From 7339958a08b87493d4820562a83f380d142f32b2 Mon Sep 17 00:00:00 2001
From: tastytea <tastytea@tastytea.de>
Date: Fri, 12 Aug 2022 19:19:20 +0200
Subject: [PATCH] nvim: cmp: dwim tab

---
 .config/nvim/lua/my/completion.lua | 30 +++++++++++++++++++++++++-----
 1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/.config/nvim/lua/my/completion.lua b/.config/nvim/lua/my/completion.lua
index 7a304ae..ea7455c 100644
--- a/.config/nvim/lua/my/completion.lua
+++ b/.config/nvim/lua/my/completion.lua
@@ -17,13 +17,14 @@ packer.use {
     },
     config = function()
         local cmp = require'cmp'
-        if cmp == nil then
-            return
-        end
+        if not cmp then return end
+        local luasnip = require('luasnip')
+        if not luasnip then return end
+
         cmp.setup({
             snippet = {
                 expand = function(args)
-                    require('luasnip').lsp_expand(args.body)
+                    luasnip.lsp_expand(args.body)
                 end,
             },
             window = {
@@ -37,7 +38,26 @@ packer.use {
                 ['<C-e>'] = cmp.mapping.abort(),
                 ['<End>'] = cmp.mapping.abort(),
                 ['<CR>'] = cmp.mapping.confirm({ select = false }),
-                ['<tab>'] = cmp.mapping.confirm({ select = true }),
+                ['<Tab>'] = cmp.mapping(function(fallback)
+                    if cmp.visible() then
+                        cmp.select_next_item()
+                    elseif luasnip.expandable() then
+                        luasnip.expand()
+                    elseif luasnip.expand_or_jumpable() then
+                        luasnip.expand_or_jump()
+                    else
+                        fallback()
+                    end
+                end),
+                ['<S-Tab>'] = cmp.mapping(function(fallback)
+                    if cmp.visible() then
+                        cmp.select_prev_item()
+                    elseif luasnip.jumpable(-1) then
+                        luasnip.kump(-1)
+                    else
+                        fallback()
+                    end
+                end)
             }),
             sources = cmp.config.sources({
                 { name = 'nvim_lsp' },