Mailman 3 July 2010 - Python-checkins

r83285 - python/branches/py3k/Lib/test/test_sundry.py
by georg.brandl 30 Jul '10

30 Jul '10

Author: georg.brandl Date: Fri Jul 30 17:33:52 2010 New Revision: 83285 Log: pdb now has its own tests. Modified: python/branches/py3k/Lib/test/test_sundry.py Modified: python/branches/py3k/Lib/test/test_sundry.py ============================================================================== --- python/branches/py3k/Lib/test/test_sundry.py (original) +++ python/branches/py3k/Lib/test/test_sundry.py Fri Jul 30 17:33:52 2010 @@ -54,7 +54,6 @@ import nturl2path import opcode import os2emxpath - import pdb import pstats import py_compile import rlcompleter

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r83284 - in python/branches/py3k: Doc/library/bdb.rst Lib/bdb.py
by georg.brandl 30 Jul '10

30 Jul '10

Author: georg.brandl Date: Fri Jul 30 17:01:23 2010 New Revision: 83284 Log: Add Breakpoint.bpformat(), which returns the info usually printed by bpprint(). Necessary for major refactoring of pdb output handling. Modified: python/branches/py3k/Doc/library/bdb.rst python/branches/py3k/Lib/bdb.py Modified: python/branches/py3k/Doc/library/bdb.rst ============================================================================== --- python/branches/py3k/Doc/library/bdb.rst (original) +++ python/branches/py3k/Doc/library/bdb.rst Fri Jul 30 17:01:23 2010 @@ -50,9 +50,10 @@ Mark the breakpoint as disabled. - .. method:: bpprint(out=None) + .. method:: bpformat() - Print all the information about the breakpoint: + Return a string with all the information about the breakpoint, nicely + formatted: * The breakpoint number. * If it is temporary or not. @@ -61,6 +62,13 @@ * If it must be ignored the next N times. * The breakpoint hit count. + .. versionadded:: 3.2 + + .. method:: bpprint(out=None) + + Print the output of :meth:`bpformat` to the file *out*, or if it is + ``None``, to standard output. + .. class:: Bdb(skip=None) Modified: python/branches/py3k/Lib/bdb.py ============================================================================== --- python/branches/py3k/Lib/bdb.py (original) +++ python/branches/py3k/Lib/bdb.py Fri Jul 30 17:01:23 2010 @@ -499,6 +499,9 @@ def bpprint(self, out=None): if out is None: out = sys.stdout + print(self.bpformat(), file=out) + + def bpformat(self): if self.temporary: disp = 'del ' else: @@ -507,17 +510,19 @@ disp = disp + 'yes ' else: disp = disp + 'no ' - print('%-4dbreakpoint %s at %s:%d' % (self.number, disp, - self.file, self.line), file=out) + ret = '%-4dbreakpoint %s at %s:%d' % (self.number, disp, + self.file, self.line) if self.cond: - print('\tstop only if %s' % (self.cond,), file=out) + ret += '\n\tstop only if %s' % (self.cond,) if self.ignore: - print('\tignore next %d hits' % (self.ignore), file=out) - if (self.hits): - if (self.hits > 1): ss = 's' - else: ss = '' - print(('\tbreakpoint already hit %d time%s' % - (self.hits, ss)), file=out) + ret += '\n\tignore next %d hits' % (self.ignore,) + if self.hits: + if self.hits > 1: + ss = 's' + else: + ss = '' + ret += '\n\tbreakpoint already hit %d time%s' % (self.hits, ss) + return ret def __str__(self): return 'breakpoint %s at %s:%s' % (self.number, self.file, self.line)

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r83283 - python/branches/py3k/Lib/test/test_pdb.py
by georg.brandl 30 Jul '10

