带有@deprecated 装饰器的函数的 lint 用法

Question

是否有一个 linter 可以检测被包中的@deprecated装饰器标记为已弃用的函数的使用情况deprecated？

例如在

from deprecated import deprecated

def realfun():
    print('Hey there')

@deprecated(reason="this is a test")
def myfun():
    realfun()

if __name__ == "__main__":
    myfun()

将它作为PYTHONWARNINGS="default::DeprecationWarning" python testfile.pybut pylint、mypy、运行时，我会收到运行时警告，并且flake8似乎（至少我如何运行它们）对调用myfun.

Answer 1

正如其他人所提到的，您必须编写一个自定义pylint检查器。它的工作方式是定义一个类，该类将pylint's子类化BaseChecker，并定义发出什么警告以及何时发出它们。

下面的代码正是这样做的。它有点适合deprecated包的特定关键字参数，但是当有人使用调用的装饰器deprecated来标记函数或类时，它应该可以正常工作，并且会发出pylint警告W0001（可以随意更改它，例如更改为错误）。它还应提供信息性消息。

要使用它，请将代码添加到名为 (for example)deprecated_checker.py的文件中，然后将包含的文件夹添加deprecated_checker.py到PYTHONPATH或将源添加到pylint/checkers文件夹中。然后你可以通过运行pylint选项来 lint --load-plugins=deprecated_checker。

有关编写自己的跳棋的更多信息，请查看此处。

from astroid.nodes import Call, ClassDef, FunctionDef, Name
from pylint.checkers import BaseChecker
from pylint.interfaces import IAstroidChecker


class DeprecatedChecker(BaseChecker):
    __implements__ = IAstroidChecker

    name = "no-deprecated"
    priority = -1
    msgs = {
        "W0001": (
            "%s %s is deprecated since version %s; reason: %s.",
            "deprecated",
            "Functions that have been marked via annotations as deprecated should not be used.",
        )
    }

    def __init__(self, linter=None):
        super().__init__(linter)

    def visit_decorators(self, node):
        # Check if there are decorators
        if node.nodes is None:
            return

        # Figure out whether its a class or function
        # that is deprecated, and get relevant info
        if isinstance(node.parent, ClassDef):
            parent_type = "Class"
        elif isinstance(node.parent, FunctionDef):
            parent_type = "Function"
        parent_name = node.parent.name

        # Check each decorator to see if its deprecating
        for decorator in node.get_children():
            if isinstance(decorator, Call):
                if decorator.func.name == "deprecated":
                    version = "(not specified)"
                    reason = "not specified"
                    if decorator.keywords is not None:
                        for kw in decorator.keywords:
                            if kw.arg == "version":
                                version = f'"{kw.value.value}"'
                            if kw.arg == "reason":
                                reason = f'"{kw.value.value}"'
                    self.add_message(
                        "deprecated",
                        node=node.parent,
                        args=(parent_type, parent_name, version, reason),
                    )
            elif isinstance(decorator, Name):
                if decorator.name == "deprecated":
                    self.add_message(
                        "deprecated",
                        node=node.parent,
                        args=(
                            parent_type,
                            parent_name,
                            "(not specified)",
                            "not specified",
                        ),
                    )

def register(linter):
    linter.register_checker(DeprecatedChecker(linter))

如果你已经完成了所有这些，那么 linting 存根文件 tmp.py

from deprecated import deprecated


@deprecated
def fn_stmt():
    pass

@deprecated(version="0.1.0")
def fn_version():
    pass

@deprecated(reason="I'm mean")
def fn_reason():
    pass

@deprecated(version="0.1.0", reason="I'm mean")
def fn_both():
    pass

@deprecated
class ClassStmt:
    pass

@deprecated(version="0.1.0")
class ClassVersion:
    pass

@deprecated(reason="I'm mean")
class ClassReason:
    pass

@deprecated(version="0.1.0", reason="I'm mean")
class ClassBoth:
    pass

用命令pylint --load-plugins=deprecated_checker --disable=all --enable=deprecated tmp.py会让你

************* Module tmp
tmp.py:5:0: W0001: Function fn_stmt is deprecated since version (not specified); reason: (not specified). (deprecated)
tmp.py:9:0: W0001: Function fn_version is deprecated since version 0.1.0; reason: (not specified). (deprecated)
tmp.py:13:0: W0001: Function fn_reason is deprecated since version (not specified); reason: I'm mean. (deprecated)
tmp.py:17:0: W0001: Function fn_both is deprecated since version 0.1.0; reason: I'm mean. (deprecated)
tmp.py:20:0: W0001: Class ClassStmt is deprecated since version (not specified); reason: (not specified). (deprecated)
tmp.py:24:0: W0001: Class ClassVersion is deprecated since version 0.1.0; reason: (not specified). (deprecated)
tmp.py:28:0: W0001: Class ClassReason is deprecated since version (not specified); reason: I'm mean. (deprecated)
tmp.py:32:0: W0001: Class ClassBoth is deprecated since version 0.1.0; reason: I'm mean. (deprecated)

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Your code has been rated at 5.29/10 (previous run: -2.35/10, +7.65)

Answer 2

您应该查看如何警告类（名称）弃用，以将您自己的规则添加到 lint。没有用于标记弃用的标准库方法，因此它不会内置到工具中。最接近的是图书馆中的特定课程warnings。