Re: [Python-Dev] Small lament...

[Eric Fahlgren]

Oh, man, it has been a while.  The last one I remember is PEP 404 (if you
can find it :) ), dated 2011 and it wasn't an April Fool's...

On Sat, Apr 1, 2023 at 11:23 AM Skip Montanaro 
wrote:

> Just wanted to throw this out there... I lament the loss of waking up on
> April 1st to see a creative April Fool's Day joke on one or both of these
> lists, often from our FLUFL... Maybe such frivolity still happens, just not in
> the Python ecosystem? I know you can still import "this" or
> "antigravity", but those are now old (both introduced before 2010). When
> was the last time a clever easter egg was introduced or an April Fool's Day
> joke played?
>
> ¯\_(ツ)_/¯
>
> Skip
>
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[issue41515] typing.get_type_hints generates KeyError

[Eric Fahlgren]

New submission from Eric Fahlgren :

Windows 10 Pro 64
Python 3.8.3 64
wxPython 4.1.0

It appears that there are synthetic classes in the mro, which don't appear in 
the type's namespace, raising KeyError when encountered.  From reading the 
function's doc and source, it looks like it should handle this internally and 
return a valid dict (possibly empty), and not raise KeyError.

>>> import typing, wx
>>> typing.get_type_hints(wx.Window)'
Traceback (most recent call last):
  File "", line 1, in 
  File "C:\Program Files\Python38\lib\typing.py", line 1223, in get_type_hints
base_globals = sys.modules[base.__module__].__dict__

>>> wx.Window.mro()
[, , , , , , , 
]

KeyError: 'sip'

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components: Library (Lib)
messages: 375111
nosy: eric.fahlgren
priority: normal
severity: normal
status: open
title: typing.get_type_hints generates KeyError
versions: Python 3.8

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[issue39629] inspect.signature fails on math.hypot

[Eric Fahlgren]

New submission from Eric Fahlgren :

Python 3.8's new math.hypot function also appears to suffer from the same issue 
as math.log:

>>> import math, inspect
>>> inspect.signature(math.hypot)
Traceback (most recent call last):
  File "", line 1, in 
  File "C:\Program Files\Python38\lib\inspect.py", line 3093, in signature
return Signature.from_callable(obj, follow_wrapped=follow_wrapped)
  File "C:\Program Files\Python38\lib\inspect.py", line 2842, in from_callable
return _signature_from_callable(obj, sigcls=cls,
  File "C:\Program Files\Python38\lib\inspect.py", line 2296, in 
_signature_from_callable
return _signature_from_builtin(sigcls, obj,
  File "C:\Program Files\Python38\lib\inspect.py", line 2107, in 
_signature_from_builtin
raise ValueError("no signature found for builtin {!r}".format(func))
ValueError: no signature found for builtin 

Possibly related to issue29299?

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nosy: eric.fahlgren
priority: normal
severity: normal
status: open
title: inspect.signature fails on math.hypot
type: behavior
versions: Python 3.8

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Re: [Scons-dev] SCons 3.1.2 Released

[Eric Fahlgren]

On Mon, Dec 16, 2019 at 7:02 PM Bill Deegan 
wrote:

> - EXPERIMENTAL NEW FEATURE: Enable caching MSVC configuration
>   If SCONS_CACHE_MSVC_CONFIG shell environment variable is set,
>   SCons will cache the results of past calls to vcvarsall.bat to
>   a file; integrates with existing memoizing of such vars.
>   On vs2019 saves 5+ seconds per SCons invocation, which really
>   helps test suite runs.
>

Thanks a bunch for this one!  Our bare, no-target 'scons' invocation is
down to about 0.8 seconds now, and we can do a single DLL build in ~2.5 s,
which makes things very snappy indeed.
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[issue35785] argparse crashes in gettext when processing missing arguments

[Eric Fahlgren]

Eric Fahlgren  added the comment:

Thanks, I installed 3.7.2 on one of our non-production machines and it appears 
that gettext has been fixed, so I'm closing this.