30 Jul '10

Author: georg.brandl Date: Fri Jul 30 16:16:43 2010 New Revision: 83283 Log: #7964 followup: add test case to ensure issue remains fixed. Modified: python/branches/py3k/Lib/test/test_pdb.py Modified: python/branches/py3k/Lib/test/test_pdb.py ============================================================================== --- python/branches/py3k/Lib/test/test_pdb.py (original) +++ python/branches/py3k/Lib/test/test_pdb.py Fri Jul 30 16:16:43 2010 @@ -1,7 +1,10 @@ # A test suite for pdb; not very comprehensive at the moment. import imp +import pdb import sys +import unittest +import subprocess from test import support # This little helper class is essential for testing pdb under doctest. @@ -286,9 +289,30 @@ """ +class PdbTestCase(unittest.TestCase): + + def test_issue7964(self): + # open the file as binary so we can force \r\n newline + with open(support.TESTFN, 'wb') as f: + f.write(b'print("testing my pdb")\r\n') + cmd = [sys.executable, '-m', 'pdb', support.TESTFN] + proc = subprocess.Popen(cmd, + stdout=subprocess.PIPE, + stdin=subprocess.PIPE, + stderr=subprocess.STDOUT, + ) + stdout, stderr = proc.communicate(b'quit\n') + self.assertNotIn(b'SyntaxError', stdout, + "Got a syntax error running test script under PDB") + + def tearDown(self): + support.unlink(support.TESTFN) + + def test_main(): from test import test_pdb support.run_doctest(test_pdb, verbosity=True) + support.run_unittest(PdbTestCase) if __name__ == '__main__':

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r83282 - in python/branches/release27-maint/Lib: pdb.py test/test_pdb.py
by georg.brandl 30 Jul '10

30 Jul '10

Author: georg.brandl Date: Fri Jul 30 16:14:42 2010 New Revision: 83282 Log: Revert r83267, as it breaks a few doctests and generally leads to ugly truncated output. Modified: python/branches/release27-maint/Lib/pdb.py python/branches/release27-maint/Lib/test/test_pdb.py Modified: python/branches/release27-maint/Lib/pdb.py ============================================================================== --- python/branches/release27-maint/Lib/pdb.py (original) +++ python/branches/release27-maint/Lib/pdb.py Fri Jul 30 16:14:42 2010 @@ -237,7 +237,7 @@ if type(t) == type(''): exc_type_name = t else: exc_type_name = t.__name__ - print >>self.stdout, '***', exc_type_name + ':', _saferepr(v) + print >>self.stdout, '***', exc_type_name + ':', v def precmd(self, line): """Handle alias expansion and ';;' separator.""" @@ -753,7 +753,7 @@ if isinstance(t, str): exc_type_name = t else: exc_type_name = t.__name__ - print >>self.stdout, '***', exc_type_name + ':', _saferepr(v) + print >>self.stdout, '***', exc_type_name + ':', repr(v) raise def do_p(self, arg): Modified: python/branches/release27-maint/Lib/test/test_pdb.py ============================================================================== --- python/branches/release27-maint/Lib/test/test_pdb.py (original) +++ python/branches/release27-maint/Lib/test/test_pdb.py Fri Jul 30 16:14:42 2010 @@ -126,33 +126,6 @@ """ -def test_pdb_unicode_exception(): - r"""This tests exceptions that cannot be displayed due to Unicode issues. - http://bugs.python.org/issue7539 - - >>> def test_function(): - ... import pdb; pdb.Pdb().set_trace() - ... pass - - >>> def raising_function(): - ... raise ValueError(u"\xff") - - >>> with PdbTestInput([ - ... 'raising_function()', - ... 'p raising_function()', - ... 'continue', - ... ]): - ... test_function() - > <doctest test.test_pdb.test_pdb_unicode_exception[0]>(3)test_function() - -> pass - (Pdb) raising_function() - *** ValueError: ValueError(u'\xff',) - (Pdb) p raising_function() - *** ValueError: ValueError(u'\xff',) - (Pdb) continue - """ - - def test_main(): from test import test_pdb test_support.run_doctest(test_pdb, verbosity=True)

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r83281 - python/branches/py3k/Misc/maintainers.rst
by georg.brandl 30 Jul '10

30 Jul '10

Author: georg.brandl Date: Fri Jul 30 15:36:43 2010 New Revision: 83281 Log: Add myself for pdb. Modified: python/branches/py3k/Misc/maintainers.rst Modified: python/branches/py3k/Misc/maintainers.rst ============================================================================== --- python/branches/py3k/Misc/maintainers.rst (original) +++ python/branches/py3k/Misc/maintainers.rst Fri Jul 30 15:36:43 2010 @@ -147,7 +147,7 @@ os ossaudiodev parser -pdb +pdb georg.brandl pickle alexandre.vassalotti, pitrou pickletools alexandre.vassalotti pipes

