old_contents: """Coverage-test Coverage itself."""
  
  import coverage
  import os, shutil, sys
  
  HTML_DIR = "htmlcov"
  
  if os.path.exists(HTML_DIR):
      shutil.rmtree(HTML_DIR)
  
  cov = coverage.coverage()
  # Cheap trick: the coverage code itself is excluded from measurement, but if
  # we clobber the cover_prefix in the coverage object, we can defeat the
  # self-detection.
  cov.cover_prefix = "Please measure coverage.py!"
  cov.erase()
  cov.start()
  
  # Re-import coverage to get it coverage tested!  I don't understand all the
  # mechanics here, but if I don't carry over the imported modules (in covmods),
  # then things go haywire (os == None eventually).
  covmods = {}
  covdir = os.path.split(coverage.__file__)
  for name, mod in sys.modules.items():
      if name.startswith('coverage'):
          if hasattr(mod, '__file__') and mod.__file__.startswith(covdir):
              covmods[name] = mod
              del sys.modules[name]
  import coverage     # don't warn about re-import: pylint: disable-msg=W0404
  sys.modules.update(covmods)
  
  # Run nosetests, with the arguments from our command line.
  import nose
  nose.run(sys.argv[1:])
  
  cov.stop()
  
  cov.clear_exclude()
  cov.exclude("#pragma: no cover")
  cov.exclude("def __repr__")
  cov.exclude("if __name__ == .__main__.:")
  
  cov.html_report(directory=HTML_DIR, ignore_errors=True)
  
new_contents: """Coverage-test Coverage itself."""
  
  import coverage
  import os, shutil, sys
  
  HTML_DIR = "htmlcov"
  
  if os.path.exists(HTML_DIR):
      shutil.rmtree(HTML_DIR)
  
  cov = coverage.coverage()
  # Cheap trick: the coverage code itself is excluded from measurement, but if
  # we clobber the cover_prefix in the coverage object, we can defeat the
  # self-detection.
  cov.cover_prefix = "Please measure coverage.py!"
  cov.erase()
  cov.start()
  
  # Re-import coverage to get it coverage tested!  I don't understand all the
  # mechanics here, but if I don't carry over the imported modules (in covmods),
  # then things go haywire (os == None eventually).
  covmods = {}
  covdir = os.path.split(coverage.__file__)
  for name, mod in sys.modules.items():
      if name.startswith('coverage'):
          if hasattr(mod, '__file__') and mod.__file__.startswith(covdir):
              covmods[name] = mod
              del sys.modules[name]
  import coverage     # don't warn about re-import: pylint: disable-msg=W0404
  sys.modules.update(covmods)
  
  # Run nosetests, with the arguments from our command line.
  import nose
  nose.run(sys.argv[1:])
  
  cov.stop()
  cov.save()
  
  cov.clear_exclude()
  cov.exclude("#pragma: no cover")
  cov.exclude("def __repr__")
  cov.exclude("if __name__ == .__main__.:")
  
  cov.html_report(directory=HTML_DIR, ignore_errors=True)
  
subject: Save .coverage when running our own coverage tests.