parameters: (since, repo)
docstring: find the common base commit of the current HEAD and provided since.
docstring_summary: find the common base commit of the current HEAD and provided since.
docstring_tokens: find the common base commit of the current HEAD and provided since .
function: def get_since_commit(since, repo):
      """find the common base commit of the current HEAD and provided since."""
      try:
          since_commit = repo.commit(since)
      except (gitdb.exc.BadName, ValueError):
          logger.error("{} does not resolve to a git commit".format(since))
          raise
      try:
          return git_util.find_common_ancestor(since_commit, repo.head.commit)
      except (git_util.NoCommonAncestor):
          logger.error(
              "No common ancestor for the following commits:\n  {}\n  {}".format(
                  git_util.commit_to_human(since_commit),
                  git_util.commit_to_human(repo.head.commit),
              )
          )
          raise
      except (git_util.MultipleCommonAncestors):
          logger.error(
              (
                  "Multiple common ancestors for the following " "commits:\n  {}\n  {}"
              ).format(
                  git_util.commit_to_human(since_commit),
                  git_util.commit_to_human(repo.head.commit),
              )
          )
          raise
function_tokens: def get_since_commit ( since , repo ) : try : since_commit = repo . commit ( since ) except ( gitdb . exc . BadName , ValueError ) : logger . error ( "{} does not resolve to a git commit" . format ( since ) ) raise try : return git_util . find_common_ancestor ( since_commit , repo . head . commit ) except ( git_util . NoCommonAncestor ) : logger . error ( "No common ancestor for the following commits:\n  {}\n  {}" . format ( git_util . commit_to_human ( since_commit ) , git_util . commit_to_human ( repo . head . commit ) , ) ) raise except ( git_util . MultipleCommonAncestors ) : logger . error ( ( "Multiple common ancestors for the following " "commits:\n  {}\n  {}" ) . format ( git_util . commit_to_human ( since_commit ) , git_util . commit_to_human ( repo . head . commit ) , ) ) raise