date:20150823

On Sunday 23 Aug 2015 16:05 CEST, Johannes Bauer wrote:

 On 22.08.2015 16:15, Christian Gollwitzer wrote:

 Probably yes. You should take a look at the OP again and compare
 the time stamps. It says that in between two consecutive calls of
 the same program, the request was served once in a second, and once
 with serious delays. Despite that the server is localhost. In
 between both trials there are 20 seconds. I do not see, how git
 bisect would help here.

 I do completely understand that in two consecutive runs one time the
 problem occurs and the other time it doesn't.

 It's highly unlikely that such a bug would ever have passed the
 bottle QA and if it did it would affect thousands of users (who
 would report this issue, since it's very severe). It is much more
 likely the bug is somewhere within the OP's program. By git bisect
 he can find out where he introduced the bug.

You have to explain something to me: how can I introduce a bug without
changing anything? Maybe by having wrong thoughts?


 Note that this says nothing about the location of the bug, in can
 still be either in the OPs code or in the framework.

 Yup. Note that he has now shifted from blaming bottle to blaming
 Firefox. Same thing with that claim. If somehow website delivery was
 delayed 6 seconds reproducibly, people would have noticed.

I never blamed bottle, I was asking if it could be a problem with
bottle.

And it is (now) clear that it has to do something with Firefox. Just
fetching the URL's does not give a problem. Chromium does not have a
problem. Only Firefox has a problem. Even in safemode. And with an
older version of Firefox there is (almost) no problem.


 I suspect that either the OPs program is at fault or the OP's setup
 (name resolution or some other weird stuff going on). But instead of
 tackling this problem systematically, like a Software Engineer would
 (Wireshark, debugger, profiler) he just blames other people's
 software. This, in my humble opinion, is annoying as fuck.

Do you know what I find annoying? That you need to keep bashing me,
instead of thinking: was I maybe wrong in bashing? Especially because
you are the only one that thinks you were right. Being the only one
who thinks something, does not necessarily make you wrong, but should
make you contemplate.

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[issue16379] SQLite error code not exposed to python

2015-08-23 Thread Gerhard Häring


Gerhard Häring added the comment:

I propose to also set the SQLite extended error code if this is implemented.

What's the reasoning behind offering a error code to name mapping? This seem 
problematic to me. In case a newer SQLite version introduces a new error code, 
this error code cannot be found in the mapping. I propose to leave this out in 
order to not have this problem.

Otherwise we will have people depending on any error code being able to be 
found in this mapping.

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Re: Sometimes bottle takes a lot of time

On Sunday 23 Aug 2015 17:44 CEST, MRAB wrote:

 I never blamed bottle, I was asking if it could be a problem with
 bottle.

 The subject says otherwise. :-)

Yeah, my communication skills can take some improvement. I meant: I
have this problem. I think it could have to do something with bottle.
Can anybody shed some light on it?

I hope to be more precise next time.

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Alecsandru Patrascu added the comment:

I received the review and will post new patch versions as soon as I update 
them. 

Regarding PGO on clang, I will need a bit more time to edit the Makefile and 
will post it just for clang, to be easier for us to see the differences.

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Re: Sometimes bottle takes a lot of time

2015-08-23 Thread MRAB


On 2015-08-23 16:20, Cecil Westerhof wrote:

On Sunday 23 Aug 2015 16:05 CEST, Johannes Bauer wrote:


On 22.08.2015 16:15, Christian Gollwitzer wrote:


Probably yes. You should take a look at the OP again and compare
the time stamps. It says that in between two consecutive calls of
the same program, the request was served once in a second, and once
with serious delays. Despite that the server is localhost. In
between both trials there are 20 seconds. I do not see, how git
bisect would help here.


I do completely understand that in two consecutive runs one time the
problem occurs and the other time it doesn't.

It's highly unlikely that such a bug would ever have passed the
bottle QA and if it did it would affect thousands of users (who
would report this issue, since it's very severe). It is much more
likely the bug is somewhere within the OP's program. By git bisect
he can find out where he introduced the bug.


You have to explain something to me: how can I introduce a bug without
changing anything? Maybe by having wrong thoughts?



Note that this says nothing about the location of the bug, in can
still be either in the OPs code or in the framework.


Yup. Note that he has now shifted from blaming bottle to blaming
Firefox. Same thing with that claim. If somehow website delivery was
delayed 6 seconds reproducibly, people would have noticed.


I never blamed bottle, I was asking if it could be a problem with
bottle.


The subject says otherwise. :-)

[snip]

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Re: Qestion

2015-08-23 Thread Laura Creighton

In a message of Sat, 22 Aug 2015 06:53:21 -, ali ranjbar writes:
hi dear friend

I have python version 2.4.3

Which version of PIL is appropriate for me and how can I add it to my systems?

Regards

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If you really have python 2.4.3 then you badly need a newer Python.
However Pillow, with a version number 2.0 is promised to work for
you.  https://pillow.readthedocs.org/installation.html
The latest 1.x version of Pillow is https://pypi.python.org/pypi/Pillow/1.7.8
so you can get this.

