feat(filesystem): Implement shared clipboard

Author: miroshQa

README.md

@@ -45,6 +45,7 @@ should you!
   plenty of room to display the whole tree.
 - Neo-tree does not need to be manually refreshed (set `use_libuv_file_watcher=true`)
 - Neo-tree can intelligently follow the current file (set `follow_current_file.enabled=true`)
+- Neo-tree can copy and cut files over many neovim instances (est `filesystem.shared_clipboard=true`)
 - Neo-tree is thoughtful about maintaining or setting focus on the right node
 - Neo-tree windows in different tabs are completely separate
 - `respect_gitignore` actually works!

lua/neo-tree/defaults.lua

@@ -453,6 +453,7 @@ local config = {
     async_directory_scan = "auto", -- "auto"   means refreshes are async, but it's synchronous when called from the Neotree commands.
                                    -- "always" means directory scans are always async.
                                    -- "never"  means directory scans are never async.
+    shared_clipboard = false,      -- Enabling this feature allows you to copy and cut files over different instances of neovim
     scan_mode = "shallow", -- "shallow": Don't scan into directories to detect possible empty directory a priori
                            -- "deep": Scan into directories to detect empty or grouped empty directories a priori.
     bind_to_cwd = true, -- true creates a 2-way binding between vim's cwd and neo-tree's root

lua/neo-tree/sources/filesystem/commands.lua

@@ -6,6 +6,7 @@ local utils = require("neo-tree.utils")
 local filter = require("neo-tree.sources.filesystem.lib.filter")
 local renderer = require("neo-tree.ui.renderer")
 local log = require("neo-tree.log")
+local shared_clipboard = require("neo-tree.sources.filesystem.lib.shared_clipboard")
 
 local M = {}
 local refresh = function(state)
@@ -16,6 +17,12 @@ local redraw = function(state)
   renderer.redraw(state)
 end
 
+local sync_with_shared_clipboard = function(state)
+  if state.shared_clipboard then
+    shared_clipboard.save_clipboard(state.clipboard)
+  end
+end
+
 M.add = function(state)
   cc.add(state, utils.wrap(fs.show_new_children, state))
 end
@@ -35,19 +42,23 @@ end
 ---Marks node as copied, so that it can be pasted somewhere else.
 M.copy_to_clipboard = function(state)
   cc.copy_to_clipboard(state, utils.wrap(redraw, state))
+  sync_with_shared_clipboard(state)
 end
 
 M.copy_to_clipboard_visual = function(state, selected_nodes)
   cc.copy_to_clipboard_visual(state, selected_nodes, utils.wrap(redraw, state))
+  sync_with_shared_clipboard(state)
 end
 
 ---Marks node as cut, so that it can be pasted (moved) somewhere else.
 M.cut_to_clipboard = function(state)
   cc.cut_to_clipboard(state, utils.wrap(redraw, state))
+  sync_with_shared_clipboard(state)
 end
 
 M.cut_to_clipboard_visual = function(state, selected_nodes)
   cc.cut_to_clipboard_visual(state, selected_nodes, utils.wrap(redraw, state))
+  sync_with_shared_clipboard(state)
 end
 
 M.move = function(state)
@@ -57,6 +68,7 @@ end
 ---Pastes all items from the clipboard to the current directory.
 M.paste_from_clipboard = function(state)
   cc.paste_from_clipboard(state, utils.wrap(fs.show_new_children, state))
+  sync_with_shared_clipboard(state)
 end
 
 M.delete = function(state)

lua/neo-tree/sources/filesystem/init.lua

@@ -383,6 +383,10 @@ M.setup = function(config, global_config)
       end,
     })
   end
+
+  if config.shared_clipboard then
+    require("neo-tree.sources.filesystem.lib.shared_clipboard").init()
+  end
 end
 
 ---Expands or collapses the current node.

lua/neo-tree/sources/filesystem/lib/shared_clipboard.lua

@@ -0,0 +1,92 @@
+local fs_watch = require("neo-tree.sources.filesystem.lib.fs_watch")
+local manager = require("neo-tree.sources.manager")
+local events = require("neo-tree.events")
+local renderer = require("neo-tree.ui.renderer")
+
+local M = {}
+
+local clipboard_state_dir_path = vim.fn.stdpath("state") .. "/neo-tree/"
+local clipboard_file_path = clipboard_state_dir_path .. "filesystem-clipboard.json"
+local clipboard_file_last_mtime = nil
+
+
+M.save_clipboard = function(clipboard)
+  local file = io.open(clipboard_file_path, "w+")
+  -- We want to erase data in the file if clipboard is nil instead writing null
+  if not clipboard or not file then
+    return
+  end
+
+  file:write(vim.json.encode(clipboard))
+  file:flush()
+  clipboard_file_last_mtime = vim.uv.fs_stat(clipboard_file_path).mtime
+end
+
+M._load_clipboard = function()
+  local file = io.open(clipboard_file_path, "r")
+  if not file then
+    return nil
+  end
+  local content = file:read("*a")
+  local is_success, clipboard = pcall(vim.json.decode, content)
+  if not is_success then
+    return nil
+  end
+  return clipboard
+end
+
+M._update_cilpboard = function()
+  if not vim.fn.filereadable(clipboard_file_path) then
+    return
+  end
+  local cur_mtime = vim.uv.fs_stat(clipboard_file_path).mtime
+  if
+    not clipboard_file_last_mtime
+    -- We need exactly >= because it allows us to synchronize the clipboard
+    -- even with trees openned in another window (in the current Neovim instance)
+    or M._is_left_mtime_greater_or_equal(cur_mtime, clipboard_file_last_mtime)
+  then
+    local clipboard = M._load_clipboard()
+    manager._for_each_state("filesystem", function(state)
+      state.clipboard = clipboard
+      vim.schedule(function()
+        renderer.redraw(state)
+      end)
+    end)
+    clipboard_file_last_mtime = cur_mtime
+  end
+end
+
+M._is_left_mtime_greater_or_equal = function(a, b)
+  if a.sec > b.sec then
+    return true
+  elseif a.sec == b.sec and a.nsec >= b.nsec then
+    return true
+  end
+  return false
+end
+
+M.init = function()
+  if vim.fn.isdirectory(clipboard_state_dir_path) == 0 then
+    vim.fn.mkdir(clipboard_state_dir_path)
+  end
+
+  events.subscribe({
+    event = events.STATE_CREATED,
+    handler = function(state)
+      if state.name ~= "filesystem" then
+        return
+      end
+      vim.schedule(function()
+        M._update_cilpboard()
+      end)
+    end,
+  })
+
+  -- Using watch_folder because we haven't "watch_file" :)
+  fs_watch.watch_folder(clipboard_state_dir_path, function()
+    M._update_cilpboard()
+  end, true)
+end
+
+return M