I’m using flake8 in Visual Studio Code, writing some code using Python 3.6 variable annotations. It worked without any problems so far, but I encountered a strange warning.
This works fine:
style: str = """
width: 100%;
...
"""
# Doing sth with `style`
This too:
img_style: str = """
width: 100%;
...
"""
# Doing sth with `img_style`
This however does not, it yields below warning:
iframe_style: str = """
width: 100%;
...
"""
# Doing sth with `iframe_style`
Well, technically it does work fine; the code runs. But somehow flake8 is not happy with this.
The multiline string and the code following is always the same.
When I omit the «f» (i_rame_style), I don’t get a warning, too! So I guess for some reason flake8 thinks of a if foo: bar() here!?
What am I missing here? Is this a bug in flake8?
asked Apr 11, 2018 at 11:50
linusglinusg
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Edit: The problem is in pycodestyle (pep8), which is called by flake8. The rest still stands.
Second edit: I’ve made some more research and the issue is fixed here. The fix hasn’t been released yet, though.
Definitely looks like a flake8 bug to me:
flakebug.py:
innocuous: str = ""
ifstarting_string: str = ""
forfalse_positivetoo: str = ""
whilethis_lookslikeabug: str = ""
elsehaha: str = ""
In the shell:
$ # python3.6 -m pycodestyle flakebug.py gives the same results
$ python3.6 -m flake8 flakebug.py
flakebug.py:2:18: E701 multiple statements on one line (colon)
flakebug.py:3:21: E701 multiple statements on one line (colon)
flakebug.py:4:24: E701 multiple statements on one line (colon)
flakebug.py:5:9: E701 multiple statements on one line (colon)
Looks like every line starting with a control flow statement triggers it.
I’d wager it uses a regex like (if|else|while|for).*:.
I’ll try to get to the bottom of this and update this answer if I can, meanwhile you could add some # noqa annotations and you’ll be set 
answered Apr 11, 2018 at 12:07
eteneetene
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Jun 9, 2017
If a Python 3 class variable begins with an indent keyword, i.e.,
class Class:
with_foo: int
pycodestyle will erroneously output the error 'E701 multiple statements
on one line'. This patch tightens the check so that even variables
beginning with indent keywords are allowed.
Resolves PyCQA#635
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With a new version of flake8 we can now stop ignoring E701 that was introduced to this bug: PyCQA/pycodestyle#635
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With a new version of flake8 we can now stop ignoring E701 that was introduced to this bug: PyCQA/pycodestyle#635
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With a new version of flake8 we can now stop ignoring E701 that was introduced to this bug: PyCQA/pycodestyle#635
Я использую flake8 в Visual Studio Code, пишу код с помощью Аннотации переменных Python 3.6. Пока все работало без проблем, но я столкнулся со странным предупреждением.
Это отлично работает:
style: str = """
width: 100%;
...
"""
# Doing sth with `style`
Это тоже:
img_style: str = """
width: 100%;
...
"""
# Doing sth with `img_style`
Однако это не так, это приводит к предупреждению ниже:
iframe_style: str = """
width: 100%;
...
"""
# Doing sth with `iframe_style`
Что ж, технически это работает нормально; код работает. Но почему-то flake8 это не устраивает. Многострочная строка и следующий за ней код всегда одинаковы.
Когда я опускаю букву «f» (i_rame_style), я тоже не получаю предупреждения! Так что, я думаю, по какой-то причине flake8 думает о if foo: bar() здесь !?
Что мне здесь не хватает? Это ошибка в flake8?
1 ответ
Лучший ответ
Изменить: проблема в pycodestyle (pep8), который вызывается flake8. Остальные по-прежнему в силе.
Второе изменение: я провел дополнительное исследование, и проблема исправлена здесь. Однако исправление еще не выпущено.
Для меня это определенно похоже на ошибку flake8:
flakebug.py:
innocuous: str = ""
ifstarting_string: str = ""
forfalse_positivetoo: str = ""
whilethis_lookslikeabug: str = ""
elsehaha: str = ""
В оболочке:
$ # python3.6 -m pycodestyle flakebug.py gives the same results
$ python3.6 -m flake8 flakebug.py
flakebug.py:2:18: E701 multiple statements on one line (colon)
flakebug.py:3:21: E701 multiple statements on one line (colon)
flakebug.py:4:24: E701 multiple statements on one line (colon)
flakebug.py:5:9: E701 multiple statements on one line (colon)
Похоже, что каждая строка, начинающаяся с оператора потока управления, запускает его. Держу пари, что здесь используется регулярное выражение вроде (if|else|while|for).*:.
Я постараюсь разобраться в этом и обновить этот ответ, если смогу, а пока вы можете добавить несколько аннотаций # noqa, и все будет готово
10
etene
11 Апр 2018 в 15:26