Or did you mean that you have python 3.4.3 ?
In which case you still want Pillow
but this one.  https://pypi.python.org/pypi/Pillow/2.9.0
And this one may already come as a package for your system, if you
don't want to use pip.

Laura
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[issue22140] python-config --includes returns a wrong path (double prefix)

2015-08-23 Thread Alexey Gorshkov


Alexey Gorshkov added the comment:

I don't understand: Why python-config needs to seek realpath? Why 
python-config is trying to be smarter than one who starts ./configure script?

As so, the right thing to this, is remove smart parts from python-config. But 
as for fast hack in to this is replace line 'prefix_real=$(installed_prefix 
$0)' with 'prefix_real=$prefix_build'.

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Re: Sometimes bottle takes a lot of time

On Sunday 23 Aug 2015 03:05 CEST, Chris Angelico wrote:

 But in principal I have found the problem. (Not the reason.) The
 problem is Firefox. (So it is not bottle and also not AngularJS.)
 When using Chrome there is no problem. Not even when I do 15 times
 a refresh. With Firefox there is this problem. Even when I restart
 it.

 Huh, interesting. I can't help there, but I wish you the very best
 of luck in finding it.

It looks like it is a recent problem. I also installed it on an old
AcerAspire One. The fetch takes there five times as long, but fetching
through Firefox is a lot faster. Not as fast as Chromium, but the
difference is a lot less. But there Ice-wasel 38.0 is used instead of
Firefox 40.

Mozilla wants a life version. I am trying to install it on
PythonAnywhere.

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Good resource for pythonanywhere and WSGI

I want to host my web application on pythonanywhere so that the people
of Mozilla can investigate the problem it has with this application. I
do not find documentation that is useful for me. Has anyone a good
resource?

The application I want to deploy on pythonanywhere:
https://github.com/CecilWesterhof/PublishedPhotos

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Changes by Alecsandru Patrascu alecsandru.patra...@intel.com:


Removed file: http://bugs.python.org/file40226/python2.7-3.6-pgo.zip

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Changes by Alecsandru Patrascu alecsandru.patra...@intel.com:


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Added file: http://bugs.python.org/file40231/python2.7-pgo.patch

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Added file: http://bugs.python.org/file40232/python3.6-pgo.patch

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[issue24914] Python: Not just OO style but this is not mentioned on python.org or in FAQ

2015-08-23 Thread Paddy McCarthy


Paddy McCarthy added the comment:

OK, here's a suggested re-wording:

Python is an interpreted, interactive, object-oriented programming language 
that also supports programming in procedural and functional styles. It 
incorporates modules, exceptions, dynamic typing, very high level dynamic data 
types, and classes; but statements are not required to be contained in class 
definitions and functions are first class - being able to be composed, returned 
from other functions and be a member of other container types such as dicts, 
sets, and lists.

If that is too long,an alternative would be to delete my addition to the last 
sentence from ; but classes are not ... Leaving it to the reader to research 
just how procedural and functional Python can be. (Where should a programmer, 
but newbie-to-Python look)?

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Re: Is this the way to go with SQLite

2015-08-23 Thread Chris Angelico

On Sun, Aug 23, 2015 at 11:18 PM, Cecil Westerhof ce...@decebal.nl wrote:
 Also an URL is unique, so I need to check that if it is found, the
 values are the same as the ones I wanted to insert.

And if they aren't? Currently, all you do is print out a message and
continue on; what happens if you get the same URL coming up more than
once?

 select_url  = '''SELECT year
  ,  month
  ,  description
  FROM   LINKS
  WHERE  URL = ?'''
 year= 2015
 month   = 8

PEP 8 has a word or two to say about this, but carry on. Incidentally,
I'd be inclined to put the SELECT query down below, same as the INSERT
query is; it's not in any way different from just using a string
literal there, and this separates two pieces of code (IMO)
unnecessarily.

 for link in links:
 description = link[0]
 url = link[1]

for description, url in links:

 url_values  = c.execute(select_url, [url]).fetchall()
 if len(url_values) == 0:

if not url_values:

 print('Adding {0}'.format(link))
 c.execute('''INSERT INTO links
  (year, month, description, URL)
  VALUES
  (?, ?, ?, ?)
   ''',
   [year, month, description, url])
 else:
 to_insert   = (year, month, description)
 found   = url_values[0]
 if found != to_insert:
 print('For {0} found {1} instead of {2}'.format(url, found, 
 to_insert))

Otherwise, looks reasonable. I'm normally expecting to see this kind
of query, and if it isn't there, insert code to have an UPDATE in
its other branch (which makes it into a classic upsert or merge
operation - what MySQL calls INSERT... ON DUPLICATE KEY UPDATE), or
else throw an error (in which case the cleanest way is to put a unique
key on the column in question and let the database throw the error).
The risk normally is of a race condition; you could execute your
SELECT query, find no results, and then have someone else insert one
just a moment before you do. But with SQLite, you're probably assuming
no other writers anyway - an assumption which (I think) you can
mandate simply by opening a transaction and holding it through the
full update procedure - which would make this safe.

