test_crawl: make mock server print a line when ready, and wait for that line to start tests, instead of waiting for an arbitrary time

scrapy/tests/mockserver.py

@@ -77,7 +77,12 @@ class Root(Resource):
         return 'Scrapy mock HTTP server\n'
 
 
-root = Root()
-factory = Site(root)
-reactor.listenTCP(8998, factory)
-reactor.run()
+if __name__ == "__main__":
+    root = Root()
+    factory = Site(root)
+    port = reactor.listenTCP(8998, factory, interface="127.0.0.1")
+    def print_listening():
+        h = port.getHost()
+        print "Mock server running at http://%s:%d" % (h.host, h.port)
+    reactor.callWhenRunning(print_listening)
+    reactor.run()

scrapy/tests/test_crawl.py

@@ -1,7 +1,7 @@
 import sys, time
 from twisted.internet import defer
 from twisted.trial.unittest import TestCase, SkipTest
-from subprocess import Popen
+from subprocess import Popen, PIPE
 from scrapy.spider import BaseSpider
 from scrapy.http import Request
 from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
@@ -32,8 +32,8 @@ def docrawl(spider, settings=None):
 class CrawlTestCase(TestCase):
 
     def setUp(self):
-        self.proc = Popen([sys.executable, '-m', 'scrapy.tests.mockserver'])
-        time.sleep(0.5)
+        self.proc = Popen([sys.executable, '-u', '-m', 'scrapy.tests.mockserver'], stdout=PIPE)
+        self.proc.stdout.readline()
 
     def tearDown(self):
         self.proc.kill()