chore(iterators): create Iterator module and migrate iterators to use it (#1392)

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

@@ -1,6 +1,7 @@
 local renderer = require "nvim-tree.renderer"
 local utils = require "nvim-tree.utils"
 local core = require "nvim-tree.core"
+local Iterator = require "nvim-tree.iterators.node-iterator"
 
 local M = {}
 
@@ -9,34 +10,29 @@ function M.fn(keep_buffers)
     return
   end
 
-  local buffer_paths = {}
-  for _, buffer in ipairs(vim.api.nvim_list_bufs()) do
-    table.insert(buffer_paths, vim.api.nvim_buf_get_name(buffer))
-  end
+  local buffer_paths = vim.tbl_map(function(buffer)
+    return vim.api.nvim_buf_get_name(buffer)
+  end, vim.api.nvim_list_bufs())
 
-  local function iter(nodes)
-    for _, node in pairs(nodes) do
-      if node.open then
-        local new_open = false
-
-        if keep_buffers == true then
-          for _, buffer_path in ipairs(buffer_paths) do
-            local matches = utils.str_find(buffer_path, node.absolute_path)
-            if matches then
-              new_open = true
-            end
+  Iterator.builder(core.get_explorer().nodes)
+    :hidden()
+    :applier(function(node)
+      node.open = false
+      if keep_buffers == true then
+        for _, buffer_path in ipairs(buffer_paths) do
+          local matches = utils.str_find(buffer_path, node.absolute_path)
+          if matches then
+            node.open = true
+            return
           end
         end
-
-        node.open = new_open
       end
-      if node.nodes then
-        iter(node.nodes)
-      end
-    end
-  end
+    end)
+    :recursor(function(n)
+      return n.nodes
+    end)
+    :iterate()
 
-  iter(core.get_explorer().nodes)
   renderer.draw()
 end