diff -r 000000000000 -r 6474c204b198 python/mozbuild/mozpack/test/test_path.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/python/mozbuild/mozpack/test/test_path.py	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,123 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+from mozpack.path import (
+    relpath,
+    join,
+    normpath,
+    dirname,
+    commonprefix,
+    basename,
+    split,
+    splitext,
+    basedir,
+    match,
+    rebase,
+)
+import unittest
+import mozunit
+import os
+
+
+class TestPath(unittest.TestCase):
+    def test_relpath(self):
+        self.assertEqual(relpath('foo', 'foo'), '')
+        self.assertEqual(relpath(os.path.join('foo', 'bar'), 'foo/bar'), '')
+        self.assertEqual(relpath(os.path.join('foo', 'bar'), 'foo'), 'bar')
+        self.assertEqual(relpath(os.path.join('foo', 'bar', 'baz'), 'foo'),
+                         'bar/baz')
+        self.assertEqual(relpath(os.path.join('foo', 'bar'), 'foo/bar/baz'),
+                         '..')
+        self.assertEqual(relpath(os.path.join('foo', 'bar'), 'foo/baz'),
+                         '../bar')
+        self.assertEqual(relpath('foo/', 'foo'), '')
+        self.assertEqual(relpath('foo/bar/', 'foo'), 'bar')
+
+    def test_join(self):
+        self.assertEqual(join('foo', 'bar', 'baz'), 'foo/bar/baz')
+        self.assertEqual(join('foo', '', 'bar'), 'foo/bar')
+        self.assertEqual(join('', 'foo', 'bar'), 'foo/bar')
+        self.assertEqual(join('', 'foo', '/bar'), '/bar')
+
+    def test_normpath(self):
+        self.assertEqual(normpath(os.path.join('foo', 'bar', 'baz',
+                                               '..', 'qux')), 'foo/bar/qux')
+
+    def test_dirname(self):
+        self.assertEqual(dirname('foo/bar/baz'), 'foo/bar')
+        self.assertEqual(dirname('foo/bar'), 'foo')
+        self.assertEqual(dirname('foo'), '')
+        self.assertEqual(dirname('foo/bar/'), 'foo/bar')
+
+    def test_commonprefix(self):
+        self.assertEqual(commonprefix([os.path.join('foo', 'bar', 'baz'),
+                                       'foo/qux', 'foo/baz/qux']), 'foo/')
+        self.assertEqual(commonprefix([os.path.join('foo', 'bar', 'baz'),
+                                       'foo/qux', 'baz/qux']), '')
+
+    def test_basename(self):
+        self.assertEqual(basename('foo/bar/baz'), 'baz')
+        self.assertEqual(basename('foo/bar'), 'bar')
+        self.assertEqual(basename('foo'), 'foo')
+        self.assertEqual(basename('foo/bar/'), '')
+
+    def test_split(self):
+        self.assertEqual(split(os.path.join('foo', 'bar', 'baz')),
+                         ['foo', 'bar', 'baz'])
+
+    def test_splitext(self):
+        self.assertEqual(splitext(os.path.join('foo', 'bar', 'baz.qux')),
+                         ('foo/bar/baz', '.qux'))
+
+    def test_basedir(self):
+        foobarbaz = os.path.join('foo', 'bar', 'baz')
+        self.assertEqual(basedir(foobarbaz, ['foo', 'bar', 'baz']), 'foo')
+        self.assertEqual(basedir(foobarbaz, ['foo', 'foo/bar', 'baz']),
+                         'foo/bar')
+        self.assertEqual(basedir(foobarbaz, ['foo/bar', 'foo', 'baz']),
+                         'foo/bar')
+        self.assertEqual(basedir(foobarbaz, ['foo', 'bar', '']), 'foo')
+        self.assertEqual(basedir(foobarbaz, ['bar', 'baz', '']), '')
+
+    def test_match(self):
+        self.assertTrue(match('foo', ''))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/bar'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo'))
+        self.assertTrue(match('foo', '*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/bar/*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/bar/*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/bar/*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/bar/*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/*/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '*/bar/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '*/*/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '*/*/*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/*/*'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/*/*.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/b*/*z.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/b*r/ba*z.qux'))
+        self.assertFalse(match('foo/bar/baz.qux', 'foo/b*z/ba*r.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '**'))
+        self.assertTrue(match('foo/bar/baz.qux', '**/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '**/bar/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/**/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/**/*.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '**/foo/bar/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/**/bar/baz.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/**/bar/*.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/**/*.qux'))
+        self.assertTrue(match('foo/bar/baz.qux', '**/*.qux'))
+        self.assertFalse(match('foo/bar/baz.qux', '**.qux'))
+        self.assertFalse(match('foo/bar', 'foo/*/bar'))
+        self.assertTrue(match('foo/bar/baz.qux', 'foo/**/bar/**'))
+        self.assertFalse(match('foo/nobar/baz.qux', 'foo/**/bar/**'))
+        self.assertTrue(match('foo/bar', 'foo/**/bar/**'))
+
+    def test_rebase(self):
+        self.assertEqual(rebase('foo', 'foo/bar', 'bar/baz'), 'baz')
+        self.assertEqual(rebase('foo', 'foo', 'bar/baz'), 'bar/baz')
+        self.assertEqual(rebase('foo/bar', 'foo', 'baz'), 'bar/baz')
+
+if __name__ == '__main__':
+    mozunit.main()