Why does PyCharm use 120 Character Lines even though PEP8 Specifies 79?

python pycharm pep8
Samuel picture Samuel · Nov 7, 2014 · Viewed 29.3k times · Source

PEP8 clearly specifies 79 characters, however, PyCharm defaults to 120 and gives me the warning "PEP8: line too long (... > 120 characters)".

Did previous versions of PEP8 use 120 and PyCharm not update its PEP8 checker? I couldn't find any previous versions of the PEP8 Guide, however, I can easily find previous version of the PEP8 Python scripts.

I'm starting a new Python project and I'm not sure which to use.

References:

http://legacy.python.org/dev/peps/pep-0008/

Answer

munk picture munk · Nov 7, 2014

PyCharm is built on top of IntelliJ. IntelliJ has a default line length of 120 characters.

This is probably because you can't fit a common Java name like: @annotated public static MyObjectFactoryFactory enterpriseObjectFactoryFactoryBuilderPattern { in a mere 80 character line. (I'm poking fun, but Java names do tend to be longer by convention).

The pep8 checker is configurable, so you can specify a better max line length - like 79 characters.

The error is misleading because the pep8 checker formats the text with something like "PEP8: line too long(... > %s characters)" % max_line_setting. So it's using the pep8 checker, with a specific configuration, not claiming that pep8 specifies a 120 character line.

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