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r83280 - tracker/instances/python-dev/detectors/sendmail.py
by ezio.melotti 30 Jul '10

30 Jul '10

Author: ezio.melotti Date: Fri Jul 30 15:28:06 2010 New Revision: 83280 Log: #279: Removing a message sends an empty changenote to nosy users. Modified: tracker/instances/python-dev/detectors/sendmail.py Modified: tracker/instances/python-dev/detectors/sendmail.py ============================================================================== --- tracker/instances/python-dev/detectors/sendmail.py (original) +++ tracker/instances/python-dev/detectors/sendmail.py Fri Jul 30 15:28:06 2010 @@ -61,7 +61,7 @@ pass # New submission? - if None == oldvalues: + if oldvalues == None: changenote = cl.generateCreateNote(nodeid) try: # Add triage addresses @@ -71,7 +71,8 @@ oldfiles = [] else: changenote = cl.generateChangeNote(nodeid, oldvalues) - oldfiles = oldvalues.get('files', []) + oldfiles = oldvalues.get('files', []) + oldmsglist = oldvalues.get('messages', []) # Silence nosy_count/message_count lines = changenote.splitlines() @@ -89,9 +90,14 @@ changenote+="\nAdded file: %s" % url for fid in removed: url = db.config.TRACKER_WEB + "file%s/%s" % \ - (fid, db.file.get(fid, "name")) + (fid, db.file.get(fid, "name")) changenote+="\nRemoved file: %s" % url + # detect if any of the messages has been removed + newmsglist = db.issue.get(nodeid, 'messages', []) + for msgid in set(oldmsglist)-set(newmsglist): + url = db.config.TRACKER_WEB + "msg%s" % msgid + changenote += "\nRemoved message: %s" % url authid = db.getuid()

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r83279 - in python/branches/release27-maint: Doc/library/functions.rst
by mark.dickinson 30 Jul '10

30 Jul '10

Author: mark.dickinson Date: Fri Jul 30 15:16:07 2010 New Revision: 83279 Log: Merged revisions 83277 via svnmerge from svn+ssh://pythondev@svn.python.org/python/branches/py3k ........ r83277 | mark.dickinson | 2010-07-30 14:13:02 +0100 (Fri, 30 Jul 2010) | 1 line Add note about surprising behaviour from round function. ........ Modified: python/branches/release27-maint/ (props changed) python/branches/release27-maint/Doc/library/functions.rst Modified: python/branches/release27-maint/Doc/library/functions.rst ============================================================================== --- python/branches/release27-maint/Doc/library/functions.rst (original) +++ python/branches/release27-maint/Doc/library/functions.rst Fri Jul 30 15:16:07 2010 @@ -1095,6 +1095,14 @@ example, ``round(0.5)`` is ``1.0`` and ``round(-0.5)`` is ``-1.0``). + .. note:: + + The behavior of :func:`round` for floats can be surprising: for example, + ``round(2.675, 2)`` gives ``2.67`` instead of the expected ``2.68``. + This is not a bug: it's a result of the fact that most decimal fractions + can't be represented exactly as a float. See :ref:`tut-fp-issues` for + more information. + .. function:: set([iterable]) :noindex:

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r83278 - in python/branches/release31-maint: Doc/library/functions.rst
by mark.dickinson 30 Jul '10

30 Jul '10

Author: mark.dickinson Date: Fri Jul 30 15:13:54 2010 New Revision: 83278 Log: Merged revisions 83277 via svnmerge from svn+ssh://pythondev@svn.python.org/python/branches/py3k ........ r83277 | mark.dickinson | 2010-07-30 14:13:02 +0100 (Fri, 30 Jul 2010) | 1 line Add note about surprising behaviour from round function. ........ Modified: python/branches/release31-maint/ (props changed) python/branches/release31-maint/Doc/library/functions.rst Modified: python/branches/release31-maint/Doc/library/functions.rst ============================================================================== --- python/branches/release31-maint/Doc/library/functions.rst (original) +++ python/branches/release31-maint/Doc/library/functions.rst Fri Jul 30 15:13:54 2010 @@ -961,6 +961,13 @@ The return value is an integer if called with one argument, otherwise of the same type as *x*. + .. note:: + + The behavior of :func:`round` for floats can be surprising: for example, + ``round(2.675, 2)`` gives ``2.67`` instead of the expected ``2.68``. + This is not a bug: it's a result of the fact that most decimal fractions + can't be represented exactly as a float. See :ref:`tut-fp-issues` for + more information. .. function:: set([iterable]) :noindex:

