.flake8

[flake8]
select = B,C,E,F,P,W,B9
max-line-length = 80
### DEFAULT IGNORES FOR 4-space INDENTED PROJECTS ###
# E127, E128 are hard to silence in certain nested formatting situations.
# E203 doesn't work for slicing
# E265, E266 talk about comment formatting which is too opinionated.
# E402 warns on imports coming after statements. There are important use cases
# like demandimport (https://fburl.com/demandimport) that require statements
# before imports.
# E501 is not flexible enough, we're using B950 instead.
# E722 is a duplicate of B001.
# P207 is a duplicate of B003.
# P208 is a duplicate of C403.
# W503 talks about operator formatting which is too opinionated.
ignore = E127, E128, E203, E265, E266, E402, E501, E722, P207, P208, W503
### DEFAULT IGNORES FOR 2-space INDENTED PROJECTS (uncomment) ###
# ignore = E111, E114, E121, E127, E128, E265, E266, E402, E501, P207, P208, W503
exclude =
  .git,
  .hg,
  __pycache__,
  _bin/*,
  _build/*,
  _ig_fbcode_wheel/*,
  buck-out/*,
  third-party-buck/*,
  third-party2/*

# Calculate max-complexity by changing the value below to 1, then surveying fbcode
# to see the distribution of complexity:
#   find ./[a-z0-9]* -name 'buck-*' -prune -o -name 'third*party*' -prune -o \
#     -name '*.py' -print |\
#   parallel flake8 --config ./.flake8 |\
#   perl -ne 'if (/C901/) { s/.*\((\d+)\)/$1/; print; }' | stats
# NOTE: This will take a while to run (near an hour IME) so you probably want a
# second working dir to run it in.
# Pick a reasonable point from there (e.g. p95 or "95%")
# As of 2016-05-18 the rough distribution is:
#
# count:    134807
# min:      2
# max:      206
# avg:      4.361
# median:   3
# sum:      587882
# stddev:   4.317
# variance: 18.635
#
# percentiles:
#     75%: 5
#     90%: 8
#     95%: 11
#     99%: 20
#   99.9%: 48
#  99.99%: 107
# 99.999%: 160
max-complexity = 12