after continue, Pdb stops at a line without a breakpoint

[xdegaye]

BPO	14789
Nosy	@birkenfeld, @xdegaye
Files	pdb_default.patch

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2012-05-12.13:54:11.999>
labels = ['type-bug', 'library']
title = 'after continue, Pdb stops at a line without a breakpoint'
updated_at = <Date 2012-05-25.11:54:29.370>
user = 'https://github.com/xdegaye'

bugs.python.org fields:

activity = <Date 2012-05-25.11:54:29.370>
actor = 'xdegaye'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2012-05-12.13:54:11.999>
creator = 'xdegaye'
dependencies = []
files = ['25549']
hgrepos = []
issue_num = 14789
keywords = ['patch']
message_count = 2.0
messages = ['160470', '161571']
nosy_count = 2.0
nosy_names = ['georg.brandl', 'xdegaye']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue14789'
versions = ['Python 2.7', 'Python 3.2', 'Python 3.3']

[xdegaye]

In the following test run with python on the current head of the
default branch, Pdb stops at line 3 where there is no breakpoint after
two breakpoints have been set on the same function (setting two bps on
the same location is useful, for example one bp to print a value without
stopping and the other one with an ignore count).

=== main.py =================================

def bar():
    x = 1
    x = 2

bar()

=================================================

$ python -m pdb main.py 
> /path_to/main.py(1)<module>()
-> def bar():
(Pdb) import sys; print(sys.version)
3.3.0a3+ (default:4e9680570be8, May 11 2012, 12:09:15) 
[GCC 4.3.2]
(Pdb) break bar
Breakpoint 1 at /path_to/main.py:1
(Pdb) break bar
Breakpoint 2 at /path_to/main.py:1
(Pdb) continue
> /path_to/main.py(2)bar()
-> x = 1
(Pdb) continue
> /path_to/main.py(3)bar()
-> x = 2
(Pdb) quit

=================================================

The attached patch fixes the problem. This patch also fixes the
following problems that are caused by the same bug:

* when more than one breakpoint is set on the same line, only the
  command of the first effective breakpoint is run, and only the
  hit count and the ignore count of the first effective breakpoint
  are updated

The patch includes a test case for all those problems.

[xdegaye]

Parsing the modules source seems a better way to fix this problem, see bpo-14913.

[gaogaotiantian]

Now that the breakpoint is parsed better, this issue does not appear anymore. Close.