Add Executor.join_async() method

lua/obsidian/async.lua

@@ -88,27 +88,42 @@ Executor.map = function(self, fn, task_args, callback)
   end
 end
 
----Block Neovim until all currently running tasks have completed, waiting at most `timeout` milliseconds
----before raising a timeout error.
----
----This is useful in testing, but in general you want to avoid blocking Neovim.
----
 ---@param self obsidian.Executor
 ---@param timeout integer|?
-Executor.join = function(self, timeout)
+---@param pause_fn function(integer)
+Executor._join = function(self, timeout, pause_fn)
   local start_time = uv.uptime()
   local pause_for = 100
   if timeout ~= nil then
     pause_for = math.min(timeout / 2, pause_for)
   end
   while self.tasks_running > 0 do
-    vim.wait(pause_for)
+    pause_fn(pause_for)
     if timeout ~= nil and uv.uptime() - start_time > timeout then
       error "Timeout error from AsyncExecutor.join()"
     end
   end
 end
 
+---Block Neovim until all currently running tasks have completed, waiting at most `timeout` milliseconds
+---before raising a timeout error.
+---
+---This is useful in testing, but in general you want to avoid blocking Neovim.
+---
+---@param self obsidian.Executor
+---@param timeout integer|?
+Executor.join = function(self, timeout)
+  self:_join(timeout, vim.wait)
+end
+
+---An async version of `.join()`.
+---
+---@param self obsidian.Executor
+---@param timeout integer|?
+Executor.join_async = function(self, timeout)
+  self:_join(timeout, async.util.sleep)
+end
+
 ---An Executor that uses coroutines to run user functions concurrently.
 ---@class obsidian.AsyncExecutor : obsidian.Executor
 ---@field tasks_running integer