In the REPL window, redo works in mysterioius ways

[PEZ]

Issue Type: Bug

There is something funny with the undo/redo stack, such that if you undo things a few steps and then redo, resiprocity is lost: the things that are redone, are not those that were undone.

Steps to reproduce:

1. Close the REPL window.
2. Open the REPL window.
3. Type in some nice clojure code, and edit it some.
4. Undo
5. Redo

• Expected: The code should be restored to what it was before Undo.
• Actual: Depending on what you have typed and how you have edited it, different shapes of code materialises, but seldom the code that was there before Undo.

Further. If you press undo a few steps and then undo many steps, really crazy things can happen. Check this gif:

The last stuff that gets entered there is not me typing. I am just redoing several times.

Extension version: 2.0.60
VS Code version: Code 1.40.0 (86405ea23e3937316009fc27c9361deee66ffbf5, 2019-11-06T17:09:34.601Z)
OS version: Darwin x64 19.0.0

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz (12 x 2600)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: disabled_off protected_video_decode: unavailable_off rasterization: enabled skia_renderer: disabled_off surface_control: disabled_off surface_synchronization: enabled_on video_decode: enabled viz_display_compositor: enabled_on viz_hit_test_surface_layer: disabled_off webgl: enabled webgl2: enabled
Load (avg)	3, 3, 3
Memory (System)	16.00GB (0.08GB free)
Process Argv	-psn_0_458864
Screen Reader	no
VM	0%

[cfehse]

@PEZ @bpringe

This is what your sequence looks like on my systems (showing Windows but on Linux as well):

I cannot reproduce it. Peter if you have the time perhaps you can fire your Windows VM up and give it a try there? Brandon are you on macOS as well? Perhaps you can confirm the issue.

[PEZ]

I'll try it on Windows. Maybe it is my fix for lineendings that introduced this... That is easy enough to test.

[bpringe]

I'm on Windows. ctrl+z works for undo, but ctrl+y does not work for redo. Am I hitting the wrong keys? If not, redo does not work at all for me.

[bpringe]

Nevermind, I see that it's ctrl+shift+z to redo. But it's ctrl+y in the editor. Is there a reason not to make it the same in the repl window?

[bpringe]

Btw redo works fine for me on windows. I can't replicate what @PEZ showed.

[PEZ]

You are the second member of the Calva Team who ask about the ctrl+y mystery, @bpringe . Might be time we fix that. (In some good way.)

About the issue. I can't repro it on Windows. undo/redo works like a charm there.

It's interesting that it works on Linux. That might indicate that it is not an eol thing. Can someone of you debug what the eol setting the LineInputModel gets for the REPL prompt? I'd do it if it wasn't that it is painful, not only to use Windows, but also that it is so extremely slow in the virtual environment.

[PEZ]

On my Windows machine both ctrl+y and ctrl+shift+z are mapped to undo in the editor, btw.

[PEZ]

OK. I now tried this with Calva v2.0.50 (just to pick something older than my eol fix. It is the same. This could be some weird MacOS Catalina issue, because I think I should have noticed this before otherwise. (I newly upgraded to Cataline). Will check with my colleague tomorrow, who is still on El Capitain.