Fix: check if a plugin given as a requirement is a single-specificati…

…on table (#1041)

* Fix: check if a plugin given as a requirement is a single-specification table

* Update lua/packer.lua

Add @akinsho's edge case check for {{spec...}}

Co-authored-by: Akin <22454918+akinsho@users.noreply.github.com>

Co-authored-by: Akin <22454918+akinsho@users.noreply.github.com>

lua/packer.lua

@@ -268,7 +268,11 @@ manage = function(plugin_data)
   plugins[plugin_spec.short_name].url = util.remove_ending_git_url(plugin_spec.url)
 
   if plugin_spec.requires and config.ensure_dependencies then
-    if type(plugin_spec.requires) == 'string' then
+    -- Handle single plugins given as strings or single plugin specs given as tables
+    if
+      type(plugin_spec.requires) == 'string'
+      or (type(plugin_spec.requires) == 'table' and not vim.tbl_islist(plugin_spec.requires) and #plugin_spec.requires == 1)
+    then
       plugin_spec.requires = { plugin_spec.requires }
     end
     for _, req in ipairs(plugin_spec.requires) do