CircleCI Parallelization

circleci.sh

$ circleci tests glob "test/integration/**/test_*.py"
test/integration/test_1.py
test/integration/test_2.py
test/integration/test_3.py
test/integration/test_4.py
test/integration/test_5.py
test/integration/test_6.py
test/integration/test_7.py
test/integration/test_8.py

$ circleci tests split --total 4 --index 0
test/integration/test_1.py
test/integration/test_5.py

$ CIRCLE_NODE_TOTAL=4
$ CIRCLE_NODE_INDEX=0
$ circleci tests split
test/integration/test_1.py
test/integration/test_5.py

config.yaml

integration-tests:
  parallelism: 8
  docker:
    - image: circleci/python:3.7-stretch
  steps:
    - run:
        name: Split tests and run them
        command: |
          TEST_FILES=$(circleci tests glob "test/integration/**/test_*.py" | circleci tests split)
          bin/test.py integration "$(echo $TEST_FILES)"