diff --git a/package.json b/package.json
index ad7cf51..9d86a43 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,7 @@
   "devDependencies": {
     "airtap": "~1.0.0",
     "is-async-supported": "~1.2.0",
+    "object.assign": "~4.1.0",
     "run-series": "~1.1.4",
     "tape": "~4.9.0"
   },
diff --git a/test/node/debug.js b/test/node/debug.js
index ef5f69f..70df304 100644
--- a/test/node/debug.js
+++ b/test/node/debug.js
@@ -19,68 +19,87 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
+'use strict';
 var assert = require('assert');
-var util = require('../../');
+var ObjectAssign = require('object.assign');
 
-if (process.argv[2] === 'child')
-  child();
+var modeArgv = process.argv[2]
+var sectionArgv = process.argv[3]
+
+if (modeArgv === 'child')
+  child(sectionArgv);
 else
   parent();
 
 function parent() {
-  test('foo,tud,bar', true);
-  test('foo,tud', true);
-  test('tud,bar', true);
-  test('tud', true);
-  test('foo,bar', false);
-  test('', false);
+  test('foo,tud,bar', true, 'tud');
+  test('foo,tud', true, 'tud');
+  test('tud,bar', true, 'tud');
+  test('tud', true, 'tud');
+  test('foo,bar', false, 'tud');
+  test('', false, 'tud');
+
+  test('###', true, '###');
+  test('hi:)', true, 'hi:)');
+  test('f$oo', true, 'f$oo');
+  test('f$oo', false, 'f.oo');
+  test('no-bar-at-all', false, 'bar');
+
+  test('test-abc', true, 'test-abc');
+  test('test-a', false, 'test-abc');
+  test('test-*', true, 'test-abc');
+  test('test-*c', true, 'test-abc');
+  test('test-*abc', true, 'test-abc');
+  test('abc-test', true, 'abc-test');
+  test('a*-test', true, 'abc-test');
+  test('*-test', true, 'abc-test');
 }
 
-function test(environ, shouldWrite) {
+function test(environ, shouldWrite, section) {
   var expectErr = '';
-  if (shouldWrite) {
-    expectErr = 'TUD %PID%: this { is: \'a\' } /debugging/\n' +
-                'TUD %PID%: number=1234 string=asdf obj={"foo":"bar"}\n';
-  }
   var expectOut = 'ok\n';
-  var didTest = false;
 
   var spawn = require('child_process').spawn;
-  var child = spawn(process.execPath, [__filename, 'child'], {
-    env: { NODE_DEBUG: environ }
+  var child = spawn(process.execPath, [__filename, 'child', section], {
+    env: ObjectAssign(process.env, { NODE_DEBUG: environ })
   });
 
-  expectErr = expectErr.split('%PID%').join(child.pid);
+  if (shouldWrite) {
+    expectErr =
+      section.toUpperCase() + ' ' + child.pid + ': this { is: \'a\' } /debugging/\n' +
+        section.toUpperCase() + ' ' + child.pid + ': num=1 str=a obj={"foo":"bar"}\n';
+  }
 
   var err = '';
   child.stderr.setEncoding('utf8');
-  child.stderr.on('data', function(c) {
+  child.stderr.on('data', function (c) {
     err += c;
   });
 
   var out = '';
   child.stdout.setEncoding('utf8');
-  child.stdout.on('data', function(c) {
+  child.stdout.on('data', function (c) {
     out += c;
   });
 
-  child.on('close', function(c) {
+  var didTest = false;
+  child.on('close', function (c) {
     assert(!c);
-    assert.equal(err, expectErr);
-    assert.equal(out, expectOut);
+    assert.strictEqual(err, expectErr);
+    assert.strictEqual(out, expectOut);
     didTest = true;
-    console.log('ok %j %j', environ, shouldWrite);
   });
 
-  process.on('exit', function() {
+  process.on('exit', function () {
     assert(didTest);
   });
 }
 
 
-function child() {
-  var debug = util.debuglog('tud');
+function child(section) {
+  var util = require('../../util');
+  var debug = util.debuglog(section);
   debug('this', { is: 'a' }, /debugging/);
-  debug('number=%d string=%s obj=%j', 1234, 'asdf', { foo: 'bar' });
+  debug('num=%d str=%s obj=%j', 1, 'a', { foo: 'bar' });
   console.log('ok');
 }
diff --git a/util.js b/util.js
index 6aad97c..6eea657 100644
--- a/util.js
+++ b/util.js
@@ -104,13 +104,20 @@ exports.deprecate = function(fn, msg) {
 
 
 var debugs = {};
-var debugEnviron;
+var debugEnvRegex = /^$/;
+
+if (process.env.NODE_DEBUG) {
+  var debugEnv = process.env.NODE_DEBUG;
+  debugEnv = debugEnv.replace(/[|\\{}()[\]^$+?.]/g, '\\$&')
+    .replace(/\*/g, '.*')
+    .replace(/,/g, '$|^')
+    .toUpperCase();
+  debugEnvRegex = new RegExp('^' + debugEnv + '$', 'i');
+}
 exports.debuglog = function(set) {
-  if (isUndefined(debugEnviron))
-    debugEnviron = process.env.NODE_DEBUG || '';
   set = set.toUpperCase();
   if (!debugs[set]) {
-    if (new RegExp('\\b' + set + '\\b', 'i').test(debugEnviron)) {
+    if (debugEnvRegex.test(set)) {
       var pid = process.pid;
       debugs[set] = function() {
         var msg = exports.format.apply(exports, arguments);