LuaSnip source: extended filetypes are not honored

[SuzumiK]

Make sure you have done the following

• I have updated to the latest version of blink.cmp
• I have read the README

Bug Description

In LuaSnip, it is possible to extend snippets for file types with snippets from other file types, eg. ls.filetype_extend("python", { "all" }) to enable all snippets for python. Currently, the blink LuaSnip source does not pick up on these extensions because ls.get_snippets(ft) does not follow extensions. cmp_luasnip solves this by first fetching relevant snippet filetypes and then iterating over all of them: https://github.com/saadparwaiz1/cmp_luasnip/blob/98d9cb5c2c38532bd9bdb481067b20fea8f32e90/lua/cmp_luasnip/init.lua#L67

Relevant configuration

{
  'saghen/blink.cmp',
  version = 'v0.*', 
  dependencies = '{ L3MON4D3/LuaSnip', version = 'v2.*' },
  opts = {
    snippets = {
      expand = function(snippet) require('luasnip').lsp_expand(snippet) end,
      active = function(filter)
        if filter and filter.direction then
          return require('luasnip').jumpable(filter.direction)
        end
        return require('luasnip').in_snippet()
      end,
      jump = function(direction) require('luasnip').jump(direction) end,
    },
    sources = {
      completion = {
        enabled_providers = { 'lsp', 'path', 'luasnip', 'buffer' },
      },
    },
  }
}

neovim version

nightly

blink.cmp version: branch, tag, or commit

v0.7.6

[Saghen]

Ah, that would also remove the need for global_snippets if I'm not mistaken. Pr is welcome!