feat: support default indent

Author: wsdjeg

lua/format/init.lua

@@ -85,6 +85,12 @@ function M.format(bang, user_input, start_line, end_line, opts)
     end
   end
 
+  local indent = 0
+
+  if start_line > 1 then
+    indent = vim.fn.matchstr(vim.fn.getline(start_line - 1), '^\\s*')
+  end
+
   task.run({
     bufnr = vim.fn.bufnr(),
     stdin = vim.api.nvim_buf_get_lines(0, start_line - 1, end_line, false),
@@ -94,6 +100,7 @@ function M.format(bang, user_input, start_line, end_line, opts)
     timeout = timeout,
     hooks = opts.hooks,
     lock_buf = opts.lock_buf,
+    indent = indent,
   })
 end
 

lua/format/task.lua

@@ -40,6 +40,13 @@ local function on_exit(id, code, single)
     else
       formatted_context = stdout
     end
+    if #current_task.indent > 0 then
+      formatted_context = (function()
+        return vim.tbl_map(function(t)
+          return current_task.indent .. t
+        end, formatted_context)
+      end)()
+    end
     if table.concat(formatted_context, '\n') == table.concat(current_task.stdin, '\n') then
       util.msg('no necessary changes')
     else