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Title: IDLE does not supply a default ext of .py on Windows or OS X for new file saves
Type: enhancement Stage: resolved
Components: IDLE Versions: Python 2.7
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: terry.reedy Nosy List: Saimadhav.Heblikar, ajaksu2, amaury.forgeotdarc, geon, gpolo, ned.deily, python-dev, roger.serwy, terry.reedy
Priority: normal Keywords: patch

Created on 2009-01-04 15:16 by geon, last changed 2022-04-11 14:56 by admin. This issue is now closed.

File name Uploaded Description Edit
defaultextension.patch amaury.forgeotdarc, 2009-05-13 17:00
fix_defaultextension.diff gpolo, 2009-08-01 20:45
issue4832.diff roger.serwy, 2011-12-14 18:49 review
issue4832_rev1.patch roger.serwy, 2012-07-09 21:48 review
issue4832_rev2.patch ned.deily, 2012-07-10 03:52 review
Messages (27)
msg79062 - (view) Author: Pavel Kosina (geon) Date: 2009-01-04 15:16
There should not be necessity to write filename *with extension* at the
saving dialog. It should be enough, at least on Windows, to put there
just "hello" and get "". It is really complication especially
for beginners. If they, as they are used to from another programs, put
there just "hello", it is saved without extension ".py" what have 2
result: they cannot see any icons at that file and they are not able to
run in, cause python.exe is bind with ".py".

Hoping its not duplicate I haven't found anything like this here.
msg86620 - (view) Author: Daniel Diniz (ajaksu2) * (Python triager) Date: 2009-04-26 22:17
I get the .py automatically on Linux, is this an intended behavior
difference or should this issue be considered a bug instead?
msg87695 - (view) Author: Amaury Forgeot d'Arc (amaury.forgeotdarc) * (Python committer) Date: 2009-05-13 17:00
I think I found the relevant documentation:
On Unix, when typing a filename without extension, the first extension
belonging to the currently selected filetype will be appended to the
filename. On Windows, this is not the case, but one can define a fixed
extension with the -defaultextension option. To get the same behaviour
on Unix, use -defaultextension {}.

I tried to add "", (see attached patch) the problem
is that now it seems impossible to create a file without an extension...
msg87702 - (view) Author: Daniel Diniz (ajaksu2) * (Python triager) Date: 2009-05-13 19:07
Your patch also forces '.py' to any saved file on Linux, but using
'defaultextension = ""' it works correctly here. Does if fix things on
msg87703 - (view) Author: Pavel Kosina (geon) Date: 2009-05-13 19:46
Trying to patch the latest revision 72608 and it didnt work, here on winxp. 

C:\prg\Python30\Lib\idlelib>svn update
Restored ''
At revision 72608.

C:\prg\Python30\Lib\idlelib>patch defaultextension.patch
Hmm...  Looks like a unified diff to me...
The text leading up to this was:
|Index: Lib/idlelib/
|--- Lib/idlelib/   (revision 72282)
|+++ Lib/idlelib/   (working copy)
Patching file using Plan A...
Hunk #1 succeeded at 480 (offset -45 lines).
Hmm...  Ignoring the trailing garbage.

If I do the patch by hand, it works. All files are saved with ext. .py.
When set 'defaultextension = ""', it is save well too, but then IDLE
crashed immediately.
msg91168 - (view) Author: Guilherme Polo (gpolo) * (Python committer) Date: 2009-08-01 20:45
I'm attaching a very similar patch that I tested on Linux and Windows.
It just combines the default behaviour with the details required for
Windows, that is, the default extension is set to '.py' for Windows and
'' elsewhere (the default).
msg91260 - (view) Author: Amaury Forgeot d'Arc (amaury.forgeotdarc) * (Python committer) Date: 2009-08-04 17:47
With this new patch, is it possible to create a file without extension
on Windows?
msg91262 - (view) Author: Guilherme Polo (gpolo) * (Python committer) Date: 2009-08-04 18:05
> With this new patch, is it possible to create a file without extension
> on Windows?