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r83277 - python/branches/py3k/Doc/library/functions.rst
by mark.dickinson 30 Jul '10

30 Jul '10

Author: mark.dickinson Date: Fri Jul 30 15:13:02 2010 New Revision: 83277 Log: Add note about surprising behaviour from round function. Modified: python/branches/py3k/Doc/library/functions.rst Modified: python/branches/py3k/Doc/library/functions.rst ============================================================================== --- python/branches/py3k/Doc/library/functions.rst (original) +++ python/branches/py3k/Doc/library/functions.rst Fri Jul 30 15:13:02 2010 @@ -972,6 +972,13 @@ The return value is an integer if called with one argument, otherwise of the same type as *x*. + .. note:: + + The behavior of :func:`round` for floats can be surprising: for example, + ``round(2.675, 2)`` gives ``2.67`` instead of the expected ``2.68``. + This is not a bug: it's a result of the fact that most decimal fractions + can't be represented exactly as a float. See :ref:`tut-fp-issues` for + more information. .. function:: set([iterable]) :noindex:

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r83276 - python/branches/release27-maint/Doc/tutorial/floatingpoint.rst
by mark.dickinson 30 Jul '10

30 Jul '10

Author: mark.dickinson Date: Fri Jul 30 14:58:44 2010 New Revision: 83276 Log: Update the floating-point section of the tutorial for the short float repr. Modified: python/branches/release27-maint/Doc/tutorial/floatingpoint.rst Modified: python/branches/release27-maint/Doc/tutorial/floatingpoint.rst ============================================================================== --- python/branches/release27-maint/Doc/tutorial/floatingpoint.rst (original) +++ python/branches/release27-maint/Doc/tutorial/floatingpoint.rst Fri Jul 30 14:58:44 2010 @@ -48,32 +48,37 @@ 0.0001100110011001100110011001100110011001100110011... -Stop at any finite number of bits, and you get an approximation. This is why -you see things like:: +Stop at any finite number of bits, and you get an approximation. On a typical +machine, there are 53 bits of precision available, so the value stored +internally is the binary fraction :: + + 0.00011001100110011001100110011001100110011001100110011010 + +which is close to, but not exactly equal to, 1/10. + +It's easy to forget that the stored value is an approximation to the original +decimal fraction, because of the way that floats are displayed at the +interpreter prompt. Python only prints a decimal approximation to the true +decimal value of the binary approximation stored by the machine. If Python +were to print the true decimal value of the binary approximation stored for +0.1, it would have to display :: >>> 0.1 - 0.10000000000000001 + 0.1000000000000000055511151231257827021181583404541015625 -On most machines today, that is what you'll see if you enter 0.1 at a Python -prompt. You may not, though, because the number of bits used by the hardware to -store floating-point values can vary across machines, and Python only prints a -decimal approximation to the true decimal value of the binary approximation -stored by the machine. On most machines, if Python were to print the true -decimal value of the binary approximation stored for 0.1, it would have to -display :: +That is more digits than most people find useful, so Python keeps the number +of digits manageable by displaying a rounded value instead :: >>> 0.1 - 0.1000000000000000055511151231257827021181583404541015625 + 0.1 -instead! The Python prompt uses the built-in :func:`repr` function to obtain a -string version of everything it displays. For floats, ``repr(float)`` rounds -the true decimal value to 17 significant digits, giving :: - - 0.10000000000000001 - -``repr(float)`` produces 17 significant digits because it turns out that's -enough (on most machines) so that ``eval(repr(x)) == x`` exactly for all finite -floats *x*, but rounding to 16 digits is not enough to make that true. +It's important to realize that this is, in a real sense, an illusion: the value +in the machine is not exactly 1/10, you're simply rounding the *display* of the +true machine value. This fact becomes apparent as soon as you try to do +arithmetic with these values :: + + >>> 0.1 + 0.2 + 0.30000000000000004 Note that this is in the very nature of binary floating-point: this is not a bug in Python, and