> python -V
Python 3.7.2
> python bpo35785.py --foo
usage: bpo35785.py [-h] [--foo FOO]
bpo35785.py: error: argument --foo: expected one argument

--
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stage:  -> resolved
status: open -> closed

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[issue35785] argparse crashes in gettext when processing missing arguments

[Eric Fahlgren]

Eric Fahlgren  added the comment:

After a bit more digging, it's a side effect of having the locale set with 
'Plural-Forms'.  I've attached the resulting .mo file, but since it's a binary, 
I'm not sure it will work cross-platform, so here's how to recreate it.

> cat en_US/LC_MESSAGES/foo.po
msgid ""
msgstr "Plural-Forms: nplurals=2; plural=(n != 1);\n"

> python /Python37/Tools/i18n/msgfmt.py en_US/LC_MESSAGES/foo.po
> ll en_US/LC_MESSAGES/
-rwx--+ 1 efahlgren Domain Users 89 2019-01-19 14:36 foo.mo*
-rw-r--r--+ 1 efahlgren Domain Users 69 2019-01-19 14:34 foo.po

Then you can reproduce with some setup in your script:

import os
import gettext
import argparse

os.putenv('LANG', 'en_US')  # Just to make sure.
gettext.bindtextdomain('foo', '.')
gettext.textdomain('foo')

p = argparse.ArgumentParser()
p.add_argument('--foo', nargs=None)
p.parse_args()

--
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[issue35785] argparse crashes in gettext when processing missing arguments

[Eric Fahlgren]

New submission from Eric Fahlgren :

When argparse is configured with an option that takes arguments, then the 
script is invoked with the switch but no arguments, a nonsensical exception is 
raised during gettext processing.

In the 3.7.1 source, the error is at line 2077 of argparse.py, where 
'action.nargs' is not an integer as expected by 'ngettext', but one of None, 
'*' or '?':

default = ngettext('expected %s argument',
   'expected %s arguments',
   action.nargs) % action.nargs
msg = nargs_errors.get(action.nargs, default)

Fix should be pretty trivial, swap the two lines and if 'get' produces None, 
only then compute the default.

  File "C:\Program Files\Python37\lib\argparse.py", line 1749, in parse_args
args, argv = self.parse_known_args(args, namespace)
  File "C:\Program Files\Python37\lib\argparse.py", line 1781, in 
parse_known_args
namespace, args = self._parse_known_args(args, namespace)
  File "C:\Program Files\Python37\lib\argparse.py", line 1987, in 
_parse_known_args
start_index = consume_optional(start_index)
  File "C:\Program Files\Python37\lib\argparse.py", line 1917, in 
consume_optional
arg_count = match_argument(action, selected_patterns)
  File "C:\Program Files\Python37\lib\argparse.py", line 2079, in 
_match_argument
action.nargs) % action.nargs
  File "C:\Program Files\Python37\lib\gettext.py", line 631, in ngettext
return dngettext(_current_domain, msgid1, msgid2, n)
  File "C:\Program Files\Python37\lib\gettext.py", line 610, in dngettext
return t.ngettext(msgid1, msgid2, n)
  File "C:\Program Files\Python37\lib\gettext.py", line 462, in ngettext
tmsg = self._catalog[(msgid1, self.plural(n))]
  File "", line 4, in func
  File "C:\Program Files\Python37\lib\gettext.py", line 168, in _as_int
(n.__class__.__name__,)) from None
TypeError: Plural value must be an integer, got NoneType

--
components: Library (Lib)
messages: 334065
nosy: eric.fahlgren
priority: normal
severity: normal
status: open
title: argparse crashes in gettext when processing missing arguments
versions: Python 3.7

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[issue35785] argparse crashes in gettext when processing missing arguments

[Eric Fahlgren]