It is tricky but, answering your question, you could enter a name
ending with a period to save without an extension.

It seems this isn't going anywhere then. The default behaviour on
Linux is to get the .py already, so this patch changes nothing there.
On Windows no extension is set by default, and with this patch it is
always .py if no extension is specified.
msg110962 - (view) Author: Tal Einat (taleinat) * (Python committer) Date: 2010-07-20 20:13
On Windows, I can't think of any common reason to want to save a file edited in IDLE without the .py extension. On the other hand, accidentally forgetting the .py extension is annoying, and users have come to expect a default extension being added by applications (e.g. MS Office).

Guilherme's patch (applied manually) works fine here on Windows7. I'm +1 for committing this if it has been tested to work as expected on Linux and OSX.

(minor nit-pick: could use sys.platform.startswith('win') instead of slicing)
msg110964 - (view) Author: Brian Curtin (brian.curtin) * (Python committer) Date: 2010-07-20 20:23
I would forget about slicing or using startswith. "win32" is the platform name for Python on Windows whether or not it's 64-bit (see PC/pyconfig.h), so I'd just check """sys.platform == 'win32'"""
msg110966 - (view) Author: Guilherme Polo (gpolo) * (Python committer) Date: 2010-07-20 20:31
Sorry but this is just bikeshedding, whoever commits can make this change or if it had been committed without this "improvement" then anyone could adjust without needing a new issue.
msg130399 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2011-03-09 02:23
The behavior (for Windows) I expect and would like is that the default extension would be .py, .txt, or nothing, depending on the selection in the 'save as type' box in the SaveAS dialog. (.pyw, being rare, would have to be explicitly typed.) Of course, doubled extensions like should be avoided. I believe other apps on Windows do something like this, but I should check.

I have no idea how the other systems differ.
msg149466 - (view) Author: Roger Serwy (roger.serwy) * (Python committer) Date: 2011-12-14 18:49
I was unable to produce the crash that Pavel described in msg87703.  

Just adding "defaultextension=''" solves this issue for Windows and still preserves the correct behavior on Linux. Amaury's quote of tcl/tk documentation in msg87695 mentions this as well.

I tested this on Linux with 2.7.1 and 3.2 and on Windows Vista using 2.7.1 and 3.2.2. 

Attached is a diff against 3.3a0.
msg165128 - (view) Author: Roger Serwy (roger.serwy) * (Python committer) Date: 2012-07-09 21:48
issue4832_rev1.patch is a complete patch against 3.3.

This is also part of issue13504, "7) ANNOYANCE: It’s too easy to forget the .py extension when saving a file."
msg165135 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2012-07-09 23:29
I tested with defaultextension='' on Windows and it works well. If no extension is entered (no '.' in name), .py or .txt is added for the .py/w and .txt filetype choices. If there is a . in the name, nothing is added. If one wants, one must type the whole name. So typing x.pyw does not get .py added on top of it. This needs to be documented in the Idle help file.

Should the change only be made to 3.3, or also to 3.2/2.7? The old behavior of typing .py still works, so that does not break. Typing no . to get no extension (rare) will break unless one selects '*.* all files' (which one should do anyway as it is standard Windows behavior). I think uniform across versions is better so people who learn leaving out .py on 3.3 can also leave it out in future 2.7 and 3.2, which should come out about the same time as 3.3.0.

Whether just one or two or three versions, how do people used to the old (buggy in my opinion) behavior find out about the change. A splash line on startup "See help for new 'save as' behavior" ?

