IDLE - pasting text doesn't delete selection

[weeble]

BPO	5124
Nosy	@terryjreedy, @ned-deily, @serwy, @bitdancer, @rovitotv, @serhiy-storchaka
Files	issue5124.patch idle_paste_replace.patch x11-paste.diff x11-paste-36.diff x11-paste-35.diff x11-paste-27.diff

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = 'https://github.com/terryjreedy'
closed_at = <Date 2016-06-11.23:42:59.539>
created_at = <Date 2009-02-01.18:52:13.458>
labels = ['expert-IDLE', 'type-feature']
title = "IDLE - pasting text doesn't delete selection"
updated_at = <Date 2016-06-12.04:37:15.907>
user = 'https://bugs.python.org/weeble'

bugs.python.org fields:

activity = <Date 2016-06-12.04:37:15.907>
actor = 'serhiy.storchaka'
assignee = 'terry.reedy'
closed = True
closed_date = <Date 2016-06-11.23:42:59.539>
closer = 'terry.reedy'
components = ['IDLE']
creation = <Date 2009-02-01.18:52:13.458>
creator = 'weeble'
dependencies = []
files = ['30385', '43195', '43303', '43323', '43324', '43325']
hgrepos = []
issue_num = 5124
keywords = ['patch']
message_count = 40.0
messages = ['80914', '80915', '91166', '190061', '190063', '190066', '190097', '190117', '190120', '190124', '190128', '192676', '267126', '267128', '267136', '267155', '267161', '267252', '267535', '267578', '267586', '267597', '267683', '267796', '267797', '268064', '268082', '268086', '268179', '268182', '268189', '268191', '268200', '268204', '268260', '268265', '268266', '268296', '268319', '268320']
nosy_count = 11.0
nosy_names = ['terry.reedy', 'gpolo', 'ned.deily', 'roger.serwy', 'weeble', 'r.david.murray', 'Todd.Rovito', 'Mark.Young', 'python-dev', 'serhiy.storchaka', 'Guilherme.Sim\xc3\xb5es']
pr_nums = []
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue5124'
versions = ['Python 2.7', 'Python 3.5', 'Python 3.6']

[weeble]

Steps to reproduce:

1. Start IDLE.
2. Enter some text:

spam
eggs

3. Select the first line ("spam") and press control+c to copy.
4. Select the second line ("eggs") and press control+v to paste.

Expected result:

spam
spam

(With the caret at the end of the second line and no selection.)

Actual result (IDLE 2.6, Tk/Tcl 8.4, Linux):

spam
eggsspam

(With "eggs" selected and the caret at the end of the second line.)

I don't think this happens to me on Windows. It might be deliberate; I
know that Tk has slightly different behaviour on Windows and Linux. But
it doesn't seem to be consistent with other behaviour: for example, if
instead of pasting I start typing, the selected text is erased and the
typed text replaces it.

I can look into this myself, but I would appreciate if someone else can
confirm that this is not the expected behaviour, since perhaps it is
only my Windows background that leads me to expect this.

[gpolo]

This is not really related to IDLE, it is how the Text widget behaves
under Linux, you will notice the same with tcl/tk 8.5.

Nevertheless, I would prefer to have the same results under Windows and
Linux.

[gpolo]

btw, I just added a patch for bpo-3559 which could be easily adjusted
to work as described in this issue.

[terryjreedy]

On Win7, I get the replacement behavior. I get the same in Notepad and Firefox, so this may be standard Windows behavior. What is standard in other linex and mac apps? If the tk difference is a standard platform difference, I might think we should leave it alone.

[rovitotv]

"What is standard in other linex and mac apps?"
-On Mac OS X 10.8.3 TextEdit I get the replacement behavior
-On Linux CentOS 6.4 gedit I get the replacement behavior
-On IDLE under the latest 3.4 pull I get the replacement behavior with Max OS X 10.8.3
-On IDLE under the latest 3.4 pull I get the eggsspam behavior with Linux CentOS 6.4 as Weeble described in the original bug report

So from my perspective Linux is behaving differently than Windows and Mac OS X.

[ned-deily]

X11-based Tk follows general X11 practice with regard to text pasting. See http://wiki.tcl.tk/3771 for some background. Old school X11 users expect pasting to work that way. This is yet another instance where Tk attempts to conform to the platform it is running on. I recommend closing this issue as X11 Tk (and, hence, IDLE) has behaved like this forever and changing it would be painful for many current X11 IDLE users.

[serwy]

There are many X11 applications that replace the selection with pasted text. GTK and Qt widgets behave that way. Here's a brief list: gedit (GTK), gummi (GTK), kate (Qt), texmaker (Qt).

Tkinter, for me, has become increasingly frustrating due to these subtle platform differences. (See bpo-14146, bpo-13582, and many more that deal with Tk on Mac.) For IDLE, I consider these behavior differences bugs.

The attached patch "fixes" this issue.

[GuilhermeSimes]

I think IDLE should ignore general X11 practice. I used Linux for years and have never seen this behavior before because almost all programs behave in the Mac/Windows way.

[ned-deily]

Unfortunately, there is no one right answer to paste behavior on X11, unlike on native Windows and Mac implementations where there is essentially system-wide consistent paste behavior enforced by the underlying operating system. As the Tk Wiki points out (and the comments hers concur), different users are going to have different expectations. If we want to make this behavior available with X11 Tk, then it really should be a user configurable option. Without providing an option, the overriding design principle is that the status quo wins a stalemate (http://www.boredomandlaziness.org/2011/02/status-quo-wins-stalemate.html).

[terryjreedy]

I agree that the paste replace should be added as an option on linux, but without a broader survey of Linux Idle users to convince me otherwise, I have to agree that the default should stay as it is. I do not see any call to make the x11 behavior an option on mac and windows.

[rovitotv]

I haver verified Roger's patch does indeed fix the problem on Linux CentOS 6.4 with IDLE 3.4.

The Linux situation is complex. Basically as I see it over the years pure X11 applications are becoming extinct and most developers either use GTK (for GNOME) or QT (for KDE). I don't blame anybody for moving to one of these toolkits because writing a pure X11 application is painful. In the near future Wayland http://en.wikipedia.org/wiki/Wayland_(display_server_protocol) will take over and I wonder how many X11 applications will actually be ported. I agree with Roger we should try and make IDLE as consistent as possible across operating systems.

+1 for applying the patch.