python：如何检查python文件/脚本的语法而不执行它？

Question

我曾经使用perl -c programfile来检查Perl程序的语法，然后退出而不执行它。对于 Python 脚本，是否有等效的方法来执行此操作？

Answer 1

您可以通过编译来检查语法：

python -m py_compile script.py

Answer 2

您可以使用以下工具：

• PyChecker
• Pyflakes
• Pylint

Answer 3

这是另一个使用 ast 模块的解决方案：

python -c "import ast; ast.parse(open('programfile').read())"

要从 Python 脚本中干净地完成此操作：

import ast, traceback

filename = 'programfile'
with open(filename) as f:
    source = f.read()
valid = True
try:
    ast.parse(source)
except SyntaxError:
    valid = False
    traceback.print_exc()  # Remove to silence any errros
print(valid)

Answer 4

import sys
filename = sys.argv[1]
source = open(filename, 'r').read() + '\n'
compile(source, filename, 'exec')

将其保存为 checker.py 并运行 python checker.py yourpyfile.py。

Answer 5

Pyflakes 按照你的要求做，它只是检查语法。来自文档：

Pyflakes 做出了一个简单的承诺：它永远不会抱怨风格，并且会非常非常努力地永远不会发出误报。

Pyflakes 也比 Pylint 或 Pychecker 更快。这很大程度上是因为 Pyflakes 仅单独检查每个文件的语法树。

安装和使用：

$ pip install pyflakes
$ pyflakes yourPyFile.py

Answer 6

python -m compileall -q .

将递归编译当前目录下的所有内容，并仅打印错误。

$ python -m compileall --help
usage: compileall.py [-h] [-l] [-r RECURSION] [-f] [-q] [-b] [-d DESTDIR] [-x REGEXP] [-i FILE] [-j WORKERS] [--invalidation-mode {checked-hash,timestamp,unchecked-hash}] [FILE|DIR [FILE|DIR ...]]

Utilities to support installing Python libraries.

positional arguments:
  FILE|DIR              zero or more file and directory names to compile; if no arguments given, defaults to the equivalent of -l sys.path

optional arguments:
  -h, --help            show this help message and exit
  -l                    don't recurse into subdirectories
  -r RECURSION          control the maximum recursion level. if `-l` and `-r` options are specified, then `-r` takes precedence.
  -f                    force rebuild even if timestamps are up to date
  -q                    output only error messages; -qq will suppress the error messages as well.
  -b                    use legacy (pre-PEP3147) compiled file locations
  -d DESTDIR            directory to prepend to file paths for use in compile-time tracebacks and in runtime tracebacks in cases where the source file is unavailable
  -x REGEXP             skip files matching the regular expression; the regexp is searched for in the full path of each file considered for compilation
  -i FILE               add all the files and directories listed in FILE to the list considered for compilation; if "-", names are read from stdin
  -j WORKERS, --workers WORKERS
                        Run compileall concurrently
  --invalidation-mode {checked-hash,timestamp,unchecked-hash}
                        set .pyc invalidation mode; defaults to "checked-hash" if the SOURCE_DATE_EPOCH environment variable is set, and "timestamp" otherwise.

当发现语法错误时，退出值为 1。

谢谢C2H5OH。

Answer 7

也许有用的在线检查器 PEP8 ： http://pep8online.com/

Answer 8

感谢上面的回答@Rosh Oxymoron。我改进了脚本以扫描目录中的所有 python 文件。所以对于我们这些懒人来说，只要给它目录，它就会扫描该目录中的所有 python 文件。您可以指定任何文件扩展名。你喜欢。

import sys
import glob, os

os.chdir(sys.argv[1])
for file in glob.glob("*.py"):
    source = open(file, 'r').read() + '\n'
    compile(source, file, 'exec')

将其保存为 checker.py 并运行 python checker.py ~/YOURDirectoryTOCHECK

Answer 9

由于某种原因（我是 py 新手...） -m 调用不起作用...

所以这里是一个 bash 包装函数...

# ---------------------------------------------------------
# check the python synax for all the *.py files under the
# <<product_version_dir/sfw/python
# ---------------------------------------------------------
doCheckPythonSyntax(){

    doLog "DEBUG START doCheckPythonSyntax"

    test -z "$sleep_interval" || sleep "$sleep_interval"
    cd $product_version_dir/sfw/python
    # python3 -m compileall "$product_version_dir/sfw/python"

    # foreach *.py file ...
    while read -r f ; do \

        py_name_ext=$(basename $f)
        py_name=${py_name_ext%.*}

        doLog "python3 -c \"import $py_name\""
        # doLog "python3 -m py_compile $f"

        python3 -c "import $py_name"
        # python3 -m py_compile "$f"
        test $! -ne 0 && sleep 5

    done < <(find "$product_version_dir/sfw/python" -type f -name "*.py")

    doLog "DEBUG STOP  doCheckPythonSyntax"
}
# eof func doCheckPythonSyntax