Vim: allow left/right (h/l) motions to change lines + up/down (k/j) to move the cursor to the start/end

[asqarslanov]

Currently, when using Vim mode, the h (left) and l (right) keys behave exactly like in Vim: when activated at the beginning/end of a line, the cursor doesn’t wrap to the previous/next line. The same is true for the j (down) and k (up) motions: at the top/bottom line, when pressed, they are simply ignored instead of moving the cursor to the end/beginning of that line as in insert mode.

Some people may prefer when these motions don’t block the cursor and allow to jump over to different lines. It would nice if Zed had configuration options that allowed such behavior.

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Here is an illustration of what I’m trying to describe. Suppose, the cursor is |.

When I press h (left) at the beginning of a line, I want the cursor to wrap to the previous line:

1  The quick brown    ->    1  The quick brown|
2 |fox jumps over     ->    2  fox jumps over
3  the lazy dog       ->    3  the lazy dog

Or at the bottom line, when I press j (down):

1  The quick brown    ->    1  The quick brown
2  fox jumps over     ->    2  fox jumps over
3  the lazy| dog      ->    3  the lazy dog|

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In Vim, the left/right motions can be configured to change the line like this:

set whichwrap+=<,>,[,],h,l

(I didn’t find a way to enable the desired behavior for the up/down motions.)

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Zed may add configuration options similar to the following:

{
  "vim": {
    "boundary_movements": {
      // Disable (default)
      "left_right": "off",
      // Only enable for the left and right arrows
      "left_right": "arrows_only",
      // Only enable for `h` and `l`
      "left_right": "keys_only",
      // Enable for both `h`/`l` and the arrows
      "left_right": "on",

      // Disable (default)
      "up_down": "off",
      // Only enable for the up and down arrows
      "up_down": "arrows_only",
      // Only enable for `j` and `k`
      "up_down": "keys_only",
      // Enable for both `j`/`k` and the arrows
      "up_down": "on"
    }
  }
}

[asqarslanov]

Another note: in Helix, the cursor does wrap on left and right movements. In Zed’s Helix mode, this isn’t the case right now. Maybe, this should become enabled by default.

[asqarslanov]

I’ve tried to implement these changes myself in this PR: #25663.