Anything I should know about *nix or mac behavior, at least for the doc? Ned, does this change work on macs?
msg165147 - (view) Author: Roger Serwy (roger.serwy) * (Python committer) Date: 2012-07-10 02:44
Your description applied to the behavior on Ubuntu 11.04.
msg165154 - (view) Author: Ned Deily (ned.deily) * (Python committer) Date: 2012-07-10 03:52
As usual, there seem to be small but significant differences among the implementations.  Testing with the three OS X Tk implementations shows that currently:
1. Aqua Tk 8.5 and Aqua Tk 8.4 do not supply a default extension
when saving.  With patch issue4832.diff applied, they still incorrectly do not supply a default extension. (Note, Aqua Tk's do not supply a file type filter in the Save File dialog box.)
2. X11 Tk 8.5 behaves like other Unix X11 Tk's: a default based on the selected File Type filter is used, i.e. .py for "Python files, .txt for "Text file".  Applying the patch does not change that correct behavior.

I tested a variation of Guilherme's patch which supplies a defaultextension of '.py' but only for OS X (rather than Windows).  With that patch (issue4832_rev2.patch):
1. Aqua Tk 8.5 now correctly supplies a default extension of '.py' on saves if the user does not enter an extension as part of the file name.
2. Aqua Tk 8.4 behavior is unchanged: it still incorrectly does not supply an extension if the user does not.  I don't see how to fix that but the use of Aqua Tk 8.4 is diminishing.
3. X11 Tk 8.5 behavior is unchanged: it still correctly supplies a default based on the selected File Type.

Since Aqua Tk 8.5 is the major Tk for OS X these days (it has been the system default since OS X 10.6) and the patch improves things for it, I'd like to see this go in.  I did test it on a Debian Linux X11.  It should behave the same on Windows as Roger's previous patch but it would be good to test it again.

As far as documentation changes, I don't see the need to have anything more than the usual IDLE/NEWS.txt file entry.
msg165199 - (view) Author: Roger Serwy (roger.serwy) * (Python committer) Date: 2012-07-10 19:36
I tried issue4832_rev2.patch on Ubuntu 11.04 with Tk 8.5 and it still behaves as Terry described.
msg165346 - (view) Author: Ned Deily (ned.deily) * (Python committer) Date: 2012-07-13 00:39
Terry, are you planning to commit this?  If not, I can do it. It would be good to get this into 3.3.0b2 since it does fix an important usability issue.
msg165347 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2012-07-13 01:19
I agree. Go ahead. But what do you think of applying to 2.7 and or 3.2?

I want to add a sentence to Idle help, which I want to edit for the tooltips issue also. But that is not a rush.
msg165371 - (view) Author: Roundup Robot (python-dev) (Python triager) Date: 2012-07-13 07:45
New changeset 677a9326b4d4 by Ned Deily in branch 'default':
Issue #4832: Modify IDLE to save files with .py extension by
msg165372 - (view) Author: Ned Deily (ned.deily) * (Python committer) Date: 2012-07-13 07:50
Committed for 3.3.  I'm +0.5 for 2.7 and 3.2.  It seems like a bug to me.  Terry, I'll leave it up to you to handle that and any further doc updates you want to make.
msg197461 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2013-09-10 18:40
With PEP 434, this can and I think should be backported. I should have done it for 2.7.5 and will try to do soon.
msg228638 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2014-10-06 04:30
Better late than never.  At least on Windows, with has defaultextension = '', changeing "Save as type" to "Text files" changes the default to ".txt".  I presume that this bonus feature is not available on OSX, where defaultextension = '.py'.  Before I update the doc (just before 2.7.9), can someone tell me what happens with linux, where defaultextension is '', as on Windows?
msg228651 - (view) Author: Saimadhav Heblikar (Saimadhav.Heblikar) * Date: 2014-10-06 10:05
I will try to describe the behavior on linux:

(Format used is "what i type in file name" -> "name which gets written to disk")

