util: access process states lazily in debuglog

`debuglog()` depends on `process.pid` and `process.env.NODE_DEBUG`,
so it needs to be called lazily in top scopes of internal modules
that may be loaded before these run time states are allowed to
be accessed. This patch makes its implementation lazy by default,
the process states are only accessed when the returned debug
function is called for the first time.

PR-URL: https://github.com/nodejs/node/pull/27281
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Yongsheng Zhang <zyszys98@gmail.com>

1 files changed, 1 insertions, 8 deletions

diff --git a/lib/_stream_readable.js b/lib/_stream_readable.js
index 1b6f2175ce..34118f4fbe 100644
--- a/lib/_stream_readable.js
+++ b/lib/_stream_readable.js
@@ -30,14 +30,7 @@ const EE = require('events');
 const Stream = require('stream');
 const { Buffer } = require('buffer');
 
-let debuglog;
-function debug(...args) {
-  if (!debuglog) {
-    debuglog = require('internal/util/debuglog').debuglog('stream');
-  }
-  debuglog(...args);
-}
-
+const debug = require('internal/util/debuglog').debuglog('stream');
 const BufferList = require('internal/streams/buffer_list');
 const destroyImpl = require('internal/streams/destroy');
 const { getHighWaterMark } = require('internal/streams/state');