Format with Black

[hugovk]

For #401

Locally:

# Install
pip install -U black

# Run
black .

Also run as part of:

pre-commit run --all-files

# Or
pre-commit run --all-files black

# Or
tox -e lint

Also run as part of the CI lint jobs.

[claudep]

You cannot imagine how I hate this black stuff, mostly polluting the git history for almost no gain :-( Sorry to be so negative about this.

[claudep]

Would you find it acceptable to work on flake8 integration and not using black (until my stubborn spirit get convinced)?

[hugovk]

Not really, I'd rather not manually fix dozens of styling/formatting changes if they can be (mostly) done automatically:

$ flake8 --statistics --count
./setup.py:10:57: W504 line break after binary operator
./tests/test_tablib.py:171:9: E731 do not assign a lambda expression, use a def
./tests/test_tablib_dbfpy_packages_utils.py:154:13: F841 local variable 'output' is assigned to but never used
./docs/conf.py:34:1: E265 block comment should start with '# '
./docs/conf.py:55:1: E265 block comment should start with '# '
./docs/conf.py:59:1: E265 block comment should start with '# '
./docs/conf.py:61:1: E265 block comment should start with '# '
./docs/conf.py:68:1: E265 block comment should start with '# '
./docs/conf.py:79:1: E265 block comment should start with '# '
./docs/conf.py:85:1: E265 block comment should start with '# '
./docs/conf.py:97:1: E265 block comment should start with '# '
./docs/conf.py:100:1: E265 block comment should start with '# '
./docs/conf.py:104:1: E265 block comment should start with '# '
./docs/conf.py:107:1: E265 block comment should start with '# '
./docs/conf.py:111:1: E265 block comment should start with '# '
./docs/conf.py:116:1: E265 block comment should start with '# '
./docs/conf.py:125:1: E265 block comment should start with '# '
./docs/conf.py:133:13: E241 multiple spaces after ':'
./docs/conf.py:134:10: E241 multiple spaces after ':'
./docs/conf.py:140:1: E265 block comment should start with '# '
./docs/conf.py:143:1: E265 block comment should start with '# '
./docs/conf.py:146:1: E265 block comment should start with '# '
./docs/conf.py:149:1: E265 block comment should start with '# '
./docs/conf.py:158:1: E265 block comment should start with '# '
./docs/conf.py:163:1: E265 block comment should start with '# '
./docs/conf.py:166:1: E265 block comment should start with '# '
./docs/conf.py:175:1: E265 block comment should start with '# '
./docs/conf.py:178:1: E265 block comment should start with '# '
./docs/conf.py:183:3: E121 continuation line under-indented for hanging indent
./docs/conf.py:190:17: E241 multiple spaces after ':'
./docs/conf.py:191:17: E241 multiple spaces after ':'
./docs/conf.py:197:1: E265 block comment should start with '# '
./docs/conf.py:201:1: E265 block comment should start with '# '
./docs/conf.py:204:1: E265 block comment should start with '# '
./docs/conf.py:207:1: E265 block comment should start with '# '
./docs/conf.py:210:1: E265 block comment should start with '# '
./docs/conf.py:213:1: E265 block comment should start with '# '
./docs/conf.py:216:1: E265 block comment should start with '# '
./src/tablib/__init__.py:3:1: F401 'tablib.core.Databook' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.Dataset' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.InvalidDatasetType' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.InvalidDimensions' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.UnsupportedFormat' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.detect_format' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.import_book' imported but unused
./src/tablib/__init__.py:3:1: F401 'tablib.core.import_set' imported but unused
./src/tablib/core.py:15:1: F401 'tablib.formats' imported but unused
./src/tablib/core.py:415:1: W293 blank line contains whitespace
./src/tablib/formats/_rst.py:66:13: E731 do not assign a lambda expression, use a def
./src/tablib/formats/_rst.py:68:13: E731 do not assign a lambda expression, use a def
./src/tablib/formats/_rst.py:70:13: E731 do not assign a lambda expression, use a def
./src/tablib/formats/_rst.py:89:5: E303 too many blank lines (2)
./src/tablib/formats/_rst.py:116:29: F821 undefined name '_get_column_widths'
./src/tablib/formats/_rst.py:188:5: E303 too many blank lines (2)
./src/tablib/formats/_ods.py:63:21: E266 too many leading '#' for block comment
./src/tablib/formats/_xls.py:67:5: E303 too many blank lines (2)
./src/tablib/formats/__init__.py:57:65: W291 trailing whitespace
./src/tablib/formats/_dbf.py:62:9: E265 block comment should start with '# '
./src/tablib/formats/_dbf.py:66:13: F841 local variable '_dbf' is assigned to but never used
./src/tablib/packages/dbfpy/dbfnew.py:27:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/dbfnew.py:27:1: F403 'from .dbf import *' used; unable to detect undefined names
./src/tablib/packages/dbfpy/dbfnew.py:28:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/dbfnew.py:28:1: F403 'from .fields import *' used; unable to detect undefined names
./src/tablib/packages/dbfpy/dbfnew.py:29:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/dbfnew.py:29:1: F403 'from .header import *' used; unable to detect undefined names
