pytest: report general memory leakage of tests (beyond threshold)

conftest.py

# pytest: report general memory leakage of tests (beyond threshold)
# from https://nvbn.github.io/2017/02/02/pytest-leaking/
# add the following code to tests/conftest.py in your test suite and run `pytest`
import os
from psutil import Process

_proc = Process(os.getpid())

def get_consumed_ram():
    return _proc.memory_info().rss

from collections import namedtuple

START = 'START'
END = 'END'
ConsumedRamLogEntry = namedtuple('ConsumedRamLogEntry', ('nodeid', 'on', 'consumed_ram'))
consumed_ram_log = []

def pytest_runtest_setup(item):
    log_entry = ConsumedRamLogEntry(item.nodeid, START, get_consumed_ram())
    consumed_ram_log.append(log_entry)

def pytest_runtest_teardown(item):
    log_entry = ConsumedRamLogEntry(item.nodeid, END, get_consumed_ram())
    consumed_ram_log.append(log_entry)
from itertools import groupby

LEAK_LIMIT = 10 * 1024 * 1024

def pytest_terminal_summary(terminalreporter):
    print("SUMMARY")
    grouped = groupby(consumed_ram_log, lambda entry: entry.nodeid)
    for nodeid, (start_entry, end_entry) in grouped:
        leaked = end_entry.consumed_ram - start_entry.consumed_ram
        if leaked > LEAK_LIMIT:
            terminalreporter.write('LEAKED {}MB in {}\n'.format(
                leaked / 1024 / 1024, nodeid))