neovim: update completion bindings & add iferr snippet

neovim/.config/nvim/after/plugin/comp.lua

@@ -10,18 +10,18 @@ cmp.setup({
     end,
   },
   mapping = {
-    ["<C-j>"] = cmp.mapping(function()
+    ["<C-j>"] = cmp.mapping(function(fallback)
       if cmp.visible() then
         cmp.select_next_item({ behavior = cmp.SelectBehavior.Select })
       else
-        ls.jump(1)
+        fallback()
       end
     end),
-    ["<C-k>"] = cmp.mapping(function()
+    ["<C-k>"] = cmp.mapping(function(fallback)
       if cmp.visible() then
         cmp.select_prev_item({ behavior = cmp.SelectBehavior.Select })
       else
-        ls.jump(-1)
+        fallback()
       end
     end),
     ["<C-space>"] = cmp.mapping(function()
@@ -31,10 +31,27 @@ cmp.setup({
         cmp.complete()
       end
     end),
-    ["<TAB>"] = cmp.mapping.confirm({
-      select = true,
-      behavior = cmp.SelectBehavior.Insert,
-    }),
+    ["<TAB>"] = cmp.mapping(function(fallback)
+      if ls.jumpable(1) then
+        ls.jump(1)
+      else
+        if cmp.visible() then
+          cmp.confirm({
+            select = true,
+            behavior = cmp.SelectBehavior.Insert,
+          })
+        else
+          fallback()
+        end
+      end
+    end),
+    ["<S-TAB>"] = cmp.mapping(function(fallback)
+      if ls.jumpable(-1) then
+        ls.jump(-1)
+      else
+        fallback()
+      end
+    end),
     ["<C-S-j>"] = cmp.mapping.scroll_docs(4),
     ["<C-S-k>"] = cmp.mapping.scroll_docs(-4),
     ["<C-f>"] = cmp.mapping(function(fallback)
@@ -89,3 +106,88 @@ cmp.setup.filetype("gitcommit", {
 })
 
 require("luasnip.loaders.from_vscode").lazy_load()
+
+local s = ls.snippet
+local i = ls.insert_node
+local t = ls.text_node
+local d = ls.dynamic_node
+local sn = ls.snippet_node
+local fmt = require("luasnip.extras.fmt").fmt
+
+local ts_utils = require("nvim-treesitter.ts_utils")
+
+ls.add_snippets("go", {
+  s(
+    "iferr",
+    fmt(
+      [[
+    if err != nil {
+      return <>
+    }
+    ]],
+      {
+        d(1, function()
+          local current_node = ts_utils.get_node_at_cursor(0, true)
+          if not current_node then
+            return ""
+          end
+
+          local func = current_node
+          while func do
+            if func:type() == "function_declaration" then
+              break
+            end
+            func = func:parent()
+          end
+
+          if not func then
+            return ""
+          end
+
+          local return_type_node = func:child(3)
+          if not return_type_node then
+            return ""
+          end
+
+          local params = {}
+          for index = 0, return_type_node:child_count(), 1 do
+            local param = return_type_node:child(index)
+            if param then
+              if param:type() == "parameter_declaration" then
+                local text = ts_utils.get_node_text(param)
+                table.insert(params, text[1])
+              end
+            end
+          end
+
+          local rec = {
+            ["string"] = '""',
+            ["int"] = "0",
+            ["uint"] = "0",
+            ["error"] = "err",
+          }
+
+          local size = vim.tbl_count(params)
+          local x = {}
+          for index, param in ipairs(params) do
+            local replace = rec[param]
+            if replace ~= nil then
+              table.insert(x, i(index, replace))
+            else
+              table.insert(x, i(index, param))
+            end
+
+            if index < size then
+              table.insert(x, t(", "))
+            end
+          end
+
+          return sn(nil, x)
+        end, {}),
+      },
+      {
+        delimiters = "<>",
+      }
+    )
+  ),
+})