[Snacks explorer] Moving files with unsaved changes

[fmorroni]

Moving a file that has unsaved changes using the snacks explorer just nukes the changes without even a warning. Is this a limitation or is there a way to configure it so that it will either

• ask to save before moving
• warn that unsaved changes are present and they'll be deleted

And is there a way to recover the lost changes after moving a file? (probably not but idk)

[drowning-cat]

Moving a file that has unsaved changes using the snacks explorer just nukes the changes without even a warning. Is this a limitation or is there a way to configure it so that it will either

Maybe the explorer_rename/explorer_move actions should simply rename buffers instead of creating new ones (see the patch). That would avoid cases like this.

Alternatively, it can simply be renamed to an empty string and assigned buftype=nofile to prevent any possible data loss.

Caution

Saving a renamed buffer prompts "Overwrite existing file <file>". To prevent this, :edit! | undo is used to sync the buffer after renaming.

Example patch (NO WARRANTY)

diff --git a/lua/snacks/explorer/actions.lua b/lua/snacks/explorer/actions.lua
index 410ff8d..8bafb8c 100644
--- a/lua/snacks/explorer/actions.lua
+++ b/lua/snacks/explorer/actions.lua
@@ -227,10 +227,12 @@ function M.actions.explorer_rename(picker, item)
   end
   Snacks.rename.rename_file({
     from = item.file,
-    on_rename = function(new, old)
-      Tree:refresh(vim.fs.dirname(old))
-      Tree:refresh(vim.fs.dirname(new))
-      M.update(picker, { target = new })
+    on_rename = function(new, old, ok)
+      if ok then
+        Tree:refresh(vim.fs.dirname(old))
+        Tree:refresh(vim.fs.dirname(new))
+        M.update(picker, { target = new })
+      end
     end,
   })
 end
@@ -249,7 +251,7 @@ function M.actions.explorer_move(picker)
   Snacks.picker.util.confirm("Move " .. what .. " to " .. t .. "?", function()
     for _, from in ipairs(paths) do
       local to = target .. "/" .. vim.fn.fnamemodify(from, ":t")
-      Snacks.rename.rename_file({ from = from, to = to })
+      Snacks.rename.rename_file({ from = from, to = to, force = true })
       Tree:refresh(vim.fs.dirname(from))
     end
     Tree:refresh(target)
diff --git a/lua/snacks/rename.lua b/lua/snacks/rename.lua
index 2e11ffd..605c2a7 100644
--- a/lua/snacks/rename.lua
+++ b/lua/snacks/rename.lua
@@ -8,7 +8,7 @@ M.meta = {
 -- Renames the provided file, or the current buffer's file.
 -- Prompt for the new filename if `to` is not provided.
 -- do the rename, and trigger LSP handlers
----@param opts? {from?: string, to?:string, on_rename?: fun(to:string, from:string, ok:boolean)}
+---@param opts? {from?: string, to?:string, force?:boolean, on_rename?: fun(to:string, from:string, ok:boolean)}
 function M.rename_file(opts)
   opts = opts or {}
   local from = vim.fn.fnamemodify(opts.from or opts.file or vim.api.nvim_buf_get_name(0), ":p")
@@ -18,6 +18,13 @@ function M.rename_file(opts)
 
   local function rename()
     assert(to, "to is required")
+    -- confirm override
+    if not opts.force and vim.uv.fs_stat(to) ~= nil then
+      local _, choice = pcall(vim.fn.confirm, ("Override '%s'?"):format(to), "&Yes\n&No\n&Cancel")
+      if choice ~= 1 then
+        return false
+      end
+    end
     M.on_rename_file(from, to, function()
       local ok = M._rename(from, to)
       if opts.on_rename then
@@ -66,19 +73,22 @@ function M._rename(from, to)
     Snacks.notify.error("Failed to rename file: `" .. from .. "`")
     return false
   end
-
-  -- replace buffer in all windows
+  -- rename the buffer
   local from_buf = vim.fn.bufnr(from)
-  if from_buf >= 0 then
-    local to_buf = vim.fn.bufadd(to)
-    vim.bo[to_buf].buflisted = true
-    for _, win in ipairs(vim.fn.win_findbuf(from_buf)) do
-      vim.api.nvim_win_call(win, function()
-        vim.cmd("buffer " .. to_buf)
-      end)
-    end
-    vim.api.nvim_buf_delete(from_buf, { force = true })
+  if not vim.api.nvim_buf_is_valid(from_buf) then
+    return false
+  end
+  local to_buf = vim.fn.bufnr(to)
+  if vim.api.nvim_buf_is_valid(to_buf) then
+    vim.api.nvim_buf_delete(to_buf, { force = true })
   end
+  vim.api.nvim_buf_set_name(from_buf, to)
+  -- HACK: sync the buffer to avoid the "Overwrite existing file?" prompt on save
+  vim.api.nvim_buf_call(from_buf, function()
+    local mod = vim.bo.modified
+    vim.cmd("edit! | undo")
+    vim.bo.modified = mod
+  end)
   return true
 end
 

And is there a way to recover the lost changes after moving a file? (probably not but idk)

@fmorroni

Preventive measures:

1. Use git.
2. Use filesystem snapshots. With btrfs, snapshots are lightweight enough to do backups frequently.

If the file is already gone:

1. Try recovering the data with grep:

   grep -a -b -B100 -A100 'local winmove = function(norm, float)' /dev/nvme0n1p6

2. Or use any other file recovery tool.

   Most filesystems do not erase deleted data immediately; they only mark it as free space. Until new data overwrites it, you may still be able to recover at least part of the file.

