Restore test_socket IDNATest with working domain name (jython#260)

The test failed previously because the site used in the test did not exist and
testGetAddrInfoIDNAHostname must resolve it in DNS. We find another site that will hopefully exist for a while.

The change re-enables `test_socket` in CI, but with skips on posix for still-failing tests (not related to IDN).

Lib/test/test_socket.py

@@ -4,8 +4,6 @@
 from test import test_support
 
 import errno
-import gc
-import jarray
 import Queue
 import platform
 import pprint
@@ -884,6 +882,8 @@ def _testInheritedOption(self, level, option, values):
         except Exception, x:
             self.fail("Inherited option should not have raised exception: %s" % str(x))
 
+@unittest.skipIf(test_support.is_jython_posix,
+                 "Failing, possible race during close()-open().")
 class TestSupportedOptions(TestSocketOptions):
 
     def testSO_BROADCAST(self):
@@ -2397,8 +2397,11 @@ def _testUnicodeHostname(self):
 
 class IDNATest(unittest.TestCase):
 
+    # This site must exist in DNS as an IDN, hopefully with a long future.
+    DOMAIN = u'\u043c\u0430\u0442\u0435\u043c\u0430\u0442\u0438\u043a\u0430.\u0443\u043a\u0440'
+
     def testGetAddrInfoIDNAHostname(self):
-        idna_domain = u"al\u00e1n.com"
+        idna_domain = IDNATest.DOMAIN
         if socket.supports('idna'):
             try:
                 addresses = socket.getaddrinfo(idna_domain, 80)
@@ -2416,7 +2419,7 @@ def testGetAddrInfoIDNAHostname(self):
                 self.fail("Non ascii domain '%s' should have raised UnicodeEncodeError: no exception raised" % repr(idna_domain))
 
     def testAddrTupleIDNAHostname(self):
-        idna_domain = u"al\u00e1n.com"
+        idna_domain = IDNATest.DOMAIN
         s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
         if socket.supports('idna'):
             try:

build.xml

@@ -1511,7 +1511,6 @@ The text for an official release would continue like ...
             <arg value="test_py_compile"/> <!-- test_relative_path (on osx) -->
             <arg value="test_select_new"/>
             <arg value="test_smtpnet"/>
-            <arg value="test_socket"/>
         </exec>
     </target>
 
@@ -1532,7 +1531,6 @@ The text for an official release would continue like ...
             <arg value="test_os_jy"/> <!-- locale command (on git bash) -->
             <arg value="test_select_new"/>
             <arg value="test_smtpnet"/>
-            <arg value="test_socket"/>
         </exec>
     </target>