ChrisA
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Alecsandru Patrascu added the comment:

The patches are tested on Linux machines, with GNU GCC 4.8.3. From your output 
I see that you are using the CLANG compiler. CLANG uses a different set of 
flags for PGO that are not compatible with GCC's, therefore the compilation 
will fail. Can you please use the GNU GCC compiler to test the patches?

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Re: how to handle cpu cache in python ( or fastest way to call a function once)

2015-08-23 Thread Steven D'Aprano

On Sun, 23 Aug 2015 04:10 pm, Yuzhi Xu wrote:

 I find out that python's VM seems to be very unfriendly with CPU-Cache.

Possibly. More comments below.


 for example:
 ***
 import time
 a = range(500)
 
 sum(a)
 
 for i in range(100): #just to create a time interval, seems this
 disturb cpu cache?
 pass
 
 
 st = time.time()
 sum(a)
 print (time.time() - st)*1e6
 
 *
 time: 100us

On my machine, I get about 20-25 μs for this:

(a.py contains your code above)

[steve@ando ~]$ python2.7 a.py
21.9345092773
[steve@ando ~]$ python2.7 a.py
21.9345092773
[steve@ando ~]$ python2.7 a.py
24.0802764893
[steve@ando ~]$ python2.7 a.py
23.8418579102



 another case:
 *
 import time
 a = range(500)
 
 for i in range(10):
 st = time.time()
 sum(a)
 print (time.time() - st)*1e6
 
 *
 time:~ 20us


Running this as b.py, I get times of around 15μs, a bit faster than the
first version, but not a factor of five times faster as you get.

[steve@ando ~]$ python2.7 b.py
[...]
15.0203704834
15.0203704834
25.0339508057
16.9277191162
20.0271606445
94.8905944824
15.9740447998
15.0203704834
15.0203704834
15.0203704834
15.0203704834
14.066696167
13.8282775879
15.0203704834
Traceback (most recent call last):
  File b.py, line 6, in module
sum(a)
KeyboardInterrupt


Above, you say:

 for i in range(100): #just to create a time interval, seems this
 disturb cpu cache?
 pass

But remember that range() is a function, and so, yes, it may disturb the CPU
cache. What did you expect?

But I'm not sure how the CPU cache will interact with code in a high-level
language like Python. I suspect that more likely, it simply has something
to do with range(100) building an enormous list of integers.

Here's another version:

[steve@ando ~]$ cat c.py
import time
a = range(500)
sum(a)
for i in range(100):
pass
sum(a)
st = time.time()
sum(a)
print (time.time() - st)*1e6

[steve@ando ~]$ python2.7 c.py
15.9740447998



And one more:


[steve@ando ~]$ cat d.py
import time
a = range(500)
sum(a)
for i in xrange(100): # Use xrange instead of range
pass
st = time.time()
sum(a)
print (time.time() - st)*1e6

[steve@ando ~]$ python2.7 d.py
22.1729278564
[steve@ando ~]$ python2.7 d.py
23.1266021729



So... on my machine, the difference between xrange and range makes no
difference: in both cases, calling sum() takes about 22μs.

But calling sum() twice speeds up the second call to about 16μs, or about
25% faster. (Not 80% faster, as you find.)


One last test:


[steve@ando ~]$ cat e.py
import time
a = range(500)
# Without warm-up.
st = time.time()
sum(a)
print (time.time() - st)*1e6
# Second time, with warm-up.
st = time.time()
sum(a)
print (time.time() - st)*1e6
# Add a delay.
for i in xrange(1000):
pass
st = time.time()
sum(a)
print (time.time() - st)*1e6
st = time.time()
sum(a)
print (time.time() - st)*1e6


[steve@ando ~]$ python2.7 e.py
15.0203704834
15.0203704834
10.9672546387
10.9672546387
[steve@ando ~]$ python2.7 e.py
15.9740447998
12.8746032715
12.1593475342
10.9672546387
[steve@ando ~]$ python2.7 e.py
15.9740447998
20.0271606445
15.0203704834
15.9740447998




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Alecsandru Patrascu added the comment:

I added the patches as individual files and removed the zip file.

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Re: Sometimes bottle takes a lot of time

2015-08-23 Thread Johannes Bauer

On 22.08.2015 16:15, Christian Gollwitzer wrote:

 Probably yes. You should take a look at the OP again and compare the
 time stamps. It says that in between two consecutive calls of the same
 program, the request was served once in a second, and once with serious
 delays. Despite that the server is localhost. In between both trials
 there are 20 seconds. I do not see, how git bisect would help here.

I do completely understand that in two consecutive runs one time the
problem occurs and the other time it doesn't.

It's highly unlikely that such a bug would ever have passed the bottle
QA and if it did it would affect thousands of users (who would report
this issue, since it's very severe). It is much more likely the bug is
somewhere within the OP's program. By git bisect he can find out where
he introduced the bug.