Change by Eric Fahlgren :


--
type:  -> crash

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[issue34252] Bunch of path leaks on Python 3.7 on Release

[Eric Fahlgren]

Eric Fahlgren  added the comment:

I believe that the CL command line switch is /FC, not /FP:

https://msdn.microsoft.com/en-us/library/027c4t2s.aspx

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[issue33656] IDLE: Turn on DPI awareness on Windows

[Eric Fahlgren]

Eric Fahlgren  added the comment:

So maybe add the dpiAware and dpiAwareness settings to the manifest for just 
Windows' pythonw.exe and leave the python.exe console interpreter alone?  I'm 
going to guess that the pythonw.exe manifest already has some settings related 
to its unique status that align with this.

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[issue33656] IDLE: Turn on DPI awareness on Windows

[Eric Fahlgren]

Eric Fahlgren  added the comment:

https://msdn.microsoft.com/en-us/library/windows/desktop/mt748620(v=vs.85).aspx 
gives the syntax for adding dpiAwareness to the Windows manifest.

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[issue26698] Tk DPI awareness

[Eric Fahlgren]

Eric Fahlgren  added the comment:

I used the default Application setting.

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[issue26698] Tk DPI awareness

[Eric Fahlgren]

Eric Fahlgren  added the comment:

Still blurry with 3.6.5 on Win 10 with a 2560x1600 monitor at 125% scaling (I 
compared it to 2.7.15, they looked identical).  If I go to the Windows 
properties for pythonw.exe and turn on "Override high DPI scaling behavior" 
it's nice and sharp.

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Re: [wxPython-dev] wxPython 4.0.0 final

[Eric Fahlgren]

Excellent work, Robin (and other committers)!  Thanks for all your
continued efforts to keep wxPython alive and growing.

On Wed, Jan 31, 2018 at 5:37 PM, Robin Dunn  wrote:

>
> Announcing wxPython 4.0.0
> =
>
> PyPI:   https://pypi.python.org/pypi/wxPython/4.0.0
> Extras: https://extras.wxPython.org/wxPython4/extras/
> Pip:``pip install wxPython==4.0.0``
>
> Changes in this release include the following:
>
> * Fixes in wx.aui to properly transfer ownership of the menubar, and
>   also some tweaks in the AUI_MDI sample in the demo. (#540)
>
> * Added a wx.BUILD_TYPE value to distinguish between development,
>   snapshot, and release builds. The value is also appended to
>   wx.PlatformInfo. (Thanks Mesalu!)
>
> * Fix crash when trying to fetch multiple items from a composite data
>   object in wx.DropTarget.OnData. (#550) Also fixed the
>   CustomDragAndDrop sample to not fail on Python 2.7.
>
> * Add ability for wxArray wrappers to return a copy of the item in the
>   ``__getitem__`` method. This solves problems where an array that is
>   the return value of some method call is indexed immediately and a
>   reference to the array is not held, which could result in garbage
>   values for the indexed item. Currently this is turned on for just
>   GridCellCoordsArray, but others can be switched in the future if
>   needed. (#297)
>
> * Add missing ``wx.GetLocale`` function. (#572)
>
> * Add methods to wx.TextCtrl for output "file-like"
>   compatibility. (#578)
>
> * Fix object ownership issue for menus added to toolbar items. (#580)
>
> * Updated SIP to version 4.19.5. One of the new features of this
>   version is that integer overflows are no longer silently truncated
>   and ignored. In other words, if a wrapped API has a parameter that
>   is a C int type, and you pass a value that is larger than what will
>   fit in that type of integer then an OverflowError exception will be
>   raised.
>
> * Fixed wx.richtext.RichTextBuffer.GetExtWildcard to return a tuple of
>   2 values, as was done in Classic. (#594)
>
> * Various fixes in UltimateListCtrl, HyperTreeList and
>   CheckListCtrlMixin.  (#592, #349, #612)
>
> * Fixes in TextEditMixin to ensure that the new value is passed in the
>   event. (#605)
>
> * Fix comparing DataViewItem and TreeListItem objects with
>   None. (#595)
>
> * Fix event type name in wx/lib/sheet.py (#613)
>
> * The wx.MessageDialog methods which take ButtonLabel parameters are
>   now able to accept either strings or stock IDs. (#607, #276)
>
> * Fix wx.EvtHandler.Unbind to work correctly when specifying the
>   handler and it is a bound method. (#624)
>
> * Fix OGL's ShapeCanvas to draw properly when the window is scrolled,
>   and to also adjust the mouse coordinates, etc. (#635)
>
> * Set a default background color for the generic buttons. (#651)
>
> * Fixed HtmlWindow's OnFoo virtual methods so calls to them are
>   propagated to the Python class. (#642)
>
> * Fixed wx.CallLater to explicitly hold a reference instead of
>   depending on an uncollectable cycle to keep the instance
>   around. Like before the cycle is broken and the saved reference is
>   deleted after the timer expires and the callable has been
>   called. (#457)
>
> * Although it's more or less just an implementation detail, add
>   wrappers for wx.aui.AuiTabCtrl so references to it will get the
>   correct type. (#664)
>
> * List-like wrapper classes generated for accessing wxLists and
>   wxArrays now support reverse indexing. (#669) For example::
>
>   child = panel.GetChildren()[-1]
>
>
> * Ported some of the classes in Classic's gizmos module from C++ to
>   Python, including LEDNumberCtrl, DynamicSashWindow, and
>   TreeListCtrl. The classes are now located in the wx.lib.gizmos
>   package, with a compatibility module at the old wx.gizmos
>   location. Please note that this TreeListCtrl class is a very
>   different implementation than wx.dataview.TreeListCtrl, although
>   there is some overlap in purpose. In addition, the new TreeListCtrl
>   class is not actually a port from the old gizmos.TreeListCtrl but
>   rather just a thin layer around AGW's HyperTreeList. This means that
>   if you are using a non- default style flag you'll need to pass it to
>   the agwStyle parameter instead of the style parameter.
>
> * Fix crash when deleting all wx.dataview.TreeListCtrl items with
>   wxGTK3.  (#679, #704)
>
> * Fix displaying '&' in the label of wx.RadioBox on GTK. (#39)
>
> * Fix problems of the wrong C++ method being called in
>   wx.ProgressDialog on MS Windows. (#701)
>
> * Fixed how the scrollbar events are captured in DynamicSashWindow in
>   order to fix regression in the sample. (#687)
>
> * Allow extra CLI args to be passed to build.py by setting
>   WXPYTHON_BUILD_ARGS in the environment.
>
> * Added context manager methods to wx.DC that explicitly destroys the
>   C++ part of the DC upon exit. Using DCs as context managers is not
>   

[issue1495754] os.listdir(): inconsistent behavior with trailing spaces

[Eric Fahlgren]

Eric Fahlgren added the comment:

Would it be appropriate to make a comment about this Windows bug in both 
os.stat and os.path.exists documentation?  I just stumbled upon it 
independently (both Win7 and 10, both Py 2.7 and 3.6) with nearly the same 
incantation that Kenneth reported over 10 years ago (exists check success, 
followed by scandir failure).

[My workaround was to append os.sep to the directory spec:
  os.path.exists(newdir+os.sep) -> False
]

Clearly this behavior is not going away, so it should at least be mentioned 
somewhere more prominently than on a decade old BPO item...

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[issue29282] Fused multiply-add: proposal to add math.fma()

[Eric Fahlgren]

Changes by Eric Fahlgren <ericfahlg...@gmail.com>:


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[issue23407] os.walk always follows Windows junctions

[Eric Fahlgren]

Eric Fahlgren added the comment:

> # Junctions are not recognized as links.
> self.assertFalse(os.path.islink(self.junction))

If the above comment is intended as a statement of fact, then it's inconsistent 
with the implementation of Py_DeleteFileW ( 
https://hg.python.org/cpython/file/v3.6.0/Modules/posixmodule.c#l4178 ).

