g:fzf_preview_preview_key_bindings not working

[phongvcao]

Problems summary

g:fzf_preview_preview_key_bindings not working. The keybindings weren't helping me scrolling in the preview buffer of fzf-preview.vim. My same keybindings worked fine using original FZF's default preview mode.

Environment Information

• fzf-preview version (package.json): 0.4.9

• OS: macOS Catalina 10.15.5 19F101 x86_64

• Vim/Neovim version:

$ nvim --version
NVIM v0.4.3
Build type: Release
LuaJIT 2.0.5
Compilation: /usr/local/Homebrew/Library/Homebrew/shims/mac/super/clang -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1 -DNDEBUG -DMIN_LOG_LEVEL=3 -Wall -Wextra -pedantic -Wno-unused-parameter -Wstrict-prototypes -std=gnu99 -Wshadow -Wconversion -Wmissing-prototypes -Wimplicit-fallthrough -Wvla -fstack-protector-strong -fdiagnostics-color=auto -DINCLUDE_GENERATED_DECLARATIONS -D_GNU_SOURCE -DNVIM_MSGPACK_HAS_FLOAT32 -DNVIM_UNIBI_HAS_VAR_FROM -I/tmp/neovim-20191107-85913-1wbgqz6/neovim-0.4.3/build/config -I/tmp/neovim-20191107-85913-1wbgqz6/neovim-0.4.3/src -I/usr/local/include -I/tmp/neovim-20191107-85913-1wbgqz6/neovim-0.4.3/deps-build/include -I/usr/local/opt/gettext/include -I/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk/usr/include -I/tmp/neovim-20191107-85913-1wbgqz6/neovim-0.4.3/build/src/nvim/auto -I/tmp/neovim-20191107-85913-1wbgqz6/neovim-0.4.3/build/include
Compiled by brew@Catalina.local

Features: +acl +iconv +tui
See ":help feature-compile"

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "/usr/local/Cellar/neovim/0.4.3/share/nvim"

Run :checkhealth for more info

Provide a minimal init.vim

call plug#begin('~/.vim/plugged')
Plug 'junegunn/fzf'
Plug 'neoclide/coc.nvim', {'branch': 'release'}
Plug 'ryanoasis/vim-devicons'
call plug#end()

let g:coc_global_extensions = ['coc-fzf-preview']
let g:fzf_preview_preview_key_bindings = 'ctrl-k:preview-up,ctrl-j:preview-down,?:toggle-preview'

[yuki-yano]

It certainly doesn't seem to be working.
I've checked and it looks like it's going to take a little bit of work to fix, so could you please wait a bit?

[phongvcao]

yes I can wait.

[yuki-yano]

I was able to fix it sooner than expected.
Fixed: 0eba9be

Please check.

[phongvcao]

so when I set my vimrc like this:

call plug#begin('~/.vim/plugged')
Plug 'junegunn/fzf'
Plug 'neoclide/coc.nvim', {'branch': 'release'}
Plug 'ryanoasis/vim-devicons'
call plug#end()

let g:coc_global_extensions = ['coc-fzf-preview']
let g:fzf_preview_preview_key_bindings = 'ctrl-k:preview-up,ctrl-j:preview-down,?:toggle-preview'

then Ctrl-J works, but Ctrl-K doesn't work for some reasons (it does scroll up, but it only scrolls up for like 5-10 lines before the current line, not scrolling up for forever. In contrast, Ctrl-J can literally scroll down very far.

[phongvcao]

Ok so you can try my config, and then do this:

1. Open :CocCommand fzf-preview.Lines
2. Type some search term in the search prompt
3. Try scrolling down using <C-j> (should work - you can literally scroll down as far as you want)
4. Try scrolling up using <C-k> (you can only scroll up to a certain point - say 5-10 lines above the search-result line, but not more, where as original FZF can scroll up till first line of file).

The ability to scroll up till the first line is important, as most functions in my code are longer than 5-10 lines. Hence it would be great if the codes 20-30 lines above the searched result line can be seen.

To illustrate my point, this is what I did & how far I can scroll up (only 5-10 lines above the search result line and the scroll stops):

[yuki-yano]

The fzf preview cannot show the result of scrolling.
Therefore, grep results are displayed by cropping the file to show the matches first.

You can change grep's preview script to show the entire file, but it will start at the beginning of the file.

[phongvcao]

You can change grep's preview script to show the entire file, but it will start at the beginning of the file.

How exactly do I do this? Is there a way I can specify this via an option (e.g. g:fzf_preview_*?). Is it possible to have an option that center the matched result line in the preview screen, or let users customize how many lines above the matched result line?

[yuki-yano]

You can set it up with g:fzf_preview_grep_preview_cmd .
The default script is https://github.com/yuki-ycino/fzf-preview.vim/blob/master/bin/preview_fzf_grep

[phongvcao]

ok thanks Yuki I'll look into it.