moved debug fn out to own module, added tests

lib/appenders/gelf.js

@@ -4,6 +4,7 @@ var layouts = require('../layouts');
 var levels = require('../levels');
 var dgram = require('dgram');
 var util = require('util');
+var debug = require('../debug')('GELF Appender');
 
 var LOG_EMERG=0;    // system is unusable
 var LOG_ALERT=1;    // action must be taken immediately
@@ -24,13 +25,6 @@ levelMapping[levels.WARN] = LOG_WARNING;
 levelMapping[levels.ERROR] = LOG_ERR;
 levelMapping[levels.FATAL] = LOG_CRIT;
 
-var debug;
-if (process.env.NODE_DEBUG && /\blog4js\b/.test(process.env.NODE_DEBUG)) {
-  debug = function(message) { console.error('LOG4JS: (GELF Appender) %s', message); };
-} else {
-  debug = function() { };
-}
-
 /**
  * GELF appender that supports sending UDP packets to a GELF compatible server such as Graylog
  *

lib/debug.js

@@ -0,0 +1,15 @@
+"use strict";
+
+module.exports = function(label) {
+  var debug;
+
+  if (process.env.NODE_DEBUG && /\blog4js\b/.test(process.env.NODE_DEBUG)) {
+    debug = function(message) { 
+      console.error('LOG4JS: (%s) %s', label, message); 
+    };
+  } else {
+    debug = function() { };
+  }
+
+  return debug;
+};

lib/streams/BaseRollingFileStream.js

@@ -1,6 +1,7 @@
 "use strict";
 var fs = require('fs')
 , stream
+, debug = require('../debug')('BaseRollingFileStream')
 , util = require('util')
 , semver = require('semver');
 
@@ -10,13 +11,6 @@ if (semver.satisfies(process.version, '>=0.10.0')) {
   stream = require('readable-stream');
 }
 
-var debug;
-if (process.env.NODE_DEBUG && /\blog4js\b/.test(process.env.NODE_DEBUG)) {
-  debug = function(message) { console.error('LOG4JS: (BaseRollingFileStream) %s', message); };
-} else {
-  debug = function() { };
-}
-
 module.exports = BaseRollingFileStream;
 
 function BaseRollingFileStream(filename, options) {

lib/streams/DateRollingFileStream.js

@@ -1,5 +1,6 @@
 "use strict";
 var BaseRollingFileStream = require('./BaseRollingFileStream')
+, debug = require('../debug')('DateRollingFileStream')
 , format = require('../date_format')
 , async = require('async')
 , fs = require('fs')
@@ -7,13 +8,6 @@ var BaseRollingFileStream = require('./BaseRollingFileStream')
 
 module.exports = DateRollingFileStream;
 
-var debug;
-if (process.env.NODE_DEBUG && /\blog4js\b/.test(process.env.NODE_DEBUG)) {
-  debug = function(message) { console.error('LOG4JS: (DateRollingFileStream) %s', message); };
-} else {
-  debug = function() { };
-}
-
 function DateRollingFileStream(filename, pattern, options, now) {
   debug("Now is " + now);
   if (pattern && typeof(pattern) === 'object') {

lib/streams/RollingFileStream.js

@@ -1,17 +1,11 @@
 "use strict";
 var BaseRollingFileStream = require('./BaseRollingFileStream')
+, debug = require('../debug')('RollingFileStream')
 , util = require('util')
 , path = require('path')
 , fs = require('fs')
 , async = require('async');
 
-var debug;
-if (process.env.NODE_DEBUG && /\blog4js\b/.test(process.env.NODE_DEBUG)) {
-  debug = function(message) { console.error('LOG4JS: (RollingFileStream) %s', message); };
-} else {
-  debug = function() { };
-}
-
 module.exports = RollingFileStream;
 
 function RollingFileStream (filename, size, backups, options) {

test/debug-test.js

@@ -0,0 +1,72 @@
+"use strict";
+var vows = require('vows')
+, assert = require('assert')
+, sandbox = require('sandboxed-module')
+, fakeConsole = {
+  error: function(format, label, message) {
+    this.logged = [ format, label, message ];
+  }
+}
+, globals = function(debugValue) {
+  return {
+    process: {
+      env: {
+        'NODE_DEBUG': debugValue
+      }
+    },
+    console: fakeConsole
+  };
+};
+
+vows.describe('../lib/debug').addBatch({
+  'when NODE_DEBUG is set to log4js': {
+    topic: function() {
+      var debug = sandbox.require(
+        '../lib/debug', 
+        { 'globals': globals('log4js') }
+      );
+
+      fakeConsole.logged = [];
+      debug('cheese')('biscuits');
+      return fakeConsole.logged;
+    },
+    'it should log to console.error': function(logged) {
+      assert.equal(logged[0], 'LOG4JS: (%s) %s');
+      assert.equal(logged[1], 'cheese');
+      assert.equal(logged[2], 'biscuits');
+    }
+  },
+
+  'when NODE_DEBUG is set to not log4js': {
+    topic: function() {
+      var debug = sandbox.require(
+        '../lib/debug',
+        { globals: globals('other_module') }
+      );
+
+      fakeConsole.logged = [];
+      debug('cheese')('biscuits');
+      return fakeConsole.logged;
+    },
+    'it should not log to console.error': function(logged) {
+      assert.equal(logged.length, 0);
+    }
+  },
+
+  'when NODE_DEBUG is not set': {
+    topic: function() {
+      var debug = sandbox.require(
+        '../lib/debug',
+        { globals: globals(null) }
+      );
+
+      fakeConsole.logged = [];
+      debug('cheese')('biscuits');
+      return fakeConsole.logged;
+    },
+    'it should not log to console.error': function(logged) {
+      assert.equal(logged.length, 0);
+    }
+  }
+
+}).exportTo(module);