upstream/ipython Files · IPython/nbformat/v3/tests/formattest.py

Reset the interactive namespace __warningregistry__ before executing code...

Reset the interactive namespace __warningregistry__ before executing code Fixes . 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.

Bradley M. Froehle - - Load All Authors

File last commit:

r7874:4a6836ce


                r18548:61431d7d

Download file

             formattest.py
        
                    63 lines
            
             | 1.5 KiB
            
                | text/x-python
            
             |
                PythonLexer
            
             / IPython / nbformat / v3 / tests / formattest.py
          
                    History
                
                 |
                  Source
                 | Raw
                 |Copy content
                 |Copy permalink

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
      # -*- coding: utf8 -*-

      import io

      import os

      import shutil

      import tempfile

      pjoin = os.path.join

      from ..nbbase import (

          NotebookNode,

          new_code_cell, new_text_cell, new_worksheet, new_notebook

      )

      from ..nbpy import reads, writes, read, write

      from .nbexamples import nb0, nb0_py

        MinRK
    
specify utf8 when calling io.open

              r6212
            
      def open_utf8(fname, mode):

          return io.open(fname, mode=mode, encoding='utf-8')

        MinRK
    
NBFormatTest is now a mixin, rather than a base class

              r6476
            
      class NBFormatTest:

          """Mixin for writing notebook format tests"""

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
          # override with appropriate values in subclasses

          nb0_ref = None

          ext = None

          mod = None

          def setUp(self):

              self.wd = tempfile.mkdtemp()

          def tearDown(self):

              shutil.rmtree(self.wd)

          def assertNBEquals(self, nba, nbb):

        Bradley M. Froehle
    
s/assertEquals/assertEqual/

              r7874
            
              self.assertEqual(nba, nbb)

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
          def test_writes(self):

              s = self.mod.writes(nb0)

              if self.nb0_ref:

        Bradley M. Froehle
    
s/assertEquals/assertEqual/

              r7874
            
                  self.assertEqual(s, self.nb0_ref)

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
          def test_reads(self):

              s = self.mod.writes(nb0)

              nb = self.mod.reads(s)

          def test_roundtrip(self):

              s = self.mod.writes(nb0)

              self.assertNBEquals(self.mod.reads(s),nb0)

          def test_write_file(self):

        MinRK
    
specify utf8 when calling io.open

              r6212
            
              with open_utf8(pjoin(self.wd, "nb0.%s" % self.ext), 'w') as f:

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
                  self.mod.write(nb0, f)

          def test_read_file(self):

        MinRK
    
specify utf8 when calling io.open

              r6212
            
              with open_utf8(pjoin(self.wd, "nb0.%s" % self.ext), 'w') as f:

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
                  self.mod.write(nb0, f)

        MinRK
    
specify utf8 when calling io.open

              r6212
            
              with open_utf8(pjoin(self.wd, "nb0.%s" % self.ext), 'r') as f:

        MinRK
    
add NBFormatTestCase base class, to consolidate nbformat testing

              r6209
            
                  nb = self.mod.read(f)

        MinRK
    
NBFormatTest is now a mixin, rather than a base class

              r6476

	Site-wide shortcuts
/	Use quick search box
g h	Goto home page
g g	Goto my private gists page
g G	Goto my public gists page
g 0-9	Goto bookmarked items from 0-9
n r	New repository page
n g	New gist page

	Repositories
g s	Goto summary page
g c	Goto changelog page
g f	Goto files page
g F	Goto files page with file search activated
g p	Goto pull requests page
g o	Goto repository settings
g O	Goto repository access permissions settings
t s	Toggle sidebar on some pages

MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209	# -- coding: utf8 --
		import io
		import os
		import shutil
		import tempfile

		pjoin = os.path.join

		from ..nbbase import (
		NotebookNode,
		new_code_cell, new_text_cell, new_worksheet, new_notebook
		)

		from ..nbpy import reads, writes, read, write
		from .nbexamples import nb0, nb0_py


MinRK specify utf8 when calling io.open	r6212	def open_utf8(fname, mode):
		return io.open(fname, mode=mode, encoding='utf-8')

MinRK NBFormatTest is now a mixin, rather than a base class	r6476	class NBFormatTest:
		"""Mixin for writing notebook format tests"""
MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209
		# override with appropriate values in subclasses
		nb0_ref = None
		ext = None
		mod = None

		def setUp(self):
		self.wd = tempfile.mkdtemp()

		def tearDown(self):
		shutil.rmtree(self.wd)

		def assertNBEquals(self, nba, nbb):
Bradley M. Froehle s/assertEquals/assertEqual/	r7874	self.assertEqual(nba, nbb)
MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209
		def test_writes(self):
		s = self.mod.writes(nb0)
		if self.nb0_ref:
Bradley M. Froehle s/assertEquals/assertEqual/	r7874	self.assertEqual(s, self.nb0_ref)
MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209
		def test_reads(self):
		s = self.mod.writes(nb0)
		nb = self.mod.reads(s)

		def test_roundtrip(self):
		s = self.mod.writes(nb0)
		self.assertNBEquals(self.mod.reads(s),nb0)

		def test_write_file(self):
MinRK specify utf8 when calling io.open	r6212	with open_utf8(pjoin(self.wd, "nb0.%s" % self.ext), 'w') as f:
MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209	self.mod.write(nb0, f)

		def test_read_file(self):
MinRK specify utf8 when calling io.open	r6212	with open_utf8(pjoin(self.wd, "nb0.%s" % self.ext), 'w') as f:
MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209	self.mod.write(nb0, f)

MinRK specify utf8 when calling io.open	r6212	with open_utf8(pjoin(self.wd, "nb0.%s" % self.ext), 'r') as f:
MinRK add NBFormatTestCase base class, to consolidate nbformat testing	r6209	nb = self.mod.read(f)


MinRK NBFormatTest is now a mixin, rather than a base class	r6476