 Note that this says nothing about the location of the bug, in can still
 be either in the OPs code or in the framework.

Yup. Note that he has now shifted from blaming bottle to blaming
Firefox. Same thing with that claim. If somehow website delivery was
delayed 6 seconds reproducibly, people would have noticed.

I suspect that either the OPs program is at fault or the OP's setup
(name resolution or some other weird stuff going on). But instead of
tackling this problem systematically, like a Software Engineer would
(Wireshark, debugger, profiler) he just blames other people's software.
This, in my humble opinion, is annoying as fuck.

Cheers,
Johannes

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Re: Sandboxing Python

2015-08-23 Thread Akira Li

Mark Lawrence breamore...@yahoo.co.uk writes:

 I was always led to believe that the subject was a difficult thing to
 do, but here
 https://www.reddit.com/r/learnpython/comments/3huz4x/how_to_do_math_inside_raw_input/
 is a safe solution in only 23 characters, or are there any discernable
 flaws in it?

Related: 
http://stackoverflow.com/questions/2371436/evaluating-a-mathematical-expression-in-a-string

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[issue8987] Distutils doesn't quote Windows command lines properly

2015-08-23 Thread Jason R. Coombs


Jason R. Coombs added the comment:

I'm not upset by the idea of monkey patching in Setuptools for vetting certain 
techniques. I've even considered having Setuptools adopt distutils entirely. 
Today I filed https://bitbucket.org/pypa/setuptools/issues/417/adopt-distutils 
to seed the discussion on that possibility. For the sake of this discussion, I 
would happily accept a pull request to supply the forward-compatible version of 
_nt_quote_args (or similar), allowing a window for other libraries to make the 
switch against versions of Python supported by Setuptools.

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Re: how to handle cpu cache in python ( or fastest way to call a function once)

2015-08-23 Thread Vladimir Ignatov

Hi,

 for i in range(100): #just to create a time interval, seems this disturb 
 cpu cache?
 pass

Python interpreter consumes memory quite extensively because
everything is object.  So constructions like:

range(100):

_take_ memory.  Additionally it will trigger garbage collecting code
on deallocation time so expect even more delay.
To get most out of Python - all numbers crushing / pixel pushing /
store gigabytes code should go to low-level compiled binary
libraries.


Vladimir

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[issue24915] Profile Guided Optimization active by-default

2015-08-23 Thread Skip Montanaro


Skip Montanaro added the comment:

Is this supposed to work on Macs using Apple's version of gcc? I've got the 
latest version of Yosemite and XCode, and am getting these warnings when trying 
to build 2.7:

clang: warning: argument unused during compilation: '-fprofile-generate'

Should this be enabled using a configure check? Perhaps gcc/clang supports this 
but spells the feature differently. gcc --help tells me:

% gcc --help | egrep profile
  -fprofile-instr-generate
  -fprofile-instr-use=value
  Use instrumentation data for profile-guided 
optimization
  -fprofile-sample-use=value
  Enable sample-based profile guided optimizations

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[issue24915] Profile Guided Optimization active by-default

2015-08-23 Thread Skip Montanaro


Skip Montanaro added the comment:

It is executed using the gcc command:

% gcc -c -fno-strict-aliasing -g -O2 -DNDEBUG -g -fwrapv -O3 -Wall 
-Wstrict-prototypes  -fprofile-generate -I. -IInclude -I./Include   
-DPy_BUILD_CORE -o Modules/gcmodule.o Modules/gcmodule.c
clang: warning: argument unused during compilation: '-fprofile-generate'
% type gcc
gcc is /usr/bin/gcc

I have no idea if you can even use something other than clang on Macs now. In 
any case, the default compiler should work to build Python out of the box, if 
necessary, by checking things during configure.

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[issue8987] Distutils doesn't quote Windows command lines properly

2015-08-23 Thread Steve Dower


Steve Dower added the comment:

I notice you say adopt rather than vendor - effectively removing distutils 
from the stdlib?

It could work, but to really be able to move distutils forward we need some 
sort of side-by-side versioning, such that a package can declare which version 
of distutils is required, preferably without needing to download old versions 
on the fly when building. I'm sure it's possible but haven't got a complete 
vision yet.

Maybe it's as simple as having flags that setup scripts enable before they 
build?

import distutils
distutils.enable(distutils.flags.smart_quote_args)

That way we can actually change things without breaking old build scripts. 
Should be just as feasible if setuptools adopts distutils, but there'll 
probably be opposition from elsewhere along the lines of including core 
functionality in the stdlib.

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how to handle cpu cache in python ( or fastest way to call a function once)

2015-08-23 Thread Yuzhi Xu

I find out that python's VM seems to be very unfriendly with CPU-Cache.


see:
http://stackoverflow.com/questions/32163585/how-to-handle-cpu-cache-in-python-or-fastest-way-to-call-a-function-once

http://stackoverflow.com/questions/32153178/python-functionor-a-code-block-runs-much-slower-with-a-time-interval-in-a-loop




for example:
***
import time
a = range(500)

sum(a)

for i in range(100): #just to create a time interval, seems this disturb 
cpu cache?
pass


st = time.time()
sum(a)
print (time.time() - st)*1e6

*
time: 100us


another case:
*
import time
a = range(500)

for i in range(10):
st = time.time()
sum(a)
print (time.time() - st)*1e6

*
time:~ 20us


we can see when running frequently, the code becomes much faster.

is there a solution?


