fix test running for OS X 10.8

It used to work on OS X 10.7, but in 10.8 splash requires
more time to start and this makes all tests fail.

splash/tests/test_render.py

@@ -3,6 +3,17 @@
 from PIL import Image
 from splash.tests.utils import TestServers
 
+class TestTestUtils(unittest.TestCase):
+
+    def test_mockserver_works(self):
+        r = requests.get('http://localhost:8998/jsrender')
+        self.assertEqual(r.status_code, 200)
+
+    def test_splashserver_works(self):
+        r = requests.get('http://localhost:8050/debug')
+        self.assertEqual(r.status_code, 200)
+
+
 class _RenderTest(unittest.TestCase):
 
     host = "localhost:8050"

splash/tests/utils.py

@@ -21,7 +21,11 @@ def __enter__(self):
             msg = "unable to start splash server. error code: %d - stderr follows: \n%s" % \
                 (self.proc.returncode, self.proc.stderr.read())
             raise RuntimeError(msg)
+
+        # wait until server starts writing debug messages,
+        # then wait a bit more to make it more likely to be online
         self.proc.stderr.readline()
+        time.sleep(0.2)
 
     def __exit__(self, exc_type, exc_value, traceback):
         self.proc.kill()
@@ -35,6 +39,7 @@ def __enter__(self):
         self.proc = Popen([sys.executable, '-u', '-m', 'splash.tests.mockserver'],
             stdout=PIPE, env=get_testenv())
         self.proc.stdout.readline()
+        time.sleep(0.1)
 
     def __exit__(self, exc_type, exc_value, traceback):
         self.proc.kill()