feat(open-file): Add new node selection action based on :drop command

doc/nvim-tree-lua.txt

@@ -1527,6 +1527,26 @@ node.open.edit()                              *nvim-tree-api.node.open.edit()*
     Folder: expand or collapse
     Root:   change directory up
 
+                                          *nvim-tree-api.node.open.tab_drop()*
+node.open.tab_drop()
+    Like edit(), but reuse already-opened window in tab. See also: |:drop| 
+    File:   open already-opened as per |nvim-tree.actions.open_file|
+    Folder: expand or collapse
+    Root:   change directory up
+    Usage example: >
+
+    require("nvim-tree").setup({
+        on_attach = function(bufnr)
+            local function opts(desc)
+                return { desc = 'nvim-tree: ' .. desc, buffer = bufnr, noremap = true, silent = true, nowait = true }
+            end
+            local ok, api = pcall(require, "nvim-tree.api")
+            assert(ok, "api module is not found")
+            vim.keymap.set("n", "<CR>", api.node.open.tab_drop, opts("Tab drop"))
+        end
+    })
+<
+
                                *nvim-tree-api.node.open.replace_tree_buffer()*
 node.open.replace_tree_buffer()
     |nvim-tree-api.node.edit()|, file will be opened in place: in the

lua/nvim-tree/actions/node/open-file.lua

@@ -141,13 +141,22 @@ local function pick_win_id()
   return win_map[resp]
 end
 
+
 local function open_file_in_tab(filename)
   if M.quit_on_open then
     view.close()
   end
   vim.cmd("tabe " .. vim.fn.fnameescape(filename))
 end
 
+-- See :drop command. This will always focus already-opened tab
+local function tab_drop(filename)
+  if M.quit_on_open then
+    view.close()
+  end
+  vim.cmd("tab :drop " .. vim.fn.fnameescape(filename))
+end
+
 local function on_preview(buf_loaded)
   if not buf_loaded then
     vim.bo.bufhidden = "delete"
@@ -284,6 +293,10 @@ function M.fn(mode, filename)
     return open_file_in_tab(filename)
   end
 
+  if mode == "tab_drop" then
+    return tab_drop(filename)
+  end
+
   if mode == "edit_in_place" then
     return edit_in_current_buf(filename)
   end

lua/nvim-tree/api.lua

@@ -162,6 +162,7 @@ local function open_preview(node)
 end
 
 Api.node.open.edit = wrap_node(open_or_expand_or_dir_up "edit")
+Api.node.open.tab_drop = wrap_node(open_or_expand_or_dir_up "tab_drop")
 Api.node.open.replace_tree_buffer = wrap_node(open_or_expand_or_dir_up "edit_in_place")
 Api.node.open.no_window_picker = wrap_node(open_or_expand_or_dir_up "edit_no_picker")
 Api.node.open.vertical = wrap_node(open_or_expand_or_dir_up "vsplit")