I feel this question is very difficult. one must has indepth unstanding about 
the mechanism of python virtual machine, c and cpu-cache.

Do you have any suggestion about where to post this question for a possible 
answer?
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Re: how to handle cpu cache in python ( or fastest way to call a function once)

2015-08-23 Thread Stefan Behnel

Yuzhi Xu schrieb am 23.08.2015 um 08:10:
 I find out that python's VM seems to be very unfriendly with CPU-Cache.
 see:
 http://stackoverflow.com/questions/32163585/how-to-handle-cpu-cache-in-python-or-fastest-way-to-call-a-function-once
 http://stackoverflow.com/questions/32153178/python-functionor-a-code-block-runs-much-slower-with-a-time-interval-in-a-loop
 
 for example:
 ***
 import time
 a = range(500)
 
 sum(a)
 
 for i in range(100): #just to create a time interval, seems this disturb 
 cpu cache?
 pass
 
 
 st = time.time()
 sum(a)
 print (time.time() - st)*1e6
 
 *
 time: 100us
 
 
 another case:
 *
 import time
 a = range(500)
 
 for i in range(10):
 st = time.time()
 sum(a)
 print (time.time() - st)*1e6
 
 *
 time:~ 20us
 
 
 we can see when running frequently, the code becomes much faster.

That does not seem like a straight forward deduction. Especially the
interpretation that the CPU caching behaviour is to blame here seems rather
far fetched.

My guess is that it rather has to do with CPython's internal object caching
or something at that level. However, given the absolute timings above, I
wouldn't bother too much finding it out. It's unlikely to hurt real-world
code. (And in fact, the more interesting case where things are happing
several times in a row rather than being a negligible constant one-time
effort seems to be substantially faster in your timings. Congratulations!)


 is there a solution?

Is there a problem?

Stefan


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Re: how to handle cpu cache in python ( or fastest way to call a function once)

2015-08-23 Thread Steven D'Aprano

On Sun, 23 Aug 2015 10:07 pm, Vladimir Ignatov wrote:

 Hi,
 
 for i in range(100): #just to create a time interval, seems this
 disturb cpu cache?
 pass
 
 Python interpreter consumes memory quite extensively because
 everything is object.  So constructions like:
 
 range(100):
 
 _take_ memory.  Additionally it will trigger garbage collecting code
 on deallocation time so expect even more delay.

Normally you would be correct, but as my timing results show, using xrange
instead of range does not make any difference.

Whatever is going on here, it isn't as simple as range(100) builds a
giant list.



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Steven

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Is this the way to go with SQLite

I understood that with sqlite3 in Python you can not use prepared
statements. Below the way I solved this.

Also an URL is unique, so I need to check that if it is found, the
values are the same as the ones I wanted to insert.

This is my code.

select_url  = '''SELECT year
 ,  month
 ,  description
 FROM   LINKS
 WHERE  URL = ?'''
year= 2015
month   = 8
for link in links:
description = link[0]
url = link[1]
url_values  = c.execute(select_url, [url]).fetchall()
if len(url_values) == 0:
print('Adding {0}'.format(link))
c.execute('''INSERT INTO links
 (year, month, description, URL)
 VALUES
 (?, ?, ?, ?)
  ''',
  [year, month, description, url])
else:
to_insert   = (year, month, description)
found   = url_values[0]
if found != to_insert:
print('For {0} found {1} instead of {2}'.format(url, found, 
to_insert))


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Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof
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[issue24912] The type of cached objects is mutable

2015-08-23 Thread Mark Shannon


Mark Shannon added the comment:

If there is another issue for this, then it doesn't seem to be a release 
blocker. I think it should be.

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Re: Sometimes bottle takes a lot of time

2015-08-23 Thread Johannes Bauer

On 23.08.2015 18:47, Michael Torrie wrote:

 Since this is an ajax thing, I can entirely
 understand that Firefox introduces random delays.  Practically all
 ajax-heavy sites I've ever used has had random slowdowns in Firefox.

This would imply that random six-second delays have somehow passed the
Firefox QA effortlessly. It's something that is entirely possible, but
also something that I would consider magnitudes less likely than other
explanations. Six seconds is *huge* for regular web applications.

 Name resolution could be an issue, but the script he wrote to simulate
 the browser requests does not show the slowdown at all.  Firefox could
 be doing name resolution differently than the rest of the system and
 Chrome of course, which wouldn't surprise me as Firefox seems to more
 and more stupid stuff.

