`change-preview-window` should keep all other preview window configs unchanged

[bigH]

Checklist

• I have read through the manual page (man fzf)
• I have searched through the existing issues
• For bug reports, I have checked if the bug is reproducible in the latest version of fzf

Output of fzf --version

0.72.0

OS

• Linux
• macOS
• Windows
• Etc.

Shell

• bash
• zsh
• fish

Problem / Steps to reproduce

I would like any change-preview-window commands to keep any other preview configuration values unchanged. So, if I toggle wrapping on, resizing preview should retain the wrapping state.

printf 'item\n' |
fzf \
  --preview 'printf "%*s\n" 300 | tr " " x' \
  --preview-window 'right,40%,nowrap' \
  --bind 'ctrl-w:toggle-preview-wrap' \
  --bind 'ctrl-r:change-preview-window:80%'

Steps:

1. Run the command.
2. Press Ctrl-W to enable preview wrapping.
3. Press Ctrl-R to resize preview to 80%.
4. Press Ctrl-W again to show wrapped text in new preview size.

Expected: preview stays wrapped.

Actual: preview snaps back to startup nowrap.

[junegunn]

Fixed in b4a86a9.

Scope note: the fix only carries over wrap / wrapWord, not every preview-window field. change-preview-window is a declarative preset, not a diff. That's what makes cycling like right,40%|down,30%|hidden| work and what lets the empty trailing token reset to the original layout. Treating the current state as the baseline would break both.

wrap / wrapWord are different because they have their own toggle actions that are orthogonal to layout, so they're better modeled as session preferences than as part of the preset. Explicit wrap / nowrap in the spec still wins.

[bigH]

Thanks for fixing this so quick!

I see what you mean w/r/t how this is designed and works in practice.