python pdb调试

在交互环境中通常使用pdb.run来调试：

import pdb

def pdb_test(arg):
    for i in range(arg):
        print(i)
    return arg

pdb.run("pdb_test(3)")

 b 函数名、行号：

     打断点，b可以查询所有的断点。

(Pdb) b pdb_test
Breakpoint 1 at c:usersplpccdesktoppdbtest.py:3
(Pdb) b
Num Type         Disp Enb   Where
1   breakpoint   keep yes   at c:usersplpccdesktoppdbtest.py:3

  c：

     运行程序，直到遇到断点。

(Pdb) c
> c:usersplpccdesktoppdbtest.py(4)pdb_test()
-> for i in range(arg):

   l：

     查看断点周围的代码

(Pdb) l
  1  	import pdb
  2  	
  3 B	def pdb_test(arg):
  4  ->	    for i in range(arg):
  5  	        print(i)
  6  	    return arg
  7  	
  8  	pdb.run("pdb_test(3)")

  a:

     查看参数

(Pdb) a
arg = 3

  s, n：

     单步运行,区别s会进入路径中的函数，n不会进入 

  p：

     查看表达式的值

(Pdb) p i
0

  condition：

     条件断点，只有条件为true断点才命中

> c:usersplpccdesktoppdbtest.py(5)pdb_test()
-> print(i)
(Pdb) l
  1  	import pdb
  2  	
  3  	def pdb_test(arg):
  4  	    for i in range(arg):
  5 B->	        print(i)
  6  	    return arg
  7  	
  8  	pdb.run("pdb_test(3)")
[EOF]
(Pdb) b
Num Type         Disp Enb   Where
2   breakpoint   keep yes   at c:usersplpccdesktoppdbtest.py:5
(Pdb) condition 2 i==1   //i==1时才触发断点2
New condition set for breakpoint 2.
(Pdb) b
Num Type         Disp Enb   Where
2   breakpoint   keep yes   at c:usersplpccdesktoppdbtest.py:5
	stop only if i==1
(Pdb) c
0                       //i==0直接打印未断住
> c:usersplpccdesktoppdbtest.py(5)pdb_test()
-> print(i)             //触发断点，i==1
(Pdb) p i
1

  bt:

      查看调用堆栈

(Pdb) bt
  c:python33libdb.py(405)run()
-> exec(cmd, globals, locals)
  <string>(1)<module>()
> c:usersplpccdesktoppdbtest.py(5)pdb_test()
-> print(i)

  r：

      执行到函数返回

(Pdb) r
1
2
--Return--
> c:usersplpccdesktoppdbtest.py(6)pdb_test()->3 //代码位置、函数返回值->3
-> return arg                                       //代码位置的语句
(Pdb) l
  1  	import pdb
  2  	
  3  	def pdb_test(arg):
  4  	    for i in range(arg):
  5  	        print(i)
  6  ->	    return arg
  7  	
  8  	pdb.run("pdb_test(3)")

通过pdb.set_trace() 在代码中指定位置嵌入一个断点，通常可以通过调试开关来控制

import pdb

__DEBUG__ = True

def pdb_test(arg):
    if True == __DEBUG__:
        pdb.set_trace()
    for i in range(arg):
        print(i)
    return arg

pdb_test(3)

 运行后在pdb.set_trace()位置被断住，当__DEBUG__ = False，代码正常运行

> c:usersplpccdesktoppdbtest.py(8)pdb_test()
-> for i in range(arg):
(Pdb) l
  3  	__DEBUG__ = True
  4  	
  5  	def pdb_test(arg):
  6  	    if True == __DEBUG__:
  7  	        pdb.set_trace()
  8  ->	    for i in range(arg):
  9  	        print(i)
 10  	    return arg
 11  	
 12  	pdb_test(3)
[EOF]

通过pdb.pm()进行事后调试，可以跟踪异常程序最后的堆载信息：

Traceback (most recent call last):
  File "C:UsersplpccDesktoppdbTest.py", line 13, in <module>
    pdb_test(3)
  File "C:UsersplpccDesktoppdbTest.py", line 10, in pdb_test
    1/0
ZeroDivisionError: division by zero
>>> import pdb
>>> pdb.pm()
> c:usersplpccdesktoppdbtest.py(10)pdb_test()
-> 1/0
(Pdb) l
  5  	def pdb_test(arg):
  6  	    if True == __DEBUG__:
  7  	        pdb.set_trace()
  8  	    for i in range(arg):
  9  	        print(i)
 10  ->	        1/0
 11  	    return arg
 12  	
 13  	pdb_test(3)