it is not a bug in your code either. You'll see the same kind of @@ -81,31 +86,32 @@ (although some languages may not *display* the difference by default, or in all output modes). -Python's built-in :func:`str` function produces only 12 significant digits, and -you may wish to use that instead. It's unusual for ``eval(str(x))`` to -reproduce *x*, but the output may be more pleasant to look at:: - - >>> print str(0.1) - 0.1 - -It's important to realize that this is, in a real sense, an illusion: the value -in the machine is not exactly 1/10, you're simply rounding the *display* of the -true machine value. - -Other surprises follow from this one. For example, after seeing :: - - >>> 0.1 - 0.10000000000000001 +Other surprises follow from this one. For example, if you try to round the value +2.675 to two decimal places, you get this :: -you may be tempted to use the :func:`round` function to chop it back to the -single digit you expect. But that makes no difference:: + >>> round(2.675, 2) + 2.67 - >>> round(0.1, 1) - 0.10000000000000001 - -The problem is that the binary floating-point value stored for "0.1" was already -the best possible binary approximation to 1/10, so trying to round it again -can't make it better: it was already as good as it gets. +The documentation for the built-in :func:`round` function says that it rounds +to the nearest value, rounding ties away from zero. Since the decimal fraction +2.675 is exactly halfway between 2.67 and 2.68, you might expect the result +here to be (a binary approximation to) 2.68. It's not, because when the +decimal literal ``2.675`` is converted to a binary floating-point number, it's +again replaced with a binary approximation, whose exact value is :: + + 2.67499999999999982236431605997495353221893310546875 + +Since this approximation is slightly closer to 2.67 than to 2.68, it's rounded +down. + +If you're in a situation where you care which way your decimal halfway-cases +are rounded, you should consider using the :mod:`decimal` module. +Incidentally, the :mod:`decimal` module also provides a nice way to "see" the +exact value that's stored in any particular Python float :: + + >>> from decimal import Decimal + >>> Decimal(2.675) + Decimal('2.67499999999999982236431605997495353221893310546875') Another consequence is that since 0.1 is not exactly 1/10, summing ten values of 0.1 may not yield exactly 1.0, either:: @@ -150,15 +156,15 @@ This is the chief reason why Python (or Perl, C, C++, Java, Fortran, and many others) often won't display the exact decimal number you expect:: - >>> 0.1 - 0.10000000000000001 + >>> 0.1 + 0.2 + 0.30000000000000004 -Why is that? 1/10 is not exactly representable as a binary fraction. Almost all -machines today (November 2000) use IEEE-754 floating point arithmetic, and -almost all platforms map Python floats to IEEE-754 "double precision". 754 -doubles contain 53 bits of precision, so on input the computer strives to -convert 0.1 to the closest fraction it can of the form *J*/2**\ *N* where *J* is -an integer containing exactly 53 bits. Rewriting :: +Why is that? 1/10 and 2/10 are not exactly representable as a binary +fraction. Almost all machines today (July 2010) use IEEE-754 floating point +arithmetic, and almost all platforms map Python floats to IEEE-754 "double +precision". 754 doubles contain 53 bits of precision, so on input the computer +strives to convert 0.1 to the closest fraction it can of the form *J*/2**\ *N* +where *J* is an integer containing exactly 53 bits. Rewriting :: 1 / 10 ~= J / (2**N) @@ -211,9 +217,8 @@ 100000000000000005551115123125L meaning that the exact number stored in the computer is approximately equal to -the decimal value 0.100000000000000005551115123125. Rounding that to 17 -significant digits gives the 0.10000000000000001 that Python displays (well, -will display on any 754-conforming platform that does best-possible input and -output conversions in its C library --- yours may not!). - - +the decimal value 0.100000000000000005551115123125. In versions prior to +Python 2.7 and Python 3.1, Python rounded this value to 17 significant digits, +giving '0.10000000000000001'. In current versions, Python displays a value based +on the shortest decimal fraction that rounds correctly back to the true binary +value, resulting simply in '0.1'.

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