出于调试目的,我想打印出与 python 方法中执行的每一行相关的内容。
例如,如果该行中有一些赋值,我想打印为该变量分配的值,如果有函数调用,我想打印出函数返回的值,等等。
所以,例如,如果我要使用装饰器,应用于函数/方法,例如:
@some_decorator
def testing() :
a = 10
b = 20
c = a + b
e = test_function()
调用函数测试时,应打印以下内容:
a = 10
b = 20
c = 30
e = some_value
有什么方法可以实现这一点吗?更根本的是,我想知道我是否可以编写一段代码,可以逐行遍历其他代码,检查它是什么类型的指令,等等。或者也许我们可以得到一个字典来找出所有变量一个类,我可以得到一个类似数据结构的字典来获取函数中的每条指令,这与元程序一样好。
因此,我特别寻找一种使用装饰器的解决方案,因为我很好奇是否可以有一个装饰器可以逐行遍历整个函数,并逐行装饰它, 但任何和所有解决方案都是受欢迎的。
提前致谢。
这样的事情怎么样?这对你有用吗?
调试上下文:
import sys
class debug_context():
""" Debug context to trace any function calls inside the context """
def __init__(self, name):
self.name = name
def __enter__(self):
print('Entering Debug Decorated func')
# Set the trace function to the trace_calls function
# So all events are now traced
sys.settrace(self.trace_calls)
def __exit__(self, *args, **kwargs):
# Stop tracing all events
sys.settrace = None
def trace_calls(self, frame, event, arg):
# We want to only trace our call to the decorated function
if event != 'call':
return
elif frame.f_code.co_name != self.name:
return
# return the trace function to use when you go into that
# function call
return self.trace_lines
def trace_lines(self, frame, event, arg):
# If you want to print local variables each line
# keep the check for the event 'line'
# If you want to print local variables only on return
# check only for the 'return' event
if event not in ['line', 'return']:
return
co = frame.f_code
func_name = co.co_name
line_no = frame.f_lineno
filename = co.co_filename
local_vars = frame.f_locals
print (' {0} {1} {2} locals: {3}'.format(func_name,
event,
line_no,
local_vars))
调试装饰器:
def debug_decorator(func):
""" Debug decorator to call the function within the debug context """
def decorated_func(*args, **kwargs):
with debug_context(func.__name__):
return_value = func(*args, **kwargs)
return return_value
return decorated_func
使用方法
@debug_decorator
def testing() :
a = 10
b = 20
c = a + b
testing()
输出
###########################################################
#output:
# Entering Debug Decorated func
# testing line 44 locals: {}
# testing line 45 locals: {'a': 10}
# testing line 46 locals: {'a': 10, 'b': 20}
# testing return 46 locals: {'a': 10, 'b': 20, 'c': 30}
###########################################################
如果添加:
...
co = frame.f_code
if self.filename is None:
self.filename = co.co_filename
cur_filename = co.co_filename
if cur_filename == self.filename:
...
到
def trace_line
您可以继续仅跟踪当前文件