##// END OF EJS Templates
Reset the interactive namespace __warningregistry__ before executing code...
Reset the interactive namespace __warningregistry__ before executing code Fixes #6611. Idea: Right now, people often don't see important warnings when running code in IPython, because (to a first approximation) any given warning will only issue once per session. Blink and you'll miss it! This is a very common contributor to confused emails to numpy-discussion. E.g.: In [5]: 1 / my_array_with_random_contents /home/njs/.user-python2.7-64bit-3/bin/ipython:1: RuntimeWarning: divide by zero encountered in divide #!/home/njs/.user-python2.7-64bit-3/bin/python Out[5]: array([ 1.77073316, -2.29765021, -2.01800811, ..., 1.13871243, -1.08302964, -8.6185091 ]) Oo, right, guess I gotta be careful of those zeros -- thanks, numpy, for giving me that warning! A few days later: In [592]: 1 / some_other_array Out[592]: array([ 3.07735763, 0.50769289, 0.83984078, ..., -0.67563917, -0.85736257, -1.36511271]) Oops, it turns out that this array had a zero in it too, and that's going to bite me later. But no warning this time! The effect of this commit is to make it so that warnings triggered by the code in cell 5 do *not* suppress warnings triggered by the code in cell 592. Note that this only applies to warnings triggered *directly* by code entered interactively -- if somepkg.foo() calls anotherpkg.bad_func() which issues a warning, then this warning will still only be displayed once, even if multiple cells call somepkg.foo(). But if cell 5 and cell 592 both call anotherpkg.bad_func() directly, then both will get warnings. (Important exception: if foo() is defined *interactively*, and calls anotherpkg.bad_func(), then every cell that calls foo() will display the warning again. This is unavoidable without fixes to CPython upstream.) Explanation: Python's warning system has some weird quirks. By default, it tries to suppress duplicate warnings, where "duplicate" means the same warning message triggered twice by the same line of code. This requires determining which line of code is responsible for triggering a warning, and this is controlled by the stacklevel= argument to warnings.warn. Basically, though, the idea is that if foo() calls bar() which calls baz() which calls some_deprecated_api(), then baz() will get counted as being "responsible", and the warning system will make a note that the usage of some_deprecated_api() inside baz() has already been warned about and doesn't need to be warned about again. So far so good. To accomplish this, obviously, there has to be a record of somewhere which line this was. You might think that this would be done by recording the filename:linenumber pair in a dict inside the warnings module, or something like that. You would be wrong. What actually happens is that the warnings module will use stack introspection to reach into baz()'s execution environment, create a global (module-level) variable there named __warningregistry__, and then, inside this dictionary, record just the line number. Basically, it assumes that any given module contains only one line 1, only one line 2, etc., so storing the filename is irrelevant. Obviously for interactive code this is totally wrong -- all cells share the same execution environment and global namespace, and they all contain a new line 1. Currently the warnings module treats these as if they were all the same line. In fact they are not the same line; once we have executed a given chunk of code, we will never see those particular lines again. As soon as a given chunk of code finishes executing, its line number labels become meaningless, and the corresponding warning registry entries become meaningless as well. Therefore, with this patch we delete the __warningregistry__ each time we execute a new block of code.

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export.py
174 lines | 5.3 KiB | text/x-python | PythonLexer
"""Module containing single call export functions."""
# Copyright (c) IPython Development Team.
# Distributed under the terms of the Modified BSD License.
from functools import wraps
from IPython.nbformat.v3.nbbase import NotebookNode
from IPython.utils.decorators import undoc
from IPython.utils.py3compat import string_types
from .exporter import Exporter
from .templateexporter import TemplateExporter
from .html import HTMLExporter
from .slides import SlidesExporter
from .latex import LatexExporter
from .pdf import PDFExporter
from .markdown import MarkdownExporter
from .python import PythonExporter
from .rst import RSTExporter
from .notebook import NotebookExporter
#-----------------------------------------------------------------------------
# Classes
#-----------------------------------------------------------------------------
@undoc
def DocDecorator(f):
#Set docstring of function
f.__doc__ = f.__doc__ + """
nb : :class:`~{nbnode_mod}.NotebookNode`
The notebook to export.
config : config (optional, keyword arg)
User configuration instance.
resources : dict (optional, keyword arg)
Resources used in the conversion process.
