count_warnings.py

import os
import sys
import glob
import subprocess
import warnings
warnings.simplefilter('ignore')

for subpackage in sorted(glob.glob(os.path.join('astropy', '*'))):
    if os.path.isdir(subpackage) and '_' not in subpackage and 'extern' not in subpackage:
        output = subprocess.check_output([sys.executable, '-m', 'pytest', subpackage])
        nwarn = 0
        for line in output.splitlines():
            if b'seconds ======' in line:
                if b'warnings' in line:
                    nwarn = int(line.split(b'warnings')[0].split()[-1])
                    break
        print(f'{subpackage}: {nwarn}')