Python - 使用Pylint检查分析代码

1-简介

Home Page : https://www.pylint.org/

• 检查语法错误，是否遵守编码风格标准、潜在的问题等；
• 支持自定义配置：例如显示或隐藏特定的警告，并且可以通过编写插件来添加功能；
• 使用Pylint检查文件时，需要直接将模块或包名作为参数；
• 可以在命令行以脚本方式运行（pylint），也可作为模块（pylint.lint）导入，建议作为命令行工具使用；

 

2-帮助信息

帮助信息：

• 在命令行下运行“pylint -h”或“pylint --help”获取帮助信息；

常用命令行参数：

--generate-rcfile
生成一个配置文件示例；
可以使用重定向把这个配置文件保存下来用做以后使用；
也可以在前面加上其它选项，使这些选项的值被包含在这个产生的配置文件里；
如：“pylint --persistent=n --generate-rcfile > pylint.conf”，查看 pylint.conf，可以看到 persistent=no，而不再是其默认值 yes；

--rcfile=<file>
指定一个配置文件；
把使用的配置放在配置文件中，这样不仅规范了自己代码，也可以方便地和别人共享这些规范；

-i <y_or_n>, --include-ids=<y_or_n>
在输出中包含 message 的 id, 然后通过“pylint --help-msg=<msg-id>”来查看这个错误的详细信息，这样可以具体地定位错误。

-r <y_or_n>, --reports=<y_or_n>
表示 Pylint 的输出中是否包含报告部分；

--files-output=<y_or_n>
将每个 module /package 的 message 输出到一个以 pylint_module/package. [txt|html] 命名的文件中；
如果有 report 的话，输出到名为 pylint_global.[txt|html] 的文件中。默认是输出到屏幕上不输出到文件里；

-f <format>, --output-format=<format>
设置输出格式；
可以选择的格式有 text, parseable, colorized, msvs (visual studio) 和 html, 默认的输出格式是 text；

--disable-msg=<msg ids>
禁止指定 id 的 message；
例如：输出中包含了 W0402 这个 warning 的 message, 如果不希望它在输出中出现，可以使用“--disable-msg= W0402”；

3-安装

$ pip3 show pylint
Name: pylint
Version: 2.1.
Summary: python code static checker
Home-page: https://github.com/PyCQA/pylint
Author: Python Code Quality Authority
Author-email: code-quality@python.org
License: GPL
Location: c:\python36\lib\site-packages
Requires: colorama, isort, astroid, mccabe
Required-by:

$ py --version
Python 3.6.

$ py -m pylint --version
__main__.py 2.1.
astroid 2.0.
Python 3.6. (v3.6.0:41df79263a11, Dec  , ::) [MSC v.  bit (AMD64)]

生成默认配置文件：将在当前目录生成pylint.conf文件，包含pylint的默认配置项；

$ py -m pylint --persistent=n --generate-rcfile > pylint.conf

$ ll -h pylint.conf
-rw-r--r--  guowli  18K Nov  : pylint.conf

4-检查单个文件（模块）

$ cat test.py
import time

def shwotime():
    print(time.asctime())

shwotime()

$ py -m pylint --rcfile=pylint.conf test.py
************* Module test
test.py::: C0111: Missing module docstring (missing-docstring)
test.py::: C0111: Missing function docstring (missing-docstring)

-----------------------------------
Your code has been rated at 5.00/

$ py -m pylint -ry --rcfile=pylint.conf test.py
************* Module test
test.py::: C0111: Missing module docstring (missing-docstring)
test.py::: C0111: Missing function docstring (missing-docstring)

Report
======
 statements analysed.

Statistics by type
------------------

+---------+-------+-----------+-----------+------------+---------+
|type     |number |old number |difference |%documented |%badname |
+=========+=======+===========+===========+============+=========+
|module   |      |NC         |NC         |0.00        |0.00     |
+---------+-------+-----------+-----------+------------+---------+
|class    |      |NC         |NC         |           |        |
+---------+-------+-----------+-----------+------------+---------+
|method   |      |NC         |NC         |           |        |
+---------+-------+-----------+-----------+------------+---------+
|function |      |NC         |NC         |0.00        |0.00     |
+---------+-------+-----------+-----------+------------+---------+

Raw metrics
-----------

+----------+-------+------+---------+-----------+
|type      |number |%     |previous |difference |
+==========+=======+======+=========+===========+
|code      |      |50.00 |NC       |NC         |
+----------+-------+------+---------+-----------+
|docstring |      |0.00  |NC       |NC         |
+----------+-------+------+---------+-----------+
|comment   |      |0.00  |NC       |NC         |
+----------+-------+------+---------+-----------+
|empty     |      |50.00 |NC       |NC         |
+----------+-------+------+---------+-----------+

Duplication
-----------

+-------------------------+------+---------+-----------+
|                         |now   |previous |difference |
+=========================+======+=========+===========+
|nb duplicated lines      |     |NC       |NC         |
+-------------------------+------+---------+-----------+
|percent duplicated lines |0.000 |NC       |NC         |
+-------------------------+------+---------+-----------+