Proxy settings are another thing that could influence behavior. Maybe
the proxy of his Chrome is differently configured than Firefox and this
is causing issues. SOCKS proxies can emulate DNS as well. So there is a
plethora of possible causes; no need to shift blame before evidence is
presented, no need to jump to conclusions.

 But your bashing on him is inappropriate and
 unhelpful.
[...]
 What is annoying to me is how you have done nothing but jump all over
 him this whole thread, and several other times.  
[...]
 In fact I can find very few of your posts to this list where you
 aren't bashing Cecil in recent months.  This does not reflect well on
 the list community and drives away people who would otherwise want to
 learn Python.

I think you're right about this. I've had some run-in with Cecil some
months ago - don't even remember what it was about. The thing I did
remember was that I was particularly annoyed by the whole discussion
back then. This probably led to me being a lot more agressive in my
choice of tone than I should have been.

You're entirely right that this kind of personal feud and immature
mockery is inappropriate for a mailing list and you're also right that
it does create a toxic atmosphere. Since Python is the lanauge I'm most
passionate about a detrimental effect on the Python community is
something that is surely the exact opposite of what I want.

 If Cecil's posts annoy you, please ignore them (I wouldn't even respond
 to this post of yours, but I feel like something has to be said).

I'll follow your advice and thank you for your honest words.

Cheers,
Johannes

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 Zumindest nicht öffentlich!
Ah, der neueste und bis heute genialste Streich unsere großen
Kosmologen: Die Geheim-Vorhersage.
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[issue20851] Update devguide to cover testing from a tarball

2015-08-23 Thread R. David Murray


R. David Murray added the comment:

How to do it is part of PEP 101 (https://www.python.org/dev/peps/pep-0101/).

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[issue17908] Unittest runner needs an option to call gc.collect() after each test


Robert Collins added the comment:

say, something to run a test until failure, or to
watch for reference leaks, or to run tests in multiple processes :-))

I think a few complimentary things.

unittest extensability currently requires a new CLI entry point for each thing. 
I'd like to fix that.

The actual plumbing is fairly extensible, though its not always obvious. I'd 
like to fix that too - without any global state getting involved.

Of the things you mention, running a given command line until failure and 
checking for reference leaks are both straight forward, very common requests 
(as is the gc check) and I'd like to see those implemented as extensions 
shipped in the stdlib.

Running in parallel becomes important when one is doing slow (e.g. functional) 
tests with unittest, and I think thats important to support. It is however much 
harder to do well: some of the current idioms that have snuck in (like the 
handling of stdout/stderr capturing without the buffer flag) are not well 
matched to the needs of reporting on concurrent tests to users. I'm not in any 
way opposed to a good implementation, but it would need to be good I think - 
there's not much point having a poor implementation, given the rich set of 
parallel test runners that are out there that already build on the unittest 
core (green, nose, testrepository just for starters). The only unique audience 
for stdlib test facilities is the stdlib itself and I think a better way to 
solve that is to enable the use of alternative runners for our own tests 
(moving them to be a little cleaner should enable that) - and then the point 
where it matters is really 'when buildbots would be enough faster to make a di
 fference'.

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Re: Canopy editor-Variables browser and help

2015-08-23 Thread breamoreboy

On Saturday, May 2, 2015 at 8:50:22 PM UTC+1, lbertolotti wrote:
 Can I:
 1.Enable a variable browser in Canopy editor similar to the Spyder editor?
 2.Writing a function say log( gives me the function help, but I can't read 
 the whole documentation
 3.Eclipse had a auto-complete, can I enable this in Canopy?
 4.Perhaps I should try using another editor? I was having some problems with 
 Spyder pythonpath...

What do the Canopy docs at http://docs.enthought.com/canopy/ tell you?

If you've used Eclipse why not give PyDev a try?
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[issue22812] Documentation of unittest -p usage wrong on windows.


Robert Collins added the comment:

Thanks for the patch!

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[issue22812] Documentation of unittest -p usage wrong on windows.

2015-08-23 Thread Roundup Robot


Roundup Robot added the comment:

New changeset e285606efb82 by Robert Collins in branch '3.4':
Issue #22812: Fix unittest discovery examples.
https://hg.python.org/cpython/rev/e285606efb82

New changeset 875a851b9d5a by Robert Collins in branch '3.5':
Issue #22812: Fix unittest discovery examples.
https://hg.python.org/cpython/rev/875a851b9d5a

New changeset d9ec88a1e5d6 by Robert Collins in branch 'default':
Issue #22812: Fix unittest discovery examples.
https://hg.python.org/cpython/rev/d9ec88a1e5d6

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[issue24919] Use user shell in subprocess

2015-08-23 Thread Jan Studený


New submission from Jan Studený:

According to POSIX specification the pathname of user shell is stored in SHELL 
(environmental variable, see 
http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08) 
so I think that is good idea to use that pathname instead of hardcoded one.
Change is only in one line of subprocess package to use SHELL environmental 
variable and use hardcoded shell pathname as fallback.

lines 1431-1433
```
if shell:
args = [/bin/sh, -c] + args
if executable:
```

to

```
if shell:
args = [os.environ.get(SHELL,/bin/sh), -c] + args
if executable:
```

