text: import copy
  import os
  from contextlib import contextmanager
  
  from funcy import merge
  
  from .local import DependencyLOCAL
  from dvc.external_repo import cached_clone
  from dvc.external_repo import external_repo
  from dvc.exceptions import NotDvcRepoError
  from dvc.exceptions import OutputNotFoundError
  from dvc.exceptions import NoOutputInExternalRepoError
  from dvc.exceptions import PathMissingError
  from dvc.utils.fs import fs_copy
  from dvc.path_info import PathInfo
  from dvc.scm import SCM
  
  
  class DependencyREPO(DependencyLOCAL):
      PARAM_REPO = "repo"
      PARAM_URL = "url"
      PARAM_REV = "rev"
      PARAM_REV_LOCK = "rev_lock"
  
      REPO_SCHEMA = {PARAM_URL: str, PARAM_REV: str, PARAM_REV_LOCK: str}
  
      def __init__(self, def_repo, stage, *args, **kwargs):
          self.def_repo = def_repo
          super().__init__(stage, *args, **kwargs)
  
      def _parse_path(self, remote, path):
          return None
  
      @property
      def is_in_repo(self):
          return False
  
      @property
      def repo_pair(self):
          d = self.def_repo
          return d[self.PARAM_URL], d[self.PARAM_REV_LOCK] or d[self.PARAM_REV]
  
      def __str__(self):
          return "{} ({})".format(self.def_path, self.def_repo[self.PARAM_URL])
  
      @contextmanager
      def _make_repo(self, **overrides):
          with external_repo(**merge(self.def_repo, overrides)) as repo:
              yield repo
  
      def _get_checksum(self, updated=False):
          rev_lock = None
          if not updated:
              rev_lock = self.def_repo.get(self.PARAM_REV_LOCK)
  
          try:
              with self._make_repo(rev_lock=rev_lock) as repo:
                  return repo.find_out_by_relpath(self.def_path).info["md5"]
          except (NotDvcRepoError, NoOutputInExternalRepoError):
              # Fall through and clone
              pass
  
          repo_path = cached_clone(
              self.def_repo[self.PARAM_URL],
              rev=rev_lock or self.def_repo.get(self.PARAM_REV),
          )
          path = PathInfo(os.path.join(repo_path, self.def_path))
  
          return self.repo.cache.local.get_checksum(path)
  
      def status(self):
          current_checksum = self._get_checksum(updated=False)
          updated_checksum = self._get_checksum(updated=True)
  
          if current_checksum != updated_checksum:
              return {str(self): "update available"}
  
          return {}
  
      def save(self):
          pass
  
      def dumpd(self):
          return {self.PARAM_PATH: self.def_path, self.PARAM_REPO: self.def_repo}
  
      def fetch(self):
          with self._make_repo(
              cache_dir=self.repo.cache.local.cache_dir
          ) as repo:
              self.def_repo[self.PARAM_REV_LOCK] = repo.scm.get_rev()
  
              out = repo.find_out_by_relpath(self.def_path)
              with repo.state:
                  repo.cloud.pull(out.get_used_cache())
  
          return out
  
      @staticmethod
      def _is_git_file(repo_dir, path):
          from dvc.repo import Repo
  
          if os.path.isabs(path):
              return False
  
          try:
              repo = Repo(repo_dir)
          except NotDvcRepoError:
              return True
  
          try:
              output = repo.find_out_by_relpath(path)
              return not output.use_cache
          except OutputNotFoundError:
              return True
          finally:
              repo.close()
  
      def _copy_if_git_file(self, to_path):
          src_path = self.def_path
          repo_dir = cached_clone(**self.def_repo)
  
          if not self._is_git_file(repo_dir, src_path):
              return False
  
          src_full_path = os.path.join(repo_dir, src_path)
          dst_full_path = os.path.abspath(to_path)
          fs_copy(src_full_path, dst_full_path)
          self.def_repo[self.PARAM_REV_LOCK] = SCM(repo_dir).get_rev()
          return True
  
      def download(self, to):
          try:
              if self._copy_if_git_file(to.fspath):
                  return
  
              out = self.fetch()
              to.info = copy.copy(out.info)
              to.checkout()
          except (FileNotFoundError):
              raise PathMissingError(
                  self.def_path, self.def_repo[self.PARAM_URL]
              )
  
      def update(self):
          with self._make_repo(rev_lock=None) as repo:
              self.def_repo[self.PARAM_REV_LOCK] = repo.scm.get_rev()
  