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Thanks, Serhiy.  I sort of figured that it would get fixed with the
wordcode rework, and was going to verify that it was when 3.6 settled down.

On Sun, Jun 5, 2016 at 8:30 AM, Serhiy Storchaka <rep...@bugs.python.org>
wrote:

>
> Serhiy Storchaka added the comment:
>
> This bug was fixed in issue26881 with similar patch. Sorry, I didn't know
> about this issue. Your patches look good. In any case thank you for your
> effort.
>
> --
> nosy: +serhiy.storchaka
> resolution:  -> out of date
> stage:  -> resolved
> status: open -> closed
> superseder:  -> modulefinder should reuse the dis module
>
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[issue27129] Wordcode, part 2

[Eric Fahlgren]

Changes by Eric Fahlgren <ericfahlg...@gmail.com>:


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[issue22893] Idle: __future__ does not work in startup code.

[Eric Fahlgren]

Changes by Eric Fahlgren <ericfahlg...@gmail.com>:


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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Barun, take a look at the latest version of the testfindlabels.py, see what you 
think.  If it works for you, maybe move the test function into 
Lib/test/test_dis.py as part of the standard dis module tests.  Still need to 
look at the code that's being tested and find out what cases could cause 
problems and then augment the test to make sure it covers those.

--
Added file: http://bugs.python.org/file42065/dis_with_code_scanner.diff

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Oops, wrong/bad patch, delete line 310 "arg = None" in _get_instruction_bytes...

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Two things:

1) Verified this has always been a problem and still is in the development 
branch, so I added 2.7 and 3.6 to the versions list.

2) Couldn't tolerate the duplicate code handling the extended args operator, so 
in the interests of DRY, I moved the code scanner to a generator function (see 
attached dis_with_code_scanner.diff).

The patch is definitely not required to fix this bug, but it does isolate the 
original problem area to just one piece of code.

Could we get a get a quick review from a core dev saying either "go with 
Barun's less invasive preliminarypatch.diff" or "go with Eric's greater-churn 
dis_with_code_scanner.diff patch?"

(We still need to flesh out the testing a bit, so don't call us, we'll call 
you. :) )

--
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Added file: http://bugs.python.org/file42047/dis_with_code_scanner.diff

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

I just remembered that code can have more than one (up to three?) EXTENDED_ARG 
operators before the real opcode, so I added that generalization to build code 
around the args list...

--
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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Oh, don't worry about time between responses, we all have lives (well, some of 
us anyhow :) ).

After looking at Lib/test/test_dis.py, I think it's just an oversight that 
there is no specific findlabels test (it's tested implicitly by ``dis.dis`` 
after all), and it would be good thing for you to add one.  The obvious place 
seems like a new method at the bottom of the ``DisTests`` class, but we'll have 
to rely on (probably) Yury to make that call.

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Lookin' good so far.  How about we try it on all the opcodes that have 
arguments?

See attached example for which I can see two obvious improvements:
1) It could be improved by taking apart that "args" list and using it to 
synthesize "sample_code" rather than having to hand duplicate the values in two 
places, albeit with different byte order.
2) Likewise, my hard-coded "offsets" table is pretty awful. :)

Also, is there already a test for the dis module in which you could just add 
this as a case?

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Added file: http://bugs.python.org/file42039/testfindlabels.py

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

The findlabels function takes a bytecode array of type bytes, usually the
actual code from a function.  My original test case uses the full Python
compiler from source code to a CodeType object to create the bytecodes
(plus all that other stuff that makes up a function), then extracts just
the interesting part and passes that into findlabels.

