exceptions in ipython sphinx directive not reported

[ibell]

Exceptions in an ipython sphinx directive, something like

.. ipython::

    In [0]: throw ValueError()

are not output to the shell when the sphinx build happens, but now are silently ignored, though the traceback is written out to the output in HTML/PDF...:

In [1]: throw ValueError()
  File "<ipython-input-1-af7bbb4db1fc>", line 1
    throw ValueError()
                   ^
SyntaxError: invalid syntax

If an exception occurs in an imported module, the full traceback is shown in the sphinx build log. It would be better if there was at least a warning in the sphinx build to let you know that there was a problem in the build, otherwise you have to look at each output page to find errors

[ibell]

Nothing is printed to stdout because there is no "Traceback" in the output, as you can see from this block in the code (https://github.com/ipython/ipython/blob/master/IPython/sphinxext/ipython_directive.py#L506-L512) :

if not is_okexcept and "Traceback" in processed_output:
            s =  "\nException in %s at block ending on line %s\n" % (filename, lineno)
            s += "Specify :okexcept: as an option in the ipython:: block to suppress this message\n"
            sys.stdout.write('\n\n>>>' + ('-' * 73))
            sys.stdout.write(s)
            sys.stdout.write(processed_output)
            sys.stdout.write('<<<' + ('-' * 73) + '\n\n')

[ibell]

Not sure how best to handle this elegantly....

[jorisvandenbossche]

Is SyntaxError the only error that does not have a Traceback?
In that case you could easily change the Traceback check to

and ("Traceback" in processed_output or "SyntaxError" in processed_output):