After buffer modification - in particular after deletion - adjacent
selection history entries may correspond to the same effective
selection when applied to the current buffer. This means that we
sometimes need to press <c-h> multiple times to make one visible
change. This is not what the user expects, so let's keep walking the
selection history until we hit an actual change.
Alternatively, we could minimize the selection history after buffer
changes but I think that would make the it worse after content
undo+redo.
Each selection undo operation is surrounded by pair of
begin_edition()/end_edition() calls.
The original reason for adding these was that in one of my preliminary
versions, a WinDisplay hook could break an undo chain, even if the
hook did not affect selections at all. This has since been fixed.
By surrounding the undo with begin_edition()/end_edition(), try to
ensure that any selection modification that happens in a WinDisplay
hook would not break the undo chain. Essentially this means that,
after using <c-h> to undo a buffer change, this was meant to
make sure that <c-k> could redo that buffer change.
However, it turns out this actually doesn't work. The attached test
case triggers an assertion. As described in the first paragraph,
the only real-world motivation for this is gone, so let's simplify
the behavior.
The assertion fix means that we can test the next commit better.
From the issue:
> It often happens to me that I carefully craft a selection with multiple
> cursors, ready to make changes elegantly, only to completely mess it
> up by pressing a wrong key (by merging the cursors for example). Being
> able to undo the last selection change (even if only until the previous
> buffer change) would make this much less painful.
Fix this by recording selection changes and allowing simple linear
undo/redo of selection changes.
The preliminary key bindings are <c-h> and <c-k>.
Here are some other vacant normal mode keys I considered
X Y
<backspace> <minus>
# ^ =
<plus> '
unfortunately none of them is super convenient to type. Maybe we
can kick out some other normal mode command?
---
This feature has some overlap with the jump list (<c-o>/<c-i>) and
with undo (u) but each of the three features have their moment.
Currently there's no special integration with either peer feature;
the three histories are completely independent. In future we might
want to synchronize them so we can implement Sublime Text's "Soft
undo" feature.
Note that it is possible to restore selections that predate a buffer
modification. Depending on the buffer modification, the selections
might look different of course. (When trying to apply an old buffer's
selection to the new buffer, Kakoune computes a diff of the buffers
and updates the selection accordingly. This works quite well for
many practical examples.)
This makes us record the full history of all selections for each
client. This seems wasteful, we could set a limit. I don't expect
excessive memory usage in practice (we also keep the full history of
buffer changes) but I could be wrong.
Closes#898
The next commit changes the selections to a history of
selections. Today we directly access the selections data member. Let's
instead use an accessor method, to reduce the number of changes in
the next commit.
This commit prevents `ga` from returning a “no last buffer” error
when the previously displayed buffer was removed.
Since the jumps list keeps track of the order in which buffers were
displayed already, handling arbitrary `delete-buffer`s as well,
cycle through it to implement `ga` instead of storing a pointer.
Note that this commit doesn't take into account buffer flags that
might exclude some buffers from being cycled over by commands.
Fixes#1840
set-face now takes a scope argument, and faces can be overridden on
a buffer or window basis.
colorscheme apply on global scope, which should be good enough for
now.
Fixes#1411
If a shell commands takes more than 1s to execute, a message will appear
on the status line notifying the user, along with the time Kakoune has
been waiting for.
