refactor(util): reuse timer handles in Debouncer

lua/pack.lua

@@ -187,17 +187,7 @@ function M.watch()
 
     local plugins_dir = vim.fs.joinpath(config_dir, "plugins")
 
-    local err_msg, err_name
-    watcher, err_msg, err_name = vim.uv.new_fs_event()
-    if not watcher then
-        log.error(
-            "Failed to create fs event watcher: %s (%s)",
-            err_msg,
-            err_name
-        )
-        return
-    end
-
+    watcher = assert(vim.uv.new_fs_event())
     reload = util.debounce(function(filename)
         local path = vim.fs.joinpath(plugins_dir, filename)
         if not vim.uv.fs_stat(path) then
@@ -211,7 +201,7 @@ function M.watch()
         end
     end, 100)
 
-    watcher:start(plugins_dir, {}, function(err, filename)
+    assert(watcher:start(plugins_dir, {}, function(err, filename)
         if err then
             log.error("Watch error: %s", err)
             return
@@ -220,7 +210,7 @@ function M.watch()
             return
         end
         reload:call(filename)
-    end)
+    end))
 end
 
 function M.unwatch()