Returns
-------
tuple- output, resources, exporter_instance
output : str
Jinja 2 output. This is the resulting converted notebook.
resources : dictionary
Dictionary of resources used prior to and during the conversion
process.
exporter_instance : Exporter
Instance of the Exporter class used to export the document. Useful
to caller because it provides a 'file_extension' property which
specifies what extension the output should be saved as.
Notes
-----
WARNING: API WILL CHANGE IN FUTURE RELEASES OF NBCONVERT
""".format(nbnode_mod=NotebookNode.__module__)
@wraps(f)
def decorator(*args, **kwargs):
return f(*args, **kwargs)
return decorator
#-----------------------------------------------------------------------------
# Functions
#-----------------------------------------------------------------------------
__all__ = [
'export',
'export_html',
'export_custom',
'export_slides',
'export_latex',
'export_pdf',
'export_markdown',
'export_python',
'export_rst',
'export_by_name',
'get_export_names',
'ExporterNameError'
]
class ExporterNameError(NameError):
pass
@DocDecorator
def export(exporter, nb, **kw):
"""
Export a notebook object using specific exporter class.
Parameters
----------
exporter : class:`~IPython.nbconvert.exporters.exporter.Exporter` class or instance
Class type or instance of the exporter that should be used. If the
method initializes it's own instance of the class, it is ASSUMED that
the class type provided exposes a constructor (``__init__``) with the same
signature as the base Exporter class.
"""
#Check arguments
if exporter is None:
raise TypeError("Exporter is None")
elif not isinstance(exporter, Exporter) and not issubclass(exporter, Exporter):
raise TypeError("exporter does not inherit from Exporter (base)")
if nb is None:
raise TypeError("nb is None")
#Create the exporter
resources = kw.pop('resources', None)
if isinstance(exporter, Exporter):
exporter_instance = exporter
else:
exporter_instance = exporter(**kw)
#Try to convert the notebook using the appropriate conversion function.
if isinstance(nb, NotebookNode):
output, resources = exporter_instance.from_notebook_node(nb, resources)
elif isinstance(nb, string_types):
output, resources = exporter_instance.from_filename(nb, resources)
else:
output, resources = exporter_instance.from_file(nb, resources)
return output, resources
exporter_map = dict(
custom=TemplateExporter,
html=HTMLExporter,
slides=SlidesExporter,
latex=LatexExporter,
pdf=PDFExporter,
markdown=MarkdownExporter,
python=PythonExporter,
rst=RSTExporter,
notebook=NotebookExporter,
)
def _make_exporter(name, E):
"""make an export_foo function from a short key and Exporter class E"""
def _export(nb, **kw):
return export(E, nb, **kw)
_export.__doc__ = """Export a notebook object to {0} format""".format(name)
return _export
g = globals()
for name, E in exporter_map.items():
g['export_%s' % name] = DocDecorator(_make_exporter(name, E))
@DocDecorator
def export_by_name(format_name, nb, **kw):
"""
Export a notebook object to a template type by its name. Reflection
(Inspect) is used to find the template's corresponding explicit export
method defined in this module. That method is then called directly.
Parameters
----------
format_name : str
Name of the template style to export to.
"""
function_name = "export_" + format_name.lower()
if function_name in globals():
return globals()[function_name](nb, **kw)
else:
raise ExporterNameError("template for `%s` not found" % function_name)
def get_export_names():
"""Return a list of the currently supported export targets
WARNING: API WILL CHANGE IN FUTURE RELEASES OF NBCONVERT"""
return sorted(exporter_map.keys())