fix: autocenter: avoid use of feedkeys

[emmanueltouzery]

I'm using the center feature, I was tracking down why I was unexpectedly getting some 'z' somewhere, then I realized that this feedkeys on focus was causing it. Calling through norm should achieve the same outcome but in a more controlled manner.

[emmanueltouzery]

To be clear it was a plugin changing window then asking for user input and the feedkeys inserted zz as if I had typed it in the input.

[alex-courtis]

zz is working on the branch.

I'm not able to reproduce the problem on master; can you please list replication steps. An nvt-min.lua would be great.

[emmanueltouzery]

ok, here is the min script:

vim.cmd [[set runtimepath=$VIMRUNTIME]]
vim.cmd [[set packpath=/tmp/nvt-min/site]]
local package_root = "/tmp/nvt-min/site/pack"
local install_path = package_root .. "/packer/start/packer.nvim"
local function load_plugins()
  require("packer").startup {
    {
      "wbthomason/packer.nvim",
      "nvim-tree/nvim-tree.lua",
      "nvim-tree/nvim-web-devicons",
      -- ADD PLUGINS THAT ARE _NECESSARY_ FOR REPRODUCING THE ISSUE
    },
    config = {
      package_root = package_root,
      compile_path = install_path .. "/plugin/packer_compiled.lua",
      display = { non_interactive = true },
    },
  }
end
if vim.fn.isdirectory(install_path) == 0 then
  print "Installing nvim-tree and dependencies."
  vim.fn.system { "git", "clone", "--depth=1", "https://github.com/wbthomason/packer.nvim", install_path }
end
load_plugins()
require("packer").sync()
vim.cmd [[autocmd User PackerComplete ++once echo "Ready!" | lua setup()]]
vim.opt.termguicolors = true
vim.opt.cursorline = true

-- MODIFY NVIM-TREE SETTINGS THAT ARE _NECESSARY_ FOR REPRODUCING THE ISSUE
_G.setup = function()
  require("nvim-tree").setup {
    view = {
      centralize_selection = true,
    }
  }
  vim.cmd("NvimTreeToggle")
end

function _G.repro()
  vim.cmd("wincmd l")
  vim.cmd("NvimTreeFocus")
  vim.fn.input("what say you?")
end

run it with nvim -nu repro.lua
let it launch, set up, then once nvim-tree is opened, run: :lua repro().

Without the fix, at the "What say you?" prompt, zz will be inserted.
With the fix, there'll be no zz.

That's the problem with feedkeys... it just.. feeds keys.. no matter the context, it'll do that. but there's no guarantee where these keys will be sent.

[alex-courtis]

Looks good. Reproduced failed and fixed case.

@kylo252 why did you choose feedkeys instead of a regular cmd? Is there an edge case we are not seeing?

[kylo252]

I don't recall exactly why I used feedkeys() but I know that vim.schedule() can be tricky!

hopefully it's enough to use nvim_buf_call()

[kylo252]

can you try this instead

  if opts.view.centralize_selection then
    create_nvim_tree_autocmd("BufEnter", {
      pattern = "NvimTree_*",
      callback = function()
        local bufnr = api.nvim_get_current_buf()
        vim.schedule(function()
          local keys = api.nvim_replace_termcodes("zz", true, false, true)
          api.nvim_buf_call(bufnr, function()
            api.nvim_feedkeys(keys, "n", true)
          end)
        end)
      end,
    })
  end

[emmanueltouzery]

but how would that be better than norm! zz? isn't the norm solution strictly simpler?

[kylo252]

@emmanueltouzery, what was missing from my implementation is ensuring that feedkeys() only fires in the specified buffer, so nvim_buf_call() should be called regardless.

I wasn't able to reproduce the issue, but using the feedkeys() vs vim.cmd could be debatable.

