Tracebacks please!

[Jeroen Demeyer]

Hello all Sage developers,

I am getting more and more annoyed that many people tend to report bugs
(both on Trac and on the mailing list) *without* tracebacks.

Those tracebacks are often crucial information to fix a bug. For a
totally reproducible and deterministic bug, this isn't so bad since I
can always run the code myself and see what happens.

But for errors that I cannot reproduce, the traceback is what I need to
understand what is going wrong.

So, please remember: the next time you report a bug, do include the
*full* output that you get.

[Maarten Derickx]

I want to add to this that including both your operation system and sage version are also very useful in this respect (and sometimes even your processor type).

[Fernando Perez]

On Thu, Oct 5, 2017 at 5:43 AM, Maarten Derickx <m.derick...@gmail.com> wrote:

I want to add to this that including both your operation system and sage version are also very useful in this respect (and sometimes even your processor type).

Couple quick tips:

1. IPython's `%xmode verbose` automatically gives extra detailed tracebacks that are particularly useful for this:

In [25]: x=0

In [26]: y=1

In [27]: y/x

---------------------------------------------------------------------------

ZeroDivisionError                         Traceback (most recent call last)

<ipython-input-27-d2d3fa2acc3f> in <module>()

----> 1 y/x

ZeroDivisionError: division by zero

In [28]: %xmode verbose

Exception reporting mode: Verbose

In [29]: y/x

---------------------------------------------------------------------------

ZeroDivisionError                         Traceback (most recent call last)

<ipython-input-29-d2d3fa2acc3f> in <module>()

----> 1 y/x

        global y = 1

        global x = 0

ZeroDivisionError: division by zero

2. IPython's sys_info() prints system details:

In [20]: from IPython import sys_info

In [21]: print(sys_info())

{'commit_hash': '36ab971de',

 'commit_source': 'repository',

 'default_encoding': 'UTF-8',

 'ipython_path': '/Users/fperez/dev/ipython/ipython/IPython',

 'ipython_version': '6.2.0.dev',

 'os_name': 'posix',

 'platform': 'Darwin-16.7.0-x86_64-i386-64bit',

 'sys_executable': '/Users/fperez/usr/conda/bin/python',

 'sys_platform': 'darwin',

 'sys_version': '3.6.2 |Anaconda, Inc.| (default, Oct  5 2017, 03:00:07) \n'

                '[GCC 4.2.1 Compatible Clang 4.0.1 (tags/RELEASE_401/final)]'}

In fact, IPython's crash handler (its internal sys.excepthook) consists more or less of a traceback made with verbose mode + the output of sys_info, and it can be very handy.

Cheers,

f