code: def test_diff_add_similar_files(tmp_dir, scm, dvc, commit_last):
      if commit_last:
          last_commit_msg = "commit #2"
          a_rev = "HEAD~1"
      else:
          last_commit_msg = None
          a_rev = "HEAD"
  
      tmp_dir.dvc_gen(
          {"dir": {"file": "text1", "subdir": {"file2": "text2"}}},
          commit="commit #1",
      )
      tmp_dir.dvc_gen(
          {"dir2": {"file": "text1", "subdir": {"file2": "text2"}}},
          commit=last_commit_msg,
      )
  
      assert dvc.diff(a_rev) == {
          "added": [
              {
                  "path": os.path.join("dir2", ""),
                  "hash": "cb58ee07cb01044db229e4d6121a0dfc.dir",
              },
              {
                  "path": os.path.join("dir2", "file"),
                  "hash": "cef7ccd89dacf1ced6f5ec91d759953f",
              },
              {
                  "path": os.path.join("dir2", "subdir", "file2"),
                  "hash": "fe6123a759017e4a2af4a2d19961ed71",
              },
          ],
          "deleted": [],
          "modified": [],
          "renamed": [],
          "not in cache": [],
      }
  
imports: import hashlib
  import os
  import pytest
  from funcy import first
  from dvc.exceptions import DvcException
  from dvc.utils.fs import remove
label_desc: Use image node_id 26 for calling a global function with example usage: test_diff_add_similar_files(tmp_dir, scm, dvc, commit_last) without return types