Messages by category
--------------------

+-----------+-------+---------+-----------+
|type       |number |previous |difference |
+===========+=======+=========+===========+
|convention |      |NC       |NC         |
+-----------+-------+---------+-----------+
|refactor   |      |NC       |NC         |
+-----------+-------+---------+-----------+
|warning    |      |NC       |NC         |
+-----------+-------+---------+-----------+
|error      |      |NC       |NC         |
+-----------+-------+---------+-----------+

Messages
--------

+------------------+------------+
|message id        |occurrences |
+==================+============+
|missing-docstring |           |
+------------------+------------+

-----------------------------------
Your code has been rated at 5.00/

结果说明：

• Pylint结果的级别：error，warning，refactor，convention；
• 可以根据首字母确定相应的级别，例如，C表示convention（规范）、W表示warning（告警）；
• 级别之后的数字表示告警所在文件中的行号和列号；
• 参数 “-ry”开启报告，“-rn”关闭报告（只显示警告和错误），默认为关闭报告；

5-检查整个工程

在工程根目录下添加init.py文件，即把工程当做一个python包，可以对整个工程进行pylint；

$ ll -Ri testproject/
testproject/:
total
  -rw-r--r--  guowli     Sep  : __init__.py
  -rw-r--r--  guowli   Sep  : Chapter06_Modules.py
  -rw-r--r--  guowli   Sep  : Chapter06_ModuleTest.py
 drwxr-xr-x  guowli      Nov  : TestPackage/

testproject/TestPackage:
total
  -rw-r--r--  guowli    Sep  : __init__.py
 -rw-r--r--  guowli   Sep  : ModuleTest.py

$ py -m pylint --rcfile=pylint.conf testproject/
************* Module testproject.Chapter06_Modules
testproject\Chapter06_Modules.py::: C0103: Module name "Chapter06_Modules" doesn't conform to snake_case naming style (invalid-name)
testproject\Chapter06_Modules.py::: C0111: Missing module docstring (missing-docstring)
testproject\Chapter06_Modules.py::: E0401: Unable to import 'Chapter06_ModuleTest' (import-error)
testproject\Chapter06_Modules.py::: E0401: Unable to import 'TestPackage' (import-error)
testproject\Chapter06_Modules.py::: E0401: Unable to import 'TestPackage.ModuleTest' (import-error)
testproject\Chapter06_Modules.py::: C0103: Constant name "mp" doesn't conform to UPPER_CASE naming style (invalid-name)
testproject\Chapter06_Modules.py::: C0411: standard import "import os" should be placed before "import Chapter06_ModuleTest as cMT" (wrong-import-order)
testproject\Chapter06_Modules.py::: C0411: standard import "import pprint" should be placed before "import Chapter06_ModuleTest as cMT" (wrong-import-order)
************* Module testproject.Chapter06_ModuleTest
testproject\Chapter06_ModuleTest.py::: C0103: Module name "Chapter06_ModuleTest" doesn't conform to snake_case naming style (invalid-name)
testproject\Chapter06_ModuleTest.py::: C0111: Missing module docstring (missing-docstring)
testproject\Chapter06_ModuleTest.py::: C0111: Missing function docstring (missing-docstring)
testproject\Chapter06_ModuleTest.py::: C0111: Missing function docstring (missing-docstring)
testproject\Chapter06_ModuleTest.py::: R1705: Unnecessary "else" after "return" (no-else-return)
************* Module testproject.TestPackage.ModuleTest
testproject\TestPackage\ModuleTest.py::: C0103: Module name "ModuleTest" doesn't conform to snake_case naming style (invalid-name)
testproject\TestPackage\ModuleTest.py::: C0111: Missing module docstring (missing-docstring)
testproject\TestPackage\ModuleTest.py::: C0111: Missing function docstring (missing-docstring)
************* Module testproject.TestPackage
testproject\TestPackage\__init__.py::: C0103: Module name "TestPackage" doesn't conform to snake_case naming style (invalid-name)
testproject\TestPackage\__init__.py::: C0111: Missing module docstring (missing-docstring)

-----------------------------------
Your code has been rated at 3.18/

6-集成到PyCharm

File --》Settings --》Tools --》External Tools

保存并应用后，Tools菜单下将会显示pylint工具选项；

如果想要pylint当前文件，只需要点击此选项即可；

7-其他工具

pycodestyle

• 根据PEP8中的某些样式约定来检查Python代码的工具
• https://pypi.org/project/pycodestyle/
• 使用pip安装pycodestyle：pip install pycodestyle
• 从终端运行pycodestyle：pycodestyle code.py

flake8

• 结合了pyflakes和pycodestyle的工具
• https://pypi.org/project/flake8/
• 使用pip安装flake8：pip install flake8
• 从终端运行flake8：flake8 code.py