Open above and below are broken in multi-range selections

[dead10ck]

Summary

open_above and open_below are both broken on the secondary ranges of a multi-range selection. The secondary cursor ends up on a line above where it should be for both commands. e.g.,

[workspace]
resolver = "2"
members = [
  "#[|h]#elix-core",
  "#(|h)#elix-view",
  "#(|h)#elix-term",
  "helix-tui",
  "helix-lsp-types",
  "helix-lsp",
  "helix-event",
  "helix-dap",
  "helix-loader",
  "helix-vcs",
  "helix-parsec",
  "helix-stdx",
  "xtask",
]

Pressing o becomes:

[workspace]
resolver = "2"
members = [
  "helix-core",
  #[|]#
  "helix-view",#(|)#

  "helix-ter#(|m)#",

  "helix-tui",
  "helix-lsp-types",
  "helix-lsp",
  "helix-event",
  "helix-dap",
  "helix-loader",
  "helix-vcs",
  "helix-parsec",
  "helix-stdx",
  "xtask",
]

and pressing O becomes:

[workspace]
resolver = "2"
members = [
  #[|]#
  "helix-core",#(|)#

  "helix-vie#(|w)#",

  "helix-term",
  "helix-tui",
  "helix-lsp-types",
  "helix-lsp",
  "helix-event",
  "helix-dap",
  "helix-loader",
  "helix-vcs",
  "helix-parsec",
  "helix-stdx",
  "xtask",
]

From a bisect, it looks like the breakage happened in #12215

[RoloEdits]

I thought something seemed off, this was it. I can confirm this behavior too. Thought it was me doing wrong selections, and it ended up wonky because of that.

[TornaxO7]

Ooof, damn it, sorry.
I can investigate that (and add a test for the future xD).