_windows, rmtree
label_desc: Use image node_id 28 for calling a global function with example usage: test_GitRepo_git_get_branch_commits_(src) without return types