cursor not placed properly with autoinsert when cycling completions

[stefanboca]

Make sure you have done the following

• Updated to the latest version of blink.cmp
• Searched for existing issues and documentation (try <C-k> on https://cmp.saghen.dev)

Bug Description

Say I type fori in lua. My completion menu looks like this:

I then select the next entry and the i disappears:

I then select the previous entry (the original) and the i is inserted, but the cursor is not moved, so the i is after the cursor:

I then accept the completion. The i remains inserted after the snippet:

auto_insert and preselect are enabled, as per default.

This might be a duplicate of #810, but I'm not sure.

-- Run with `nvim -u repro.lua`

vim.env.LAZY_STDPATH = '.repro'
load(vim.fn.system('curl -s https://raw.githubusercontent.com/folke/lazy.nvim/main/bootstrap.lua'))()

---@diagnostic disable-next-line: missing-fields
require('lazy.minit').repro({
  spec = {
    {
      'saghen/blink.cmp',
      build = 'cargo build --release',
      opts = {
        keymap = { preset = 'enter', cmdline = { preset = 'default' } },
      },
    },
    {
      'neovim/nvim-lspconfig',
      dependencies = {
        -- for installing lua_ls. for whatever reason this doesn't work the first time. so close and reopen `nvim -u repro.lua`
        -- or run :MasonInstall lua-language-server
        { 'williamboman/mason.nvim', opts = {} },
        { 'williamboman/mason-lspconfig.nvim', opts = { ensure_installed = {"lua_ls"} } },
      },
      opts = {
        servers = {
          lua_ls = {},
        },
      },
      config = function(_, opts)
        local lspconfig = require('lspconfig')
        for server, config in pairs(opts.servers) do
          -- passing config.capabilities to blink.cmp merges with the capabilities in your
          -- `opts[server].capabilities, if you've defined it
          config.capabilities = require('blink.cmp').get_lsp_capabilities()
          lspconfig[server].setup(config)
        end
      end,
    },
  },
})

Relevant configuration

keymap = { preset = "enter" }

neovim version

NVIM v0.11.0-dev+1493-g4d9405991 Build type: RelWithDebInfo LuaJIT 2.1.1720049189

blink.cmp version

main

[xzbdmw]

undo_preview inserts the extra i.

[xzbdmw]

Rather than the concept of undo, how about remembering the context (line content, etc) when the request was sent, so we can restore the content when selection is changed, and treat each new auto_insert stateless.

#810 can also be solved by this approach, the cause is that su is not cleared by undo_preview's logic, as list.preview_undo.text_edit is not updated when user keeps typing, only when selection is changed.