From 659ef00c71fd17efd2d8ffe5bbe5bd9f1698e73d Mon Sep 17 00:00:00 2001
From: Brian Picciano <me@mediocregopher.com>
Date: Sun, 6 Oct 2024 17:43:18 +0200
Subject: Drag my neovim config kicking and screaming into the future (LSP)

---
 nvim/init.lua | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)
 create mode 100644 nvim/init.lua

(limited to 'nvim/init.lua')

diff --git a/nvim/init.lua b/nvim/init.lua
new file mode 100644
index 0000000..9f4e393
--- /dev/null
+++ b/nvim/init.lua
@@ -0,0 +1,91 @@
+--------------------------------------------------------------------------------
+-- LSP configuration. nvim-cmp related stuff taken from:
+-- https://github.com/neovim/nvim-lspconfig/wiki/Autocompletion/217feffc675a17d8ab95259ed9d4c6d62e1cd2e1
+--------------------------------------------------------------------------------
+
+local lspconfig = require("lspconfig")
+
+local capabilities = require("cmp_nvim_lsp").default_capabilities()
+
+-- https://github.com/hrsh7th/nvim-cmp/issues/373#issuecomment-1434284568
+capabilities.textDocument.completion.completionItem.snippetSupport = false
+
+lspconfig.gopls.setup {
+    capabilities = capabilities,
+}
+
+local cmp = require("cmp")
+cmp.setup {
+  mapping = cmp.mapping.preset.insert({
+    ['<C-u>'] = cmp.mapping.scroll_docs(-4), -- Up
+    ['<C-d>'] = cmp.mapping.scroll_docs(4), -- Down
+    -- C-b (back) C-f (forward) for snippet placeholder navigation.
+    ['<C-Space>'] = cmp.mapping.complete(),
+    ['<CR>'] = cmp.mapping.confirm {
+      behavior = cmp.ConfirmBehavior.Replace,
+      select = true,
+    },
+    ['<Tab>'] = cmp.mapping(function(fallback)
+      if cmp.visible() then
+        cmp.select_next_item()
+      else
+        fallback()
+      end
+    end, { 'i', 's' }),
+    ['<S-Tab>'] = cmp.mapping(function(fallback)
+      if cmp.visible() then
+        cmp.select_prev_item()
+      else
+        fallback()
+      end
+    end, { 'i', 's' }),
+  }),
+  sources = {
+    { name = 'nvim_lsp' },
+  },
+}
+
+-- Format files using LSP on save
+vim.api.nvim_create_autocmd('BufWritePre', {
+  callback = function(args)
+    vim.lsp.buf.format()
+  end,
+})
+
+-- Open LSP Diagnostics in quickfix list on save
+vim.api.nvim_create_autocmd('BufWritePost', {
+  callback = function(args)
+    vim.diagnostic.setqflist()
+  end,
+})
+
+--------------------------------------------------------------------------------
+-- Run 'organizeImports' on save for go files. Apparently organizing imports is
+-- considered a separate task than formatting, so it's implemented separately
+-- (in a much more cumbersome way, for some reason).
+-- https://github.com/golang/tools/blob/0b989c812dcb662451db0b70a8267fe7e211886e/gopls/doc/vim.md#neovim-imports
+-- https://github.com/golang/go/issues/33587
+--------------------------------------------------------------------------------
+
+vim.api.nvim_create_autocmd("BufWritePre", {
+  pattern = "*.go",
+  callback = function()
+    local params = vim.lsp.util.make_range_params()
+    params.context = {only = {"source.organizeImports"}}
+    -- buf_request_sync defaults to a 1000ms timeout. Depending on your
+    -- machine and codebase, you may want longer. Add an additional
+    -- argument after params if you find that you have to write the file
+    -- twice for changes to be saved.
+    -- E.g., vim.lsp.buf_request_sync(0, "textDocument/codeAction", params, 3000)
+    local result = vim.lsp.buf_request_sync(0, "textDocument/codeAction", params)
+    for cid, res in pairs(result or {}) do
+      for _, r in pairs(res.result or {}) do
+        if r.edit then
+          local enc = (vim.lsp.get_client_by_id(cid) or {}).offset_encoding or "utf-16"
+          vim.lsp.util.apply_workspace_edit(r.edit, enc)
+        end
+      end
+    end
+    vim.lsp.buf.format({async = false})
+  end
+})
-- 
cgit v1.2.3