[fmorroni]

Hi awesome thanks! I'll check the patch when I have some time.

Regarding file recovery, I don't think git or snapshots would help in this case. If the file was never saved/persisted on disk it would also not be staged/commited in git nor saved in a system snapshot. Or am I missing something?

[drowning-cat]

Fair enough — no save, no backup.

[fmorroni]

Tested the patch, works great!

t doesn't actually save the file which was unexpected, but it still moves it while keeping the changes which is all I wanted.

Is there a way to put this in my config instead of changing the source code? I don't know when/if this will be added officially and I don't want to have to maintain local changes to the source.

And thanks again!

[drowning-cat]

Click me

-- lua/plugin/snacks_patch_move.lua

---@module 'snacks'

local Tree = require("snacks.explorer.tree")

vim.schedule(function()
  local M = require("snacks.rename")

  -- Renames the provided file, or the current buffer's file.
  -- Prompt for the new filename if `to` is not provided.
  -- do the rename, and trigger LSP handlers
  ---@param opts? {from?: string, to?:string, force?:boolean, on_rename?: fun(to:string, from:string, ok:boolean)}
  M.rename_file = function(opts)
    opts = opts or {}
    local from = vim.fn.fnamemodify(opts.from or opts.file or vim.api.nvim_buf_get_name(0), ":p")
    local to = opts.to and vim.fn.fnamemodify(opts.to, ":p") or nil
    from, to = svim.fs.normalize(from), to and svim.fs.normalize(to) or nil
    local function rename()
      assert(to, "to is required")
      -- confirm override
      if not opts.force and vim.uv.fs_stat(to) ~= nil then
        local _, choice = pcall(vim.fn.confirm, ("Override '%s'?"):format(to), "&Yes\n&No\n&Cancel")
        if choice ~= 1 then
          return false
        end
      end
      M.on_rename_file(from, to, function()
        local ok = M._rename(from, to)
        if opts.on_rename then
          opts.on_rename(to, from, ok)
        end
      end)
    end
    if to then
      return rename()
    end
    local root = svim.fs.normalize(vim.fn.getcwd(0))
    if from:find(root, 1, true) ~= 1 then
      -- file is outside cwd, use its parent dir as root
      root = vim.fs.dirname(from)
    end
    local extra = from:sub(#root + 2)
    vim.ui.input({
      prompt = "New File Name: ",
      default = extra,
      completion = "file",
    }, function(value)
      if not value or value == "" or value == extra then
        return
      end
      to = svim.fs.normalize(root .. "/" .. value)
      rename()
    end)
  end

  --- Rename a file and update buffers
  ---@param from string
  ---@param to string
  ---@return boolean ok
  function M._rename(from, to)
    from = vim.fn.fnamemodify(from, ":p")
    to = vim.fn.fnamemodify(to, ":p")
    vim.fn.mkdir(vim.fs.dirname(to), "p") -- ensure target directory exists
    -- rename the file
    local ret = vim.fn.rename(from, to)
    if ret ~= 0 then
      Snacks.notify.error("Failed to rename file: `" .. from .. "`")
      return false
    end
    -- rename the buffer preserving changes/history
    local from_buf = vim.fn.bufnr(from)
    if not vim.api.nvim_buf_is_valid(from_buf) then
      return false
    end
    local to_buf = vim.fn.bufnr(to)
    if vim.api.nvim_buf_is_valid(to_buf) then
      vim.api.nvim_buf_delete(to_buf, { force = true })
    end
    vim.api.nvim_buf_set_name(from_buf, to)
    -- HACK: Sync the buffer to avoid the "Overwrite existing file?" prompt on save
    vim.api.nvim_buf_call(from_buf, function()
      local mod = vim.bo.modified
      vim.cmd("edit! | undo")
      vim.bo.modified = mod
    end)
    return true
  end
end)

return {
  "folke/snacks.nvim",
  priority = 1000,
  lazy = false,
  ---@type snacks.Config
  opts = {
    picker = {
      sources = {
        explorer = {
          actions = {
            explorer_rename = function(picker, item)
              if not item then
                return
              end
              Snacks.rename.rename_file({
                from = item.file,
                on_rename = function(new, old, ok)
                  if ok then
                    Tree:refresh(vim.fs.dirname(old))
                    Tree:refresh(vim.fs.dirname(new))
                    picker:update({ target = new })
                  end
                end,
              })
            end,
            explorer_move = function(picker, item)
              ---@type string[]
              local paths = vim.tbl_map(Snacks.picker.util.path, picker:selected())
              if #paths == 0 then
                Snacks.notify.warn("No files selected to move. Renaming instead.")
                local explorer_rename = Snacks.picker.config.action(picker, "explorer_rename")
                return explorer_rename(picker, picker:current())
              end
              local target = picker:dir()
              local what = #paths == 1 and vim.fn.fnamemodify(paths[1], ":p:~:.") or #paths .. " files"
              local t = vim.fn.fnamemodify(target, ":p:~:.")
              Snacks.picker.util.confirm("Move " .. what .. " to " .. t .. "?", function()
                for _, from in ipairs(paths) do
                  local to = target .. "/" .. vim.fn.fnamemodify(from, ":t")
                  Snacks.rename.rename_file({ from = from, to = to, force = true })
                  Tree:refresh(vim.fs.dirname(from))
                end
                Tree:refresh(target)
                picker.list:set_selected() -- clear selection
                picker:update({ target = target })
              end)
            end,
          },
        },
      },
    },
  },
}

[fmorroni]

I'm only now trying out this config based patch and it also works great thanks!