old_contents: import os
  
  import pytest
  from whichcraft import which
  
  
  def test_existing_command():
      cmd = which("date")
      assert cmd
      assert os.path.exists(cmd)
      assert os.access(cmd, os.F_OK | os.X_OK)
      assert not os.path.isdir(cmd)
  
  
  def test_non_existing_command():
      assert which("stringthatisntashellcommand") is None
  
  
  if __name__ == "__main__":
      pytest.main()
  
new_contents: import os
  from datetime import date
  import pytest
  from whichcraft import which
  import sys
  
  @pytest.mark.skipif(sys.platform == "win32", reason= "Does not run on windows")
  def test_existing_linux():
      cmd = which("date")
      assert cmd
      assert os.path.exists(cmd)
      assert os.access(cmd, os.F_OK | os.X_OK)
      assert not os.path.isdir(cmd)
  
  
  def test_non_existing_command():
      assert which("stringthatisntashellcommand") is None
  
  @pytest.mark.skipif(sys.platform != "win32", reason= "Does not run on windows")
  def test_existing_windows():
      cmd = which("cmd")
      assert cmd
      assert os.path.exists(cmd)
      assert os.access(cmd, os.F_OK | os.X_OK)
      assert not os.path.isdir(cmd)
  
  
  if __name__ == "__main__":
      pytest.main()
  
subject: Update test_whichcraft.py