The good part is that you can pretend you're the compiler by just putting
the correct bytes into a array and feed it into the various dis functions.
The EXTENDED_ARG operator plays with the operand of the succeeding
instruction, everything else either doesn't have an argument or has two
bytes.

Here's a real test case, I don't know how you write unit tests for the
stdlib, but you can compare the output of the findlabels call with a known
value, and that should get you pretty close.

from opcode import *
code = bytes(
chr(opmap["JUMP_FORWARD"]) + chr(0) + chr(0) +
chr(EXTENDED_ARG) + chr(1) + chr(0) +
chr(opmap["JUMP_FORWARD"]) + chr(0) + chr(0) +
chr(opmap["RETURN_VALUE"]),
encoding="latin-1"
)
import dis
dis.dis(code)
print(dis.findlabels(code))
if dis.findlabels(code) == [0x+3, 0x0001+9]:
print("Test passed")

Take a look in the stdlib opcode.py and find the various "JUMP" operators,
those are the guys we care about for this.  Try out a bunch of cases by
augmenting the above definition of "code" and you'll soon get a feel for
what's going on.

As real, executable bytecode the above is of course non-sensical, but for a
test, it's great because you can predict exactly what should be produced.
​

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Well, now that I'm thinking about it, you could synthesize a bytecode stream 
trivially and have a much better test.  This is completely off the top of my 
head, so take it is guaranteed to (probably) not work as written, but it should 
get you started:

from opcodes import *
import dis
bytecode = (
chr(EXTENDED_ARG) + chr(1) + chr(0) + 
chr(JUMP_IF_TRUE_OR_POP) + chr(0) + chr(0)
)
print(dis.findlabels(bytecode))

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

Our paths crossed, I don't know exactly how you'd add a test case for this, 
maybe construct the monster function in a string, eval the string, the use the 
synthesized function in dis.findlabels?

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

Eric Fahlgren added the comment:

My test case:

def long():
z = a = b = c = d = e = f = g = h = 1
while x:
x = x if x and x or not x else x
above line repeated 2999 more times

import dis
print(dis.findlabels(long.__code__.co_code)[:10])

Buggy output:
[35510, 35509, 62, 69, 78, 81, 93, 100, 109, 112]

Correct output:
[101046, 101045, 62, 69, 78, 81, 93, 100, 109, 112]

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[issue26448] dis.findlabels ignores EXTENDED_ARG

[Eric Fahlgren]

New submission from Eric Fahlgren:

When trying out dis.dis on some synthetically long functions, I noted that 
spurious branch targets were being generated in the output.  First one is at 
address 8:

157   0 LOAD_CONST   1 (1)
  3 DUP_TOP
  4 STORE_FAST   0 (z)
  7 DUP_TOP
>>8 STORE_FAST   1 (a)
 11 DUP_TOP

I dug into findlabels and notices that it pays no attention to EXTENDED_ARG.  
The fix is pretty simple, basically copy pasta from 
dis._get_instructions_bytes, at line 369, in the 3.5.1 release code add all the 
"extended_arg" bits:

extended_arg = 0
while i < n:
op = code[i]
i = i+1
if op >= HAVE_ARGUMENT:
arg = code[i] + code[i+1]*256 + extended_arg
extended_arg = 0
i = i+2
if op == EXTENDED_ARG:
 extended_arg = arg*65536
label = -1

--
components: Library (Lib)
messages: 260913
nosy: eric.fahlgren
priority: normal
severity: normal
status: open
title: dis.findlabels ignores EXTENDED_ARG
type: behavior
versions: Python 3.5

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[issue26110] Speedup method calls 1.2x

[Eric Fahlgren]

Changes by Eric Fahlgren <ericfahlg...@gmail.com>:


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[issue26252] Add an example to importlib docs on setting up an importer

[Eric Fahlgren]

Changes by Eric Fahlgren <ericfahlg...@gmail.com>:


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