test_randomness.py

 
 
'''
We generate, simulate and reconstruct few events with two different processes
and we check the two processes give exactly the same output.
'''
 
 
import difflib
import subprocess
 
import basf2 as b2
import b2test_utils as b2tu
 
 
def _unified_diff(expected, actual):
    '''
    Helper function. Returns a string containing the unified diff of two multiline strings.
    '''
    expected = expected.splitlines(1)
    actual = actual.splitlines(1)
    diff = difflib.unified_diff(expected, actual)
    return ''.join(diff)
 
 
if __name__ == '__main__':
 
    steering = b2.find_file('reconstruction/tests/test_randomness.py_noexec')
    command = f'basf2 {steering} -n 10 --random-seed aSeed'
 
    b2.B2INFO('Executing first job...')
    with b2tu.clean_working_directory():
        job1 = subprocess.run(command.split(), check=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, text=True)
 
    b2.B2INFO('Executing second job...')
    with b2tu.clean_working_directory():
        job2 = subprocess.run(command.split(), check=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, text=True)
 
    diff = _unified_diff(job1.stdout, job2.stdout)
    if diff:
        b2.B2ERROR('!!! The two outputs are different !!!')
        print(diff)
        b2.B2FATAL('!!! basf2 produces irreproducible results !!!')