Keybinding Enhancements

[blink1073]

Fixes #729
Fixes #1212
Fixes #2047
Fixes #2347

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Adds the following keybindings, including kill-ring support:

              'editor/start of line': "Meta+A",
              'editor/end of line': "Meta+E",
              'editor/previous line': "Meta+P",
              'editor/next line': "Meta+N",
              'editor/previous char': "Meta+B",
              'editor/next char': "Meta+F",
              'editor/previous word': "Meta+Left",
              'editor/next word': "Meta+Right",
              'editor/kill to line end': "Meta+K",
              'editor/kill to line start': "Meta+U",
              'editor/yank': 'Meta+Y',
              'editor/rotate kill ring': 'Shift+Meta+Y',
              'editor/kill previous word': 'Meta+Backspace',
              'editor/kill next word': 'Meta+D',
              'editor/start of document': 'Ctrl+Up',
              'editor/end of document': 'Ctrl+Down',

Also makes the follow existing key sequences configurable:

              'editor/undo': 'Ctrl+U',
              'editor/redo': 'Ctrl+Y',
              'editor/cut': 'Ctrl+X',
              'editor/copy': 'Ctrl+C',
              'editor/paste': 'Ctrl+V',
              'editor/delete': 'Del',
              'editor/select All': "Ctrl+A",
              'editor/save as': 'Ctrl+Shift+S',

The only changed shortcut is

              'editor/save all': 'Ctrl+Alt+S',

[blink1073]

I've completed what I originally intended, but am open to suggestion. We could also add another Key column in leiu of the user input method. However, either way we'd have to keep track of state to tell the difference between C-x and C-xa.

[Nodd]

User input method seems more natural to me. If I remember well Qt supports multiple letter key out of the box so it would be easy to add afterwards.

[goanpeca]

@blink1073 what needs to be done to get this going?

[blink1073]

@goanpeca, this PR is ready as far as I'm concerned. I think it demonstrates a basic functionality that we are missing. I'm not terribly excited about implementing the multi-keystroke functionality.

[goanpeca]

Why (the multi keystroke), sorry I am kinda o ignorant on this emacs issue...

By multi keystroke it means entering in different states where different keystrokes are used? or..?

[blink1073]

Right, unless there is a built in way for Qt to sense a Keystroke sequence for us.

[blink1073]

Also, there is the UI of how the user sets the preference for a complex Keystroke sequence. We could allow them to type it in a box with validation, or enter it as a raw key sequence (which for example KDE does when you enter system keyboard shortcuts).

[goanpeca]

I do not know if Qt has a default for handling states.. if it does not, well I guess is something we need to handle... which, unless I am missing something, would not be very complicated.

[Nodd]

From http://doc.qt.io/qt-5/qkeysequence.html:

GNU Emacs Style Key Sequences

Key sequences similar to those used in GNU Emacs, allowing up to four key codes, can be created by using the multiple argument constructor, or by passing a human-readable string of comma-separated key sequences.

For example, the key sequence, Ctrl X followed by Ctrl C, can be specified using either of the following ways:

QKeySequence(tr("Ctrl+X, Ctrl+C"));
QKeySequence(Qt::CTRL + Qt::Key_X, Qt::CTRL + Qt::Key_C);

[goanpeca]

@Nodd I do not see how this would solve this issue of having states?

[Nodd]

Why do you mean by "state" ?
Why I showed is exactly what is needed to implement:

Add handling of keyboard shortcuts with multiple letter keys? (e.g. C-xs for save).

Qt supports them out of the box.

[goanpeca]

@Nodd, yes now I see how to use it, my bad ;-)

[ccordoba12]

Sorry for not reviewing this one before. I'll merge first the other PRs from @goanpeca that are almost ready, and then I'll continue with this one :-)

[goanpeca]

Almost :-| ? ? ?

[blink1073]

I created a small demo showing how to get keyboard sequences from the user. This could be used as the basis for the Keyboard Preferences dialog.

[blink1073]

https://gist.github.com/blink1073/946df268c3685a3f443e

[ccordoba12]

What does Kill mean? Could you find a better word? ;-)

Also, I'd like (when possible) to use here the same shortcuts as the IPython console (just for consistency and muscle memory :-)

You can find them in

Help > IPython doc > Console help

[blink1073]

Ahem: "C-k: kill from cursor to the end of the line", from the exact docs you pointed to 😛

[ccordoba12]

I know ;-) But since these shortcuts are also going yo be used by people not familiar with Emacs, I was thinking to use Delete or Clear instead of Kill

[ccordoba12]

This is good and simple, I like it!

The only thing is that I'd like to add more shortcuts because (most surely) people will expect them as part of offering Emacs keybindings. Some of them could be

• C-x-s -> Save
• C-x-f -> Open
• C-s -> Open search and repeat search
• M-> -> Go to file end
• M-< -> Go to file start

I don't if @blink1073 can think of others :-)

[blink1073]

@ccordoba12, we cannot use compound keyboard preferences unless we change the way they are entered in the dialog.

[goanpeca]

@blink1073 you would prefer an extra column? or a redesign (with no columns) and a dynamic entry of shortcuts?

[Nodd]

The columns work, but are not very user-friendly. Adding more of them will be even worse. I'd say that the right thing to do is to enter shortcuts dynamically, it's more practical and more modern.

Here is another idea for later: define default presets to be loaded by the user (Spyder default, Emacs, Matlab, R, Sublime Text, Vi...)

[blink1073]

@ccordoba12, I don't follow. You want me to redo the rebase? I'd just as soon copy these files and start a new PR to be honest with you.

[ccordoba12]

That'd be fine too :-) I just thought you could strip half of your commits here to fix things, but my git-fu is very limited to be honest ;-)

[blink1073]

Squashing to one commit did the trick, ready!

[ccordoba12]

Great!! I hope it's not too much to ask, but could you amend the commit message to write something simpler on it? :-)

[blink1073]

Done!

[ccordoba12]

Thanks! I think the only thing left to fix Meta+Less and Meta+Greater :-)

[blink1073]

What do you suggest? The system defaults still work: Ctrl+Home and Ctrl+End.

[blink1073]

Should we just use those and punt?

[ccordoba12]

Yes, let's do that for now. Then in the (future) PR that implements Emacs keybindings, you can see how to solve the issue with Meta+{<,>} :-)

[blink1073]

All set.

[ccordoba12]

Unfortunately all shortcuts that involve Meta don't work on PyQt5. I don't know why :-)

[ccordoba12]

@Nodd, could you test this branch in PyQt5 5.4 to see if in that version this problem is fixed?

[Nodd]

Nope, Meta doesn't work on PyQt5.4.1 either.

[blink1073]

Perhaps the Meta key has moved to something like the Esc key in PyQt5?

[Nodd]

I don't think so since in #2367 I can set a shortcut using Meta (but I can't use it). Or only the internal representation, not the translated one ?
If it has changed, maybe it's Super now.

[blink1073]

Everything is working on PyQt5 on my Mac.

[blink1073]

[Python 3.4.3 64bits, Qt 5.3.1, PyQt5 5.3.2 on Darwin]

[ccordoba12]

Please update this value to 18.1.0. I merged PR #2237 with the wrong CONF_VERSION and now we need this value :-)

[ccordoba12]

@blink1073, it seems the problem is only on Linux then ;-)

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I think we should merge this PR as it is now and try to find suitable shortcuts in another PR or in master (I could do that :-). This would let us keep things moving because there's nothing else to do here (except for my last comment :-)

@blink1073, what do you think?

[blink1073]

Done, merge away!

[ccordoba12]

Ok, merging!!