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messages: 249023
nosy: Jan Studený
priority: normal
severity: normal
status: open
title: Use user shell in subprocess
type: behavior
versions: Python 2.7, Python 3.2, Python 3.3, Python 3.4, Python 3.5

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Re: Canopy editor-Variables browser and help

2015-08-23 Thread lbertolotti via Python-list

Anyone?
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Re: Sometimes bottle takes a lot of time

2015-08-23 Thread Ben Finney

Johannes Bauer dfnsonfsdu...@gmx.de writes:

 You're entirely right that this kind of personal feud and immature
 mockery is inappropriate for a mailing list and you're also right that
 it does create a toxic atmosphere. Since Python is the lanauge I'm
 most passionate about a detrimental effect on the Python community is
 something that is surely the exact opposite of what I want.
[…]

 I'll follow your advice and thank you for your honest words.

Thank you for publicly acknowledging this, and for taking responsibility
for positive change. This is essential to keeping our community healthy.

-- 
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  `\   —Melvin Kranzberg's First Law of Technology |
_o__)  |
Ben Finney

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Re: Canopy editor-Variables browser and help

2015-08-23 Thread Chris Angelico

On Mon, Aug 24, 2015 at 8:09 AM, lbertolotti via Python-list
python-list@python.org wrote:
 Anyone?

When you post a follow-up like this, it helps to provide some context.
Fortunately for you, I have a threaded email client, but not everyone
does - and not everyone was subscribed to the list when you first
posted.

If you're having difficulties with Canopy, you may do better on a
specific Canopy mailing list. I, for one, have no experience with it,
and can't advise.

ChrisA
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[issue23839] Clear caches after every test


Robert Collins added the comment:

Ok, so this is still in the noise space - it might be useful, it might not. Do 
we have reports of machines failing to run the test suite (that are also 
usefully big enough to compile Python and use it)?

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[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

2015-08-23 Thread eryksun


eryksun added the comment:

The 3.5 build uses MSVC 14 (VS 2015):

https://docs.python.org/3.5/using/windows.html#compiling-python-on-windows
https://hg.python.org/cpython/file/3.5/PCbuild/readme.txt

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[issue24193] Make LOGGING_FORMAT of assertLogs configurable


Robert Collins added the comment:

Parameters please, TestCase has nothing to do with this - it really shouldn't 
even have the method.

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[issue24168] Unittest discover fails with namespace package if the path contains the string same as the module name


Changes by Robert Collins robe...@robertcollins.net:


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[issue24918] Docs layout bug

2015-08-23 Thread Carol Willing


Carol Willing added the comment:

The highlighting of code box extends beyond the bounds of the box to the far 
right of the page. A screenshot is attached as an example. The behavior occurs 
on all versions (3.2+, 2.7.x) except 2.6.

Thanks for reporting this issue.

--
nosy: +willingc
stage:  - needs patch
type:  - behavior
versions: +Python 3.2, Python 3.3, Python 3.4, Python 3.5, Python 3.6
Added file: http://bugs.python.org/file40235/Screenshot 2015-08-23 16.55.34.png

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[issue20851] Update devguide to cover testing from a tarball


Robert Collins added the comment:

Possibly silly q: how does one /make/ a Python release tarball? 'make dist' 
which is the autoconf standard complains that it has no such target...

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[issue24919] Use user shell in subprocess

2015-08-23 Thread R. David Murray


R. David Murray added the comment:

Thanks for the suggestion, but that would make programs using subprocess 
non-portable.  There is an open issue to use the *default* shell instead of 
hard coding it (because the sh-alike is not at /bin/sh on, eg, Android), but 
using the user shell would break lots of programs.  Your suggestion was brought 
up by a core dev (and rejected) in that issue (issue 16255)

--
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resolution:  - duplicate
stage:  - resolved
status: open - closed
superseder:  - subrocess.Popen needs /bin/sh but Android only has 
/system/bin/sh

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[issue24633] README file installed into site-packages conflicts with package named readme


Robert Collins added the comment:

Applied to 3.6 only (since I don't want to disrupt the 3.5 release train, and 
think that making packagers adjust on a point release would be mean).

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[issue19469] Duplicate namespace package portions (but not on Windows)

2015-08-23 Thread Caio Ariede


Caio Ariede added the comment:

I tried to reproduce it using Python 3.4.3 and 3.4.2. No luck.

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status: pending - open

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[issue22812] Documentation of unittest -p usage wrong on windows.

