Use isn for visual selection indentations.

users/jrpotter/neovim/config/python/snippets.lua

@@ -47,7 +47,7 @@ for {} in {}:
             })[index])
           )
         end, { 1 }),
-        ul.visual_node,
+        ul.visual_dynamic_node(3),
       }
     )
   ),

users/jrpotter/neovim/config/utils/luasnip.lua

@@ -2,19 +2,17 @@ local M = {}
 
 local luasnip = require('luasnip')
 local types = require('luasnip.util.types')
-local function_node = require('luasnip').function_node
 
-M.visual_node = function_node(function(_, snip)
-  local env = snip.env
-  if type(env.LS_SELECT_RAW) ~= 'table' then
-    return env.LS_SELECT_RAW
-  end
-  local res = {}
-  for _, ele in ipairs(env.LS_SELECT_RAW) do
-    table.insert(res, ele)
-  end
-  return res
-end, {})
+function M.visual_dynamic_node(pos)
+  local f = luasnip.function_node
+  local isn = luasnip.indent_snippet_node
+
+  return isn(pos, {
+    f(function(_, parent)
+      return parent.snippet.env.LS_SELECT_DEDENT or {}
+    end)
+  }, '$PARENT_INDENT\t')
+end
 
 function M.choice_index(choice_node)
   for i, c in ipairs(choice_node.choices) do
@@ -46,6 +44,11 @@ function M.setup()
     },
   }
 
+  -- Track where we are expanding the snippet.
+  luasnip.env_namespace('INFO', {
+    init = function(info) return { POS = info.pos } end,
+  })
+
   vim.keymap.set({ 'i', 's' }, '<c-e>', function()
     if luasnip.choice_active() then
       return '<Plug>luasnip-next-choice'