feat(#3132): add api.node.expand and api.node.collapse (#3133)

* feat: allow passing node to collapse all

* refactor: use snake case

* feat: handle api legacy calls and update signature

* refactor: make sure open is a boolean

* doc: collapse_all

* Revert "doc: collapse_all"

This reverts commit d243da3e14.

* add api.node.collapse

* add api.node.expand

* add api.node.expand

---------

Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/actions/tree/modifiers/collapse.lua

@@ -0,0 +1,81 @@
+local utils = require("nvim-tree.utils")
+local core = require("nvim-tree.core")
+local Iterator = require("nvim-tree.iterators.node-iterator")
+
+local FileNode = require("nvim-tree.node.file")
+local DirectoryNode = require("nvim-tree.node.directory")
+
+local M = {}
+
+---@return fun(path: string): boolean
+local function buf_match()
+  local buffer_paths = vim.tbl_map(function(buffer)
+    return vim.api.nvim_buf_get_name(buffer)
+  end, vim.api.nvim_list_bufs())
+
+  return function(path)
+    for _, buffer_path in ipairs(buffer_paths) do
+      local matches = utils.str_find(buffer_path, path)
+      if matches then
+        return true
+      end
+    end
+    return false
+  end
+end
+
+---Collapse a node, root if nil
+---@param node Node?
+---@param opts ApiCollapseOpts
+local function collapse(node, opts)
+  local explorer = core.get_explorer()
+  if not explorer then
+    return
+  end
+
+  node = node or explorer
+
+  local node_at_cursor = explorer:get_node_at_cursor()
+  if not node_at_cursor then
+    return
+  end
+
+  local matches = buf_match()
+
+  Iterator.builder({ node:is(FileNode) and node.parent or node:as(DirectoryNode) })
+    :hidden()
+    :applier(function(n)
+      local dir = n:as(DirectoryNode)
+      if dir then
+        dir.open = opts.keep_buffers == true and matches(dir.absolute_path)
+      end
+    end)
+    :recursor(function(n)
+      return n.group_next and { n.group_next } or n.nodes
+    end)
+    :iterate()
+
+  explorer.renderer:draw()
+  utils.focus_node_or_parent(node_at_cursor)
+end
+
+
+---@param opts ApiCollapseOpts|boolean|nil legacy -> opts.keep_buffers
+function M.all(opts)
+  -- legacy arguments
+  if type(opts) == "boolean" then
+    opts = {
+      keep_buffers = opts,
+    }
+  end
+
+  collapse(nil, opts or {})
+end
+
+---@param node Node
+---@param opts ApiCollapseOpts?
+function M.node(node, opts)
+  collapse(node, opts or {})
+end
+
+return M