2015-08-23 Thread Roundup Robot


Roundup Robot added the comment:

New changeset 3256764fadae by Robert Collins in branch '2.7':
Issue #22812: Fix unittest discovery examples.
https://hg.python.org/cpython/rev/3256764fadae

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[issue2786] Names in traceback should have class names, if they're methods


Changes by Robert Collins robe...@robertcollins.net:


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[issue24918] Docs layout bug

2015-08-23 Thread asldkjfn


New submission from asldkjfn:

Green bars cover yellow text box. 
https://docs.python.org/2/faq/windows.html

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messages: 249018
nosy: docs@python, reag
priority: normal
severity: normal
status: open
title: Docs layout bug
versions: Python 2.7

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asyncio, coroutines, etc. and simultaneous execution

2015-08-23 Thread Charles Hixson

If I understand correctly asyncio, coroutines, etc. (and, of course,
Threads) are not simultaneously executed, and that if one wants that one
must still use multiprocessing. But I'm not sure. The note is still
there at the start of threading, so I'm pretty sure about that one.

The requirement that coroutines always be awaited seems to confirm this,
but doesn't really say so explicitly. And the concurrent.futures can
clearly be either, depending on your choices, but the chart in
18.5.3.1.3 Example: Chain coroutines is of a kind that I am more
familiar with in the context of multiprocessing. (E.g., the only gap in
the chart, which extends across all headings is when a result is being
waited for during a sleep.) For threaded execution I would expect there
to be a gap whenever processing is shifted from one column to another.

If someone has authority to edit the documentation a comment like:

If you want your application to make better use of the computational
resources of multi-core machines, you are advised to use multiprocessing
https://docs.python.org/3.5/library/multiprocessing.html#module-multiprocessing
or concurrent.futures.ProcessPoolExecutor
https://docs.python.org/3.5/library/concurrent.futures.html#concurrent.futures.ProcessPoolExecutor.
However, threading is still an appropriate model if you want to run
multiple I/O-bound tasks simultaneously.

(to quote from the threading documentation) would be helpful at or very
near the top of each of the appropriate modules. It would also be
useful if the modules that were definitely intended to result in
simultaneous execution, when feasible, were so marked quite near the top.

OTOH, I may be mistaken about coroutines. I haven't been able to tell.

P.S.: I do note that the threading comment was a *CPython
implementation detail:*, and not a part of the Python specifications.
But CPython is, I believe, a sufficiently dominant implementation that
such details are quite important.
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[issue20851] Update devguide to cover testing from a tarball

2015-08-23 Thread Larry Hastings


Larry Hastings added the comment:

To make the tarballs, I use the release.py script from here:

https://hg.python.org/release

and run release.py --export versionnumber.  I haven't peeked inside the 
black box to see how the sausage is made.

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Re: asyncio, coroutines, etc. and simultaneous execution

2015-08-23 Thread Akira Li

Charles Hixson charleshi...@earthlink.net writes:

If I understand correctly asyncio, coroutines, etc. (and, of course,
Threads) are not simultaneously executed, and that if one wants that
one must still use multiprocessing. But I'm not sure. The note is
still there at the start of threading, so I'm pretty sure about that
one.

Due to GIL (used by CPython, Pypy, not used by Jython, IronPython,
pypy-stm) only one thread executes Python bytecode at a time. GIL can be
released on I/O or in a C extension such as numpy, lxml, regex. It is
true for any Python module or concept you use.

Unrelated: use concurrent and parallel execution instead of
simultaneously executed.

Parallelism might make a program faster (it implies that hardware
supports it).

Concurrency is a way to structure the code. The same concurrent program
can run in parallel and without parallelism.

Recommended: Concurrency is not Parallelism
(it's better!) talk by Rob Pike's talk
http://stackoverflow.com/questions/1050222/concurrency-vs-parallelism-what-is-the-difference

The requirement that coroutines always be awaited seems to confirm
this, but doesn't really say so explicitly. And the concurrent.futures
can clearly be either, depending on your choices, but the chart in
18.5.3.1.3 Example: Chain coroutines is of a kind that I am more
familiar with in the context of multiprocessing. (E.g., the only gap
in the chart, which extends across all headings is when a result is
being waited for during a sleep.) For threaded execution I would
expect there to be a gap whenever processing is shifted from one
column to another.

If someone has authority to edit the documentation a comment like:

Anybody can suggest a patch
https://docs.python.org/devguide/docquality.html

If you want your application to make better use of the computational
resources of multi-core machines, you are advised to use
multiprocessing
https://docs.python.org/3.5/library/multiprocessing.html#module-multiprocessing
or concurrent.futures.ProcessPoolExecutor
https://docs.python.org/3.5/library/concurrent.futures.html#concurrent.futures.ProcessPoolExecutor.
However,
threading is still an appropriate model if you want to run multiple
I/O-bound tasks simultaneously.

(to quote from the threading documentation) would be helpful at or
very near the top of each of the appropriate modules. It would also
be useful if the modules that were definitely intended to result in
simultaneous execution, when feasible, were so marked quite near the
top.

It is not necessary that multiprocessing will make your code faster on a
multi-core machine. It may make it slower depending on the task.

Performance optimization is a vast topic. Short remarks such as you've
suggested are likely misleading.

OTOH, I may be mistaken about coroutines. I haven't been able to tell.

Many cooperative multitasking implementations use a *single*
thread. There is a way to offload blocking code e.g.,
loop.run_in_executor() in asyncio.

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[issue24055] unittest package-level set up tear down module