From 97900776bb3611877d126aa58743eb9b5b2a4be8 Mon Sep 17 00:00:00 2001
From: Ben Noordhuis <info@bnoordhuis.nl>
Date: Wed, 14 Dec 2011 13:28:51 +0100
Subject: [PATCH] util: add internal function _deprecationWarning()

---
 lib/os.js   |  8 ++------
 lib/sys.js  | 11 ++---------
 lib/util.js | 16 ++++++++++++++++
 3 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/lib/os.js b/lib/os.js
index fa8ac01513..f226e3ecbf 100644
--- a/lib/os.js
+++ b/lib/os.js
@@ -37,12 +37,8 @@ exports.platform = function() {
   return process.platform;
 };
 
-var warnNetworkInterfaces = true;
 exports.getNetworkInterfaces = function() {
-  if (warnNetworkInterfaces) {
-    console.error("os.getNetworkInterfaces() is deprecated - use os.networkInterfaces()");
-    console.trace();
-    warnNetworkInterfaces = false;
-  }
+  require('util')._deprecationWarning('os',
+    'os.getNetworkInterfaces() is deprecated - use os.networkInterfaces()');
   return exports.networkInterfaces();
 };
diff --git a/lib/sys.js b/lib/sys.js
index d53a3dd95e..0039b89d20 100644
--- a/lib/sys.js
+++ b/lib/sys.js
@@ -21,15 +21,8 @@
 
 var util = require('util');
 
-var sysWarning;
-if (!sysWarning) {
-  sysWarning = 'The "sys" module is now called "util". ' +
-               'It should have a similar interface.';
-  if (process.env.NODE_DEBUG && process.env.NODE_DEBUG.indexOf('sys') != -1)
-    console.trace(sysWarning);
-  else
-    console.error(sysWarning);
-}
+util._deprecationWarning('sys',
+  'The "sys" module is now called "util". It should have a similar interface.');
 
 exports.print = util.print;
 exports.puts = util.puts;
diff --git a/lib/util.js b/lib/util.js
index b00da2de9d..cd4cc0e964 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -518,3 +518,19 @@ exports.inherits = function(ctor, superCtor) {
     }
   });
 };
+
+var deprecationWarnings;
+
+exports._deprecationWarning = function(moduleId, message) {
+  if (!deprecationWarnings)
+    deprecationWarnings = {};
+  else if (message in deprecationWarnings)
+    return;
+
+  deprecationWarnings[message] = true;
+
+  if ((new RegExp('\\b' + moduleId + '\\b')).test(process.env.NODE_DEBUG))
+    console.trace(message);
+  else
+    console.error(message);
+};