Bug: Skim shows nothing on Windows

[Grueslayer]

RTFM Checklist

• I have searched exisiting issues / discussions
• I have read the Wiki including the Advanced section
• I have read man fzf / I am well versed in shell fzf

Operating system

Windows

Shell

pwsh

Neovim version (nvim --version)

NVIM v0.13.0-dev-125+g9c5fba5df0

Fzf version (fzf --version)

sk 4.5.1

Output of :lua print(os.getenv('FZF_DEFAULT_OPTS'))

nil

Is the problem reproducible with mini.sh?

• My issue is reproducible with mini.sh
• My issue IS NOT reproducible with mini.sh
• I have not tested with mini.sh (not relevant, requires LSP, Windows, etc)

Fzf-lua configuration

require('fzf-lua').setup({
        fzf_bin = "sk",
        fzf_opts = {
          ['--layout'] = 'default',
        },
        winopts = {
          height = 0.95,
          width = 0.95
        },
})

Describe the bug / steps to reproduce

All actions (files, oldfiles, buffers etc.) show an empty list with no entries, the created command runs fine in console or executed in :term terminal, e.g. for files()

sk  --ansi --layout="default" --prompt="c:\Temp\\" --bind="alt-shift-down:preview-down,ctrl-e:end-of-line,ctrl-f:half-page-down,shift-down:preview-page-down,ctrl-u:unix-line-discard,ctrl-z:abort,alt-G:last,f4:toggle-preview,alt-g:first,f3:toggle-preview-wrap,alt-a:toggle-all,shift-up:preview-page-up,alt-shift-up:preview-up,ctrl-a:beginning-of-line,ctrl-b:half-page-up" --bind="alt-Q:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 1 nil {+} {q} {n}" --bind="alt-q:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 2 nil {+} {q} {n}" --bind="esc:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 6 nil {+} {q} {n}" --bind="ctrl-v:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 7 nil {+} {q} {n}" --bind="ctrl-s:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 3 nil {+} {q} {n}" --bind="ctrl-t:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 4 nil {+} {q} {n}" --bind="enter:execute-silent:^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 5 nil {+} {q} {n}" --bind="alt-f:accept(alt-f),alt-h:accept(alt-h),alt-i:accept(alt-i),ctrl-c:accept(ctrl-c)" --preview-window="nohidden:right:0" --multi --preview="^\"C:/Program Files/Neovim/bin/nvim.exe^\" -u NONE -l ^\"C:/Users/username /AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^\" 8 nil {} {q} {n}" --print-query --nth="-1.." --delimiter="[ ]" --height="100%" 

seems there is a STDIN/STDOUT problem or sk behaves different when not called inside a console and gives no output to neovim.

[phanen]

FzfLua files debug=v should show more useful info.
maybe related to FZF_DEFAULT_COMMAND

[Grueslayer]

Gives me nothing new

[Fzf-lua] FZF_DEFAULT_COMMAND: ^"C:/Program Files/Neovim/bin/nvim.exe^" -u NONE -l ^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/spawn.lua^" ^"return^ [==[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]==]^" || break
[Fzf-lua] fzf cmd: sk --print-query --prompt=^"C:\WINDOWS\system32\\^" --multi --bind=^"shift-down:preview-page-down,ctrl-u:unix-line-discard,ctrl-z:abort,alt-G:last,f4:toggle-preview,ctrl-a:beginning-of-line,alt-g:first,f3:toggle-preview-wrap,alt-a:toggle-all,ctrl-e:end-of-line,shift-up:preview-page-up,alt-shift-up:preview-up,ctrl-b:half-page-up,alt-shift-down:preview-down,ctrl-f:half-page-down^" --bind=^"alt-Q:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 1^ v^ {+}^ {q}^ {n}^" --bind=^"alt-q:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 2^ v^ {+}^ {q}^ {n}^" --bind=^"ctrl-v:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 3^ v^ {+}^ {q}^ {n}^" --bind=^"ctrl-t:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 5^ v^ {+}^ {q}^ {n}^" --bind=^"ctrl-s:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 4^ v^ {+}^ {q}^ {n}^" --bind=^"enter:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 6^ v^ {+}^ {q}^ {n}^" --bind=^"esc:execute-silent:^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 7^ v^ {+}^ {q}^ {n}^" --bind=^"alt-h:accept^(alt-h^),alt-i:accept^(alt-i^),ctrl-c:accept^(ctrl-c^),alt-f:accept^(alt-f^)^" --preview=^"^^\^"C:/Program Files/Neovim/bin/nvim.exe^^\^"^ -u^ NONE^ -l^ ^^\^"C:/Users/username/AppData/Local/nvim-data/lazy/fzf-lua/lua/fzf-lua/rpc.lua^^\^"^ 8^ v^ {}^ {q}^ {n}^" --nth=^"-1..^" --preview-window=^"nohidden:right:0^" --height=^"100^%^" --delimiter=^"[ ]^" --ansi --layout=^"default^" > ^"C:\Users\USERNAME\AppData\Local\Temp\nvim.0\wSVIfK\4^"

