Expand snippet on tabs. Add C++ snippets.

users/jrpotter/lang/cxx.nix

@@ -27,6 +27,11 @@ in
         },
       })
     '';
+
+    nvim-snippets = ''
+      require('luasnip').add_snippets('c', require('cxx.snippets'))
+      require('luasnip').add_snippets('cpp', require('cxx.snippets'))
+    '';
   };
 
   xdg.configFile."nvim/after/ftplugin/c.lua".text = ''

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

@@ -0,0 +1,57 @@
+local fmt = require('luasnip.extras.fmt').fmt
+local ls = require('luasnip')
+local ki = require('luasnip.nodes.key_indexer')
+local ul = require('utils.luasnip')
+
+local c = ls.choice_node
+local d = ls.dynamic_node
+local i = ls.insert_node
+local k = ki.new_key
+local r = ls.restore_node
+local s = ls.snippet
+local sn = ls.snippet_node
+local t = ls.text_node
+
+return {
+  s(
+    { name = 'for', trig = 'for' },
+    fmt([[
+for (<>; <>) {
+  <>
+}]],
+      {
+        c(1, {
+          sn(nil, {
+            i(1, 'int'),
+            t(' '),
+            i(2, 'i'),
+          }),
+          sn(nil, {
+            i(1, 'char *'),
+            i(2, 'c'),
+          }),
+        }),
+        d(2, function(_, parent)
+          local index = ul.choice_index(parent.nodes[2])
+          return sn(
+            nil,
+            r(1, string.format('for-%d', index), ({
+              sn(nil, {
+                i(1, 'i < N'),
+                t('; '),
+                i(2, '++i'),
+              }),
+              sn(nil, {
+                i(1, 'c'),
+                t('; '),
+                i(2, '++c'),
+              }),
+            })[index])
+          )
+        end, { 1 }),
+        ul.visual_isn(3),
+      },
+      { delimiters = '<>' }
+    )
+  ),
+}

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

@@ -38,11 +38,19 @@ function M.setup()
     },
     mapping = {
       ['<tab>'] = cmp.mapping(function(fallback)
-        if cmp.get_active_entry() then cmp.confirm() else fallback() end
+        if cmp.visible() then
+          cmp.confirm({ select = true })
+        else
+          fallback()
+        end
       end, { 'i', 's' }),
 
       ['<c-l>'] = cmp.mapping(function(fallback)
-        if cmp.visible() then cmp.abort() else fallback() end
+        if cmp.visible() then
+          cmp.abort()
+        else
+          fallback()
+        end
       end, { 'i', 's' }),
 
       ['<c-n>'] = cmp.mapping(function(fallback)

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

@@ -40,11 +40,12 @@ function M.setup()
       },
       [types.insertNode] = {
         passive = {
-          hl_group = 'DiagnosticHint',
+          hl_group = 'DiagnosticVirtualTextWarn',
         },
       },
       [types.choiceNode] = {
         active = {
+          hl_group = 'DiagnosticVirtualTextHint',
           virt_text = { { '⧨', 'DiagnosticHint' } },
         },
       },