[emmanueltouzery]

ok, i'll try your solution asap, but most likely i won't manage today 👍

[alex-courtis]

Thanks @kylo252

[emmanueltouzery]

so I tried @kylo252 's solution and.. it didn't work for me.

this is the test startup file for @kylo252 's solution:

vim.cmd [[set runtimepath=$VIMRUNTIME]]
vim.cmd [[set packpath=/tmp/nvt-min/site]]
local package_root = "/tmp/nvt-min/site/pack"
local install_path = package_root .. "/packer/start/packer.nvim"
local function load_plugins()
  require("packer").startup {
    {
      "wbthomason/packer.nvim",
      {"emmanueltouzery/nvim-tree.lua", branch = 'zz_kylo'},
      "nvim-tree/nvim-web-devicons",
      -- ADD PLUGINS THAT ARE _NECESSARY_ FOR REPRODUCING THE ISSUE
    },
    config = {
      package_root = package_root,
      compile_path = install_path .. "/plugin/packer_compiled.lua",
      display = { non_interactive = true },
    },
  }
end
if vim.fn.isdirectory(install_path) == 0 then
  print "Installing nvim-tree and dependencies."
  vim.fn.system { "git", "clone", "--depth=1", "https://github.com/wbthomason/packer.nvim", install_path }
end
load_plugins()
require("packer").sync()
vim.cmd [[autocmd User PackerComplete ++once echo "Ready!" | lua setup()]]
vim.opt.termguicolors = true
vim.opt.cursorline = true

-- MODIFY NVIM-TREE SETTINGS THAT ARE _NECESSARY_ FOR REPRODUCING THE ISSUE
_G.setup = function()
  require("nvim-tree").setup {
    view = {
      centralize_selection = true,
    }
  }
  vim.cmd("NvimTreeToggle")
end

function _G.repro()
  vim.cmd("wincmd l")
  vim.cmd("NvimTreeFocus")
  vim.fn.input("what say you?")
end

and this is for my solution:

vim.cmd [[set runtimepath=$VIMRUNTIME]]
vim.cmd [[set packpath=/tmp/nvt-min/site]]
local package_root = "/tmp/nvt-min/site/pack"
local install_path = package_root .. "/packer/start/packer.nvim"
local function load_plugins()
  require("packer").startup {
    {
      "wbthomason/packer.nvim",
      {"emmanueltouzery/nvim-tree.lua", branch = 'no_feed_keys'},
      "nvim-tree/nvim-web-devicons",
      -- ADD PLUGINS THAT ARE _NECESSARY_ FOR REPRODUCING THE ISSUE
    },
    config = {
      package_root = package_root,
      compile_path = install_path .. "/plugin/packer_compiled.lua",
      display = { non_interactive = true },
    },
  }
end
if vim.fn.isdirectory(install_path) == 0 then
  print "Installing nvim-tree and dependencies."
  vim.fn.system { "git", "clone", "--depth=1", "https://github.com/wbthomason/packer.nvim", install_path }
end
load_plugins()
require("packer").sync()
vim.cmd [[autocmd User PackerComplete ++once echo "Ready!" | lua setup()]]
vim.opt.termguicolors = true
vim.opt.cursorline = true

-- MODIFY NVIM-TREE SETTINGS THAT ARE _NECESSARY_ FOR REPRODUCING THE ISSUE
_G.setup = function()
  require("nvim-tree").setup {
    view = {
      centralize_selection = true,
    }
  }
  vim.cmd("NvimTreeToggle")
end

function _G.repro()
  vim.cmd("wincmd l")
  vim.cmd("NvimTreeFocus")
  vim.fn.input("what say you?")
end

I'm not sure how to proceed, @kylo252, maybe you can test this and prepare a patch that fixes that issue? Note that this also fails in my real-world scenario, not only in this "artificial" reproduction.

[emmanueltouzery]

again. run the test files with nvim -nu filename.lua.

[emmanueltouzery]

And again, the instructions to reproduce are:

run it with nvim -nu repro.lua
let it launch, set up, then once nvim-tree is opened, run: :lua repro().

Without the fix, at the "What say you?" prompt, zz will be inserted.
With the fix, there'll be no zz.

[kylo252]

I guess I didn't account for the use of input() 😅

we can go with this version then

    callback = function()
      local bufnr = api.nvim_get_current_buf()
      vim.schedule(function()
        api.nvim_buf_call(bufnr, function()
          vim.cmd [[norm! zz]]
        end)
      end)
    end,

[emmanueltouzery]

yes, that works! force-pushed so that's now what the MR does.

btw it wasn't only a problem with input, in fact my original issue was with the "lightspeed" plugin, which waits for user input, and was "fed" that zz, therefore leading to unpredictable behavior.

[alex-courtis]

Tested OK with repro

[alex-courtis]

Thanks @emmanueltouzery @kylo252