and command runs still fine when pasted to a console.

[phanen]

FZF_DEFAULT_COMMAND should be passed as env. Not sure why it don't work in fzf-lua when when in console.

Other idea:

• FzfLua files pipe_cmd=true, this should stream the cmd output to skim.
• or patch the source, skim also support --cmd

diff --git a/lua/fzf-lua/fzf.lua b/lua/fzf-lua/fzf.lua
index 6468ace..68db522 100644
--- a/lua/fzf-lua/fzf.lua
+++ b/lua/fzf-lua/fzf.lua
@@ -115,6 +115,10 @@ function M.raw_fzf(contents, fzf_cli_args, opts)
     end
     table.insert(shell_cmd, table.concat(cmd, " "))
   elseif utils.__IS_WINDOWS then
+    if opts.fzf_bin:find("^sk") then
+      cmd[#cmd + 1] = "--cmd"
+      cmd[#cmd + 1] = FZF_DEFAULT_COMMAND
+    end
     utils.tbl_join(shell_cmd, cmd)
   else
     table.insert(shell_cmd, table.concat(cmd, " "))

[phanen]

--cmd can override env
https://github.com/lotabout/skim/blob/e227cafda2031990ed180b3191a57bfc84980e5b/src/skim.rs#L145-L149

[phanen]

skim window support was added recently, skim-rs/skim#1010.
I'm not sure if skim can already work in fzf-lua on window.

[Grueslayer]

This shows list and can be filtered, but preview does not work and my defined formatter (path.filename_first) aren't applied.

* `FzfLua files pipe_cmd=true`, this should stream the cmd output to skim.

This doesn't, it opens the windows and immediatly close it, no :messages were written

* or patch the source, skim also support `--cmd`

[ibhagwan]

@Grueslayer, does it work if you disable all processing?

:FzfLua files fn_preprocess=false fn_postprocess=false fn_transform=false

Also try to run FzfLua profiles choose max-perf and run :FzfLua files fzf_bin=sk

Do any pickers work at all? How about just running :FzfLua<CR>?

[Grueslayer]

@ibhagwan

:FzfLua files fn_preprocess=false fn_postprocess=false fn_transform=false fzf_bin=sk

runs fine but without preview any only when all three are false.

max-perf also runs but without preview, An error are shown in the preview window

Der Befehl "\"C:/Program Files/Neovim/bin/nvim.exe^\"" ist entweder falsch geschrieben oder konnte nicht gefunden werden.   

which means comand not found in English.

First at all the path separator in Windows is backslash \ only some tools with un*x origin (like fzf.exe) accept forward slashes and convert them internally before direct filesystem access, as this is a default system error message, fzf-lua needs to give it in the right way.

Furthermore it looks like \ and ^ are used as escape char in a wrong way.

And no, also non file related pickers don't work at all.

[ibhagwan]

Furthermore it looks like \ and ^ are used as escape char in a wrong way.

That’s is the correct way to escape a literal with cmd.exe, that’s why it works with fzf, there are some quirks however and Fzf changed the escape theme for windows somewhere in v0.53 IIRC.

I believe the issue is different (or incorrect) escaping scheme for Windows used by skim when running commands, that’s why max-perf or fn_transform works as if uses the shell command directly with no escapes, fzf-lua needs to use " in its commands which need to be escaped with ^ which skim seems to have an issue with.

