feat(api): api.tree.find_file feature parity with open/toggle, convert all commands to API, document commands (#2039)

* fix(#1212): API find file feature parity

* fix(#2011): API find file feature parity

* fix(#2011): API find file feature parity

* fix(#2011): API find file feature parity

* fix(#2011): API find file feature parity

* fix(#2011): API find file feature parity

* fix(#2011): API find file feature parity

* fix(#2011): API find file feature parity

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

@@ -0,0 +1,51 @@
+local lib = require "nvim-tree.lib"
+local view = require "nvim-tree.view"
+local finders_find_file = require "nvim-tree.actions.finders.find-file"
+
+local M = {}
+
+---Open the tree, focusing if already open.
+---@param opts ApiTreeOpenOpts|nil|string legacy -> opts.path
+function M.fn(opts)
+  -- legacy arguments
+  if type(opts) == "string" then
+    opts = {
+      path = opts,
+    }
+  end
+  opts = opts or {}
+
+  local previous_buf = vim.api.nvim_get_current_buf()
+  local previous_path = vim.api.nvim_buf_get_name(previous_buf)
+
+  -- sanitise path
+  if type(opts.path) ~= "string" or vim.fn.isdirectory(opts.path) == 0 then
+    opts.path = nil
+  end
+
+  if view.is_visible() then
+    -- focus
+    lib.set_target_win()
+    view.focus()
+  else
+    -- open
+    lib.open { path = opts.path, current_window = opts.current_window }
+  end
+
+  -- find file
+  if M.config.update_focused_file.enable or opts.find_file then
+    -- update root
+    if opts.update_root then
+      require("nvim-tree").change_root(previous_path, previous_buf)
+    end
+
+    -- find
+    finders_find_file.fn(previous_path)
+  end
+end
+
+function M.setup(opts)
+  M.config = opts or {}
+end
+
+return M