Debugging

Example of history call

a = 1

b = 2

assert a+b == 3

How to debug last call

Single step

Step-by-step

Get underlying CellProcessor object

c = %cell_processor

If we already called the magic function, we can get access to the call history as follows:

c.call_history

[('first_data --test --data', 'a = 1\n'),
 ('second_data --test --data', 'b = 2\n'),
 ('first_test --test', 'assert a+b == 3\n')]

We need to reset the cell_processor to erase local variables:

c.reset()

If we don’t have called the magic function before, we won’t have a call history, but we just can indicate it.

c.call_history = [('first_data --test --data', 'a = 1\n'),
 ('second_data --test --data', 'b = 2\n'),
 ('first_test --test', 'assert a+b == 3\n')]

Now we simulate the calls until the point that we want to debug:

for call in c.call_history[:2]:
    c.process_function_call (*call, add_call=False)

We import the ipdb debugger and make the call that we want to debug. In this example, this call is the one in position 2 in the call_history

import ipdb

ipdb.runcall (c.process_function_call, *c.call_history[2], add_call=False)

> /home/jaumeamllo/workspace/mine/nbmodular/nbmodular/core/cell2func.py(316)process_function_call()
    315     def process_function_call (self, line, cell, add_call=True):
--> 316         call = (line, cell)
    317         if add_call:

ipdb>  q

How to debug a single cell