perf: async rustc unpretty command

Author: mrcjkb

lua/rustaceanvim/cargo.lua

@@ -127,21 +127,21 @@ function cargo.get_config_root_dir(config, file_name, callback)
   end
 end
 
----@param buf_name? string
----@return string edition
-function cargo.get_rustc_edition(buf_name)
+---@param callback fun(edition: string)
+function cargo.get_rustc_edition(callback)
   local config = require('rustaceanvim.config.internal')
-  buf_name = buf_name or vim.api.nvim_buf_get_name(0)
+  local buf_name = vim.api.nvim_buf_get_name(0)
   local path = vim.fs.dirname(buf_name)
-  local _, cargo_metadata = get_cargo_metadata(path)
-  local default_edition = config.tools.rustc.default_edition
-  if not cargo_metadata then
-    return default_edition
-  end
-  local package = vim.iter(cargo_metadata.packages or {}):find(function(pkg)
-    return type(pkg.edition) == 'string'
+  get_cargo_metadata(path, function(_, cargo_metadata)
+    local default_edition = config.tools.rustc.default_edition
+    if not cargo_metadata then
+      return callback(default_edition)
+    end
+    local pkg = vim.iter(cargo_metadata.packages or {}):find(function(p)
+      return type(p.edition) == 'string'
+    end)
+    return callback(pkg and pkg.edition or default_edition)
   end)
-  return package and package.edition or default_edition
 end
 
 return cargo

lua/rustaceanvim/commands/rustc_unpretty.lua

@@ -135,18 +135,20 @@ function M.rustc_unpretty(level)
   end
   text = table.concat(b, '\n')
 
-  vim.system({
-    rustc,
-    '--crate-type',
-    'lib',
-    '--edition',
-    cargo.get_rustc_edition(),
-    '-Z',
-    'unstable-options',
-    '-Z',
-    'unpretty=' .. level,
-    '-',
-  }, { stdin = text }, vim.schedule_wrap(handler))
+  cargo.get_rustc_edition(function(edition)
+    vim.system({
+      rustc,
+      '--crate-type',
+      'lib',
+      '--edition',
+      edition,
+      '-Z',
+      'unstable-options',
+      '-Z',
+      'unpretty=' .. level,
+      '-',
+    }, { stdin = text }, vim.schedule_wrap(handler))
+  end)
 end
 
 return M