synchronous goimports (#186)

* fix save formatting

* fix vim.lsp.buf.format polyfill

* reformat and default values

* remove extra end

Co-authored-by: rayx <rayx.cn@gmail.com>

lua/go/format.lua

@@ -137,9 +137,13 @@ end
 M.org_imports = function(wait_ms)
   local codeaction = require("go.lsp").codeaction
   codeaction("", "source.organizeImports", wait_ms)
-  vim.defer_fn(function()
-    vim.lsp.buf.format({ async = _GO_NVIM_CFG.lsp_fmt_async })
-  end, 100)
+  if _GO_NVIM_CFG.lsp_fmt_async then
+    vim.defer_fn(function()
+      vim.lsp.buf.format({ async = true })
+    end, 100)
+  else
+    vim.lsp.buf.format({ async = false })
+  end
 end
 
 M.goimport = function(...)

lua/go/lsp.lua

@@ -8,7 +8,12 @@ end
 
 if vim.lsp.buf.format == nil then
   -- neovim < 0.7 only
-  vim.lsp.buf.format = vim.lsp.buf.formatting
+  vim.lsp.buf.format = function(options)
+  if options.async then
+    vim.lsp.buf.formatting()
+  else
+    vim.lsp.buf.formatting_sync()
+  end
 end
 
 local codelens_enabled = false