1. When files of type is: Python Files
   a -> -> -> -> (!) -> (!)

2. When files of type is: text file
    Same behavior as before, with .txt instead of .py/.pyw

3. When files of type is: All files
   a -> a -> -> -> ->

I hopefully have tried most of the combinations. If I have left out any, please let me know and I'll try them out.
msg228727 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2014-10-06 19:19
Thank you. It was in particular the switching between a -> and a -> a.txt that I described and wanted verified for linux.  The fact that names with extensions are left unchanged is important too.  I will have to think about how to describe this succinctly.
msg229133 - (view) Author: Terry J. Reedy (terry.reedy) * (Python committer) Date: 2014-10-12 09:39
Misdirected push message copied here.
New changeset 69cdf71bda12 by Terry Jan Reedy in branch '2.7':
Issue #3832: backport 677a9326b4d4 to 2.7 (and delete some obsolete code).
Date User Action Args
2022-04-11 14:56:43adminsetgithub: 49082
2020-06-08 00:29:28terry.reedyunlinkissue13504 dependencies
2020-06-06 16:01:46terry.reedylinkissue27965 superseder
2014-10-12 09:39:39terry.reedysetmessages: + msg229133
2014-10-06 19:19:54brian.curtinsetnosy: - brian.curtin
2014-10-06 19:19:10terry.reedysetmessages: + msg228727
2014-10-06 10:05:14Saimadhav.Heblikarsetmessages: + msg228651
2014-10-06 04:30:11terry.reedysetstatus: open -> closed

versions: + Python 2.7, - Python 3.3
nosy: + Saimadhav.Heblikar

messages: + msg228638
resolution: fixed
stage: commit review -> resolved
2014-02-04 12:02:59taleinatsetnosy: - taleinat
2013-09-10 18:40:47terry.reedysetmessages: + msg197461
2012-07-13 07:50:30ned.deilysetmessages: + msg165372
title: idle filename extension -> IDLE does not supply a default ext of .py on Windows or OS X for new file saves
2012-07-13 07:45:38python-devsetnosy: + python-dev
messages: + msg165371
2012-07-13 01:19:11terry.reedysetmessages: + msg165347
2012-07-13 00:39:06ned.deilysetmessages: + msg165346
2012-07-10 19:36:53roger.serwysetmessages: + msg165199
2012-07-10 03:52:36ned.deilysetfiles: + issue4832_rev2.patch

messages: + msg165154
2012-07-10 02:44:16roger.serwysetmessages: + msg165147
2012-07-09 23:29:18terry.reedysetnosy: + ned.deily
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assignee: terry.reedy
stage: patch review -> commit review
2012-07-09 21:48:36roger.serwylinkissue13504 dependencies
2012-07-09 21:48:25roger.serwysetfiles: + issue4832_rev1.patch

messages: + msg165128
stage: patch review
2011-12-14 18:49:55roger.serwysetfiles: + issue4832.diff
nosy: + roger.serwy
messages: + msg149466

2011-12-10 03:52:09terry.reedylinkissue10364 superseder
2011-03-09 02:23:07terry.reedysetnosy: terry.reedy, amaury.forgeotdarc, taleinat, ajaksu2, gpolo, geon, brian.curtin
messages: + msg130399
2011-03-09 02:16:22terry.reedysetnosy: + terry.reedy

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2010-07-20 20:31:43gpolosetmessages: + msg110966
2010-07-20 20:23:40brian.curtinsetnosy: + brian.curtin
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2010-07-20 20:13:29taleinatsetnosy: + taleinat
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2009-08-04 18:05:51gpolosetmessages: + msg91262
2009-08-04 17:47:49amaury.forgeotdarcsetmessages: + msg91260
2009-08-01 20:45:07gpolosetfiles: + fix_defaultextension.diff

messages: + msg91168
2009-05-13 19:46:43geonsetmessages: + msg87703
2009-05-13 19:07:02ajaksu2setmessages: + msg87702
2009-05-13 17:00:16amaury.forgeotdarcsetfiles: + defaultextension.patch

nosy: + amaury.forgeotdarc
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keywords: + patch
2009-04-26 22:17:11ajaksu2setpriority: normal
versions: - Python 2.6, Python 2.5, Python 3.0
nosy: + ajaksu2, gpolo

messages: + msg86620

type: behavior -> enhancement
2009-01-04 15:16:01geoncreate