refacto: split explorer module into multiple files

lua/nvim-tree/explorer/node-builders.lua

@@ -0,0 +1,86 @@
+local uv = vim.loop
+local utils = require'nvim-tree.utils'
+
+local M = {
+  is_windows = vim.fn.has('win32') == 1
+}
+
+local function get_dir_git_status(parent_ignored, status, absolute_path)
+  if parent_ignored then
+    return '!!'
+  end
+  local dir_status = status.dirs and status.dirs[absolute_path]
+  local file_status = status.files and status.files[absolute_path]
+  return dir_status or file_status
+end
+
+function M.folder(cwd, name, status, parent_ignored)
+  local absolute_path = utils.path_join({cwd, name})
+  local handle = uv.fs_scandir(absolute_path)
+  local has_children = handle and uv.fs_scandir_next(handle) ~= nil
+
+  return {
+    absolute_path = absolute_path,
+    git_status = get_dir_git_status(parent_ignored, status, absolute_path),
+    group_next = nil, -- If node is grouped, this points to the next child dir/link node
+    has_children = has_children,
+    name = name,
+    nodes = {},
+    open = false,
+  }
+end
+
+local function is_executable(absolute_path, ext)
+  if M.is_windows then
+    return utils.is_windows_exe(ext)
+  end
+  return uv.fs_access(absolute_path, 'X')
+end
+
+function M.file(cwd, name, status, parent_ignored)
+  local absolute_path = utils.path_join({cwd, name})
+  local ext = string.match(name, ".?[^.]+%.(.*)") or ""
+
+  return {
+    absolute_path = absolute_path,
+    executable = is_executable(absolute_path, ext),
+    extension = ext,
+    git_status = parent_ignored and '!!' or status.files and status.files[absolute_path],
+    name = name,
+  }
+end
+
+-- TODO-INFO: sometimes fs_realpath returns nil
+-- I expect this be a bug in glibc, because it fails to retrieve the path for some
+-- links (for instance libr2.so in /usr/lib) and thus even with a C program realpath fails
+-- when it has no real reason to. Maybe there is a reason, but errno is definitely wrong.
+-- So we need to check for link_to ~= nil when adding new links to the main tree
+function M.link(cwd, name, status, parent_ignored)
+  --- I dont know if this is needed, because in my understanding, there isnt hard links in windows, but just to be sure i changed it.
+  local absolute_path = utils.path_join({ cwd, name })
+  local link_to = uv.fs_realpath(absolute_path)
+  local stat = uv.fs_stat(absolute_path)
+  local open, nodes
+  if (link_to ~= nil) and uv.fs_stat(link_to).type == 'directory' then
+    open = false
+    nodes = {}
+  end
+
+  local last_modified = 0
+  if stat ~= nil then
+    last_modified = stat.mtime.sec
+  end
+
+  return {
+    absolute_path = absolute_path,
+    git_status = parent_ignored and '!!' or status.files and status.files[absolute_path],
+    group_next = nil,   -- If node is grouped, this points to the next child dir/link node
+    last_modified = last_modified,
+    link_to = link_to,
+    name = name,
+    nodes = nodes,
+    open = open,
+  }
+end
+
+return M