PylintDjango:AttributeError:“Subscript”对象没有属性“name”

Question

有一段时间我在用Pylint_django运行Pylint时遇到了一个问题。我包括了错误回溯和有关我的环境的详细信息

我想我已经找到了一个解决方案并提交了一个推送请求，但我在这里发布了这个问题，以防其他人面临同样的问题

该问题在GitHub中发布：https://github.com/PyCQA/pylint-django/issues/284

回溯：

Traceback (most recent call last):
  File "D:\DevTools\Python38-32\lib\runpy.py", line 193, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "D:\DevTools\Python38-32\lib\runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "D:\DevRepo\dex\venv\Scripts\pylint.exe\__main__.py", line 9, in <module>
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\__init__.py", line 22, in run_pylint
    PylintRun(sys.argv[1:])
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\lint\run.py", line 344, in __init__
    linter.check(args)
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\lint\pylinter.py", line 870, in check
    self._check_files(
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\lint\pylinter.py", line 904, in _check_files
    self._check_file(get_ast, check_astroid_module, name, filepath, modname)
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\lint\pylinter.py", line 930, in _check_file
    check_astroid_module(ast_node)
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\lint\pylinter.py", line 1062, in check_astroid_module 
    retval = self._check_astroid_module(
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\lint\pylinter.py", line 1107, in _check_astroid_module
    walker.walk(ast_node)
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\utils\ast_walker.py", line 75, in walk
    self.walk(child)
  File "d:\devrepo\dex\venv\lib\site-packages\pylint\utils\ast_walker.py", line 72, in walk
    callback(astroid)
  File "d:\devrepo\dex\venv\lib\site-packages\pylint_django\checkers\forms.py", line 47, in visit_classdef
    if child.targets[0].name == 'exclude':
AttributeError: 'Subscript' object has no attribute 'name'

在完全清理了文件forms.py之后，给出了错误，我想我已经成功地隔离了有问题的行。仍然给出错误的文件现在只包含以下内容：

from django import forms

from dex import models


class DataSelectionForm(forms.ModelForm):
    """
    Form
    """
    class Meta:
        model = models.DataSelection
        fields = [
            "field",
        ]
        widgets = {}
        widgets["field"] = forms.CheckboxSelectMultiple

当然，我已经过度简化了表单类。错误似乎是由widgets["field"] = forms.CheckboxSelectMultiple引起的，在实际代码中，它是在循环创建widgets dict之后向特定字段添加不同的widget

如果我改用widgets = {"field": forms.CheckboxSelectMultiple}，那么一切都很好

有关我的配置的一些详细信息：

• 操作系统：Windows 10 Pro x64
• Pip:19.2.3
• Python:3.8.2

pip冻结结果：

astroid==2.4.2
certifi==2020.6.20
chardet==3.0.4
colorama==0.4.3
Django==2.2.14
django-activity-stream==0.9.0
django-annoying==0.10.6
django-filter==2.3.0
django-formtools==2.2
django-jsonstore==0.4.1
django-material==1.6.7
django-simple-history==2.11.0
django-viewflow==1.6.1
docutils==0.16
gunicorn==20.0.4
idna==2.10
isort==4.3.21
lazy-object-proxy==1.4.3
mccabe==0.6.1
oauthlib==3.1.0
Pillow==7.2.0
psycopg2==2.8.5
pyasn1==0.4.8
pyasn1-modules==0.2.8
pylint==2.5.3
pylint-django==2.2.0
pylint-plugin-utils==0.6
python-ldap==3.3.1
python-magic==0.4.18
python-magic-bin==0.4.14
pytz==2020.1
PyYAML==5.3.1
requests==2.24.0
requests-oauthlib==1.3.0
rope==0.17.0
six==1.15.0
sqlparse==0.3.1
toml==0.10.1
urllib3==1.25.10
wrapt==1.12.1

Answer 1

虽然pylint_django不提供修复，但您可以通过避免类似widget["field"] = ...的赋值来解决此错误

我猜类似的代码，比如fields["field"] = "another_field_to_handle"会产生类似的问题

---

说明：

在深入研究了pylint_django的代码之后，我发现了以下内容：

meta.get_children()返回Meta类的所有子类，该类在示例代码中包含字典赋值

预期的子项为Assign类型，其属性目标中的第一项为AssignName类型，例如AssignName.widgets(name='widgets')

像widget["field"] = forms.SomeWidget这样的指令将导致Assign子级包含Subscript(ctx=<Context.Store: 2>, value=<Name.widgets ...>, slice=<Index ...>)。这当然出乎意料

我已经提交了一个推送请求，其中包含一个建议的修复：https://github.com/PyCQA/pylint-django/pull/285