Write setuptools' setup_requires and tests_require to a file in egg_info. As is always the case with setuptools, it still installs setup_requires as a side effect.

acmd.py

def requires_writer(cmd, basename, filename):
    cmd.write_file("setup_requires", filename, 
            str(cmd.distribution.setup_requires) + '\n' + 
            str(cmd.distribution.tests_require) + '\n')

setup.py

from setuptools import setup

setup(name='acmd',
      version='1.0',
      description="Write setup_requires.txt to egg_info",
      py_modules = ['acmd'],
      setup_requires = ['pip', 'wheel', 'setuptools'],
      tests_require = ['simplejson'],
      zip_safe=False,
      entry_points={
          "egg_info.writers": [
              "setup_requires.txt = acmd:requires_writer"
              ]
          }
      )