./src/tablib/packages/dbfpy/dbfnew.py:30:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/dbfnew.py:30:1: F403 'from .record import *' used; unable to detect undefined names
./src/tablib/packages/dbfpy/dbfnew.py:50:9: F405 'cls' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:51:15: F405 'DbfCharacterFieldDef' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:52:15: F405 'DbfNumericFieldDef' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:53:15: F405 'DbfLogicalFieldDef' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:56:15: F405 'DbfDateFieldDef' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:60:15: F405 'DbfDateTimeFieldDef' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:139:17: F405 'DbfHeader' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:158:12: F405 'Dbf' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:161:11: F405 'DbfRecord' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/dbfnew.py:167:11: F405 'DbfRecord' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
./src/tablib/packages/dbfpy/fields.py:33:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/fields.py:34:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/fields.py:35:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/fields.py:35:1: F401 'sys' imported but unused
./src/tablib/packages/dbfpy/fields.py:36:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/fields.py:38:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/fields.py:147:19: W504 line break after binary operator
./src/tablib/packages/dbfpy/fields.py:148:27: W504 line break after binary operator
./src/tablib/packages/dbfpy/fields.py:150:24: W504 line break after binary operator
./src/tablib/packages/dbfpy/fields.py:151:30: W504 line break after binary operator
./src/tablib/packages/dbfpy/fields.py:152:36: W504 line break after binary operator
./src/tablib/packages/dbfpy/header.py:22:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/header.py:23:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/header.py:24:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/header.py:25:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/header.py:27:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/header.py:28:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/dbf.py:65:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/dbf.py:66:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/utils.py:16:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/utils.py:17:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/record.py:19:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/record.py:21:1: E402 module level import not at top of file
./src/tablib/packages/dbfpy/record.py:85:69: E502 the backslash is redundant between brackets
./src/tablib/packages/dbfpy/record.py:104:49: W504 line break after binary operator
./src/tablib/packages/dbfpy/record.py:140:41: E225 missing whitespace around operator
./src/tablib/packages/dbfpy/record.py:227:12: E121 continuation line under-indented for hanging indent
./src/tablib/packages/dbfpy/record.py:228:13: E131 continuation line unaligned for hanging indent
2     E121 continuation line under-indented for hanging indent
1     E131 continuation line unaligned for hanging indent
1     E225 missing whitespace around operator
4     E241 multiple spaces after ':'
31    E265 block comment should start with '# '
1     E266 too many leading '#' for block comment
3     E303 too many blank lines (2)
21    E402 module level import not at top of file
1     E502 the backslash is redundant between brackets
4     E731 do not assign a lambda expression, use a def
10    F401 'tablib.core.Databook' imported but unused
4     F403 'from .dbf import *' used; unable to detect undefined names
10    F405 'cls' may be undefined, or defined from star imports: .dbf, .fields, .header, .record
1     F821 undefined name '_get_column_widths'
2     F841 local variable '_dbf' is assigned to but never used
1     W291 trailing whitespace
1     W293 blank line contains whitespace
7     W504 line break after binary operator
105

[hugovk]

But we can definitely skip Black if you're not keen on it.

It's not for everyone, and it's in no-one's interest if it in any way discourages you from maintaining Tablib.

[claudep]

Note that I'm happy to do the work of fixing flake8 errors myself. I just want to discuss some settings, like not limiting lines to 88 chars (Django uses 119 with satisfaction, but I'm fine with any number around 100).

[hugovk]

I'd rather not have it too big. Although modern screens/editors can easily fit 100-120 when editing code, one limiting factor is side-by-side diffs, where readability is just as important for reviews.

For example, on this laptop screen, GitHub's diff wraps at around 77 chars.

https://github.com/jazzband/tablib/pull/430/files#diff-d6e3b675c1b812304a6d688c5cd1eb58R101

https://github.com/jazzband/tablib/pull/430/files#diff-d6e3b675c1b812304a6d688c5cd1eb58R138

So I'd prefer it somewhere in the lower range of 88-100, if possible.

[hugovk]

Let's not worry about Black for now, it's not essential.