I can probably fix that from fzf-lua’s side by adjusting the escaping scheme when skim is used but I no longer have access to a Windows VM (which I used for Windows dev in the past).

[ibhagwan]

@phanen, FYI, there’s probably also a need to revisit the fzf Windows escaping theme, escaping nested quotes stopped working after v0.53 but since we started using base64 for the lua args we never get to nested quotes anymore.

The nested quotes escaping theme was wild… look at the tests for it, the wildest thing was that it actually worked even with _base64=false (which I used for troubleshooting windows issues):

fzf-lua/tests/libuv_spec.lua

Lines 46 to 60 in bd281b9

	it("shellescape (win caret)", function()
	eq(libuv.shellescape([[]], 2), [[^"^"]])
	eq(libuv.shellescape([["]], 2), [[^"\^"^"]])
	eq(libuv.shellescape([[^"]], 2), [[^"^^\^"^"]])
	eq(libuv.shellescape([[\"]], 2), [[^"\\\^"^"]])
	eq(libuv.shellescape([[\^"]], 2), [[^"^^\\\^"^"]])
	eq(libuv.shellescape([[^"^"]], 2), [[^"^^\^"^^\^"^"]])
	eq(libuv.shellescape([[__^^"^"__]], 2), [[^"__^^^^\^"^^\^"__^"]])
	eq(libuv.shellescape([[__!^^"^"__]], 2),
	-- 1st: ^"_^!^^^^\^"^^\^"_^"
	-- 2nd: ^"_^^^!^^^^^^^^^^\\\^"^^^^^^\\\^"_^"
	[[^"__^^^!^^^^^^^^^^\\\^"^^^^^^\\\^"__^"]])
	eq(libuv.shellescape([[__^^^^\^"^^\^"__]], 2),
	[[^"__^^^^^^^^^^\\\^"^^^^^^\\\^"__^"]])
	eq(libuv.shellescape([[^]], 2), [[^"^^^"]])

[Grueslayer]

Yes ^ is used for escaping in Windows cmd but \ is never used for escaping, let us assume we've a directory with spaces, that would be

ls -l test\ with\ space

in a un*x like context, where spaces are escaped by \.

In windows you have that argument surrounded by double quotes only:

dir "test with space"

But if you want to put a text with quotes as one argument, you have to use the ^ escape character

cmd /c "dir ^"test with space^""

The normal error message would be

Der Befehl "unknown.exe" ist entweder falsch geschrieben oder konnte nicht gefunden werden.

you see everything between the two quotes is what was executed, so skim tries to run

\"C:/Program Files/Neovim/bin/nvim.exe^\"

where the quotes are escaped by \ (which is wrong) and the backslash at the end is escaped by ^. I think the command line should be

"C:/Program Files/Neovim/bin/nvim.exe"

[ibhagwan]

The escaping scheme was a lot of trial and error with cmd.exe and the internal manipulations by fzf - that’s why it works with fzf but not with skim.

I’ll write up some commands soon which you can test in the command line (mainly nvim -l piped into skim) and we can reverse engineer which works, shouldn’t be that hard as we don’t need nested escapes - once we nail it down I’ll make the adjustments for skim on Windows.

[ibhagwan]

I spun a Windows VM, it seems that skim has an issue with double quotes within SKIM_DEFAULT_COMMAND haven't figured out yet if it's a bug or it expected a different escape mechanism, try this yourself with both fzf and skim:

The escaping scheme is most likely causing the preview issue as well as it cannot run the neovim headless callback, it also seems that it's escaping double quotes unix style, try this (in powershell) and see the differences:

$env:FZF_DEFAULT_COMMAND="fd --type f"; & fzf --preview="echo {}"
$env:FZF_DEFAULT_COMMAND="fd --type f"; & fzf --preview="echo ""{}"""
$env:SKIM_DEFAULT_COMMAND="fd --type f"; & sk --preview="echo {}"
$env:SKIM_DEFAULT_COMMAND="fd --type f"; & sk --preview="echo ""{}"""

Maybe @LoricAndre can shed some light on the internals of skim and escaping windows double quotes.

[LoricAndre]

I haven't advertised Windows yet because I was afraid of something like this 😅
I'll take a look, but yeah quotes in windows are a mess, even more so than in POSIX shells