Test cleanup.

Tests pass or fail gracefully on older PostgreSQL versions.

If unittest2 is available, skip tests instead of printing warnings.

13 files changed, 222 insertions, 122 deletions

diff --git a/tests/__init__.py b/tests/__init__.py
index 1c8f6f2..2319341 100755
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 
 import os
-import unittest
+from testutils import unittest
 
 dbname = os.environ.get('PSYCOPG2_TESTDB', 'psycopg2_test')
 dbhost = os.environ.get('PSYCOPG2_TESTDB_HOST', None)
@@ -59,14 +59,8 @@ def test_suite():
     suite.addTest(test_transaction.test_suite())
     suite.addTest(types_basic.test_suite())
     suite.addTest(types_extras.test_suite())
-
-    if not green:
-        suite.addTest(test_lobject.test_suite())
-        suite.addTest(test_copy.test_suite())
-    else:
-        import warnings
-        warnings.warn("copy/lobjects not implemented in green mode: skipping tests")
-
+    suite.addTest(test_lobject.test_suite())
+    suite.addTest(test_copy.test_suite())
     suite.addTest(test_notify.test_suite())
     suite.addTest(test_async.test_suite())
     suite.addTest(test_green.test_suite())
diff --git a/tests/extras_dictcursor.py b/tests/extras_dictcursor.py
index 6bc5cad..a0583c5 100644
--- a/tests/extras_dictcursor.py
+++ b/tests/extras_dictcursor.py
@@ -16,7 +16,7 @@
 
 import psycopg2
 import psycopg2.extras
-import unittest
+from testutils import unittest
 
 import tests
 
@@ -111,8 +111,7 @@ def if_has_namedtuple(f):
         try:
             from collections import namedtuple
         except ImportError:
-            import warnings
-            warnings.warn("collections.namedtuple not available")
+            return self.skipTest("collections.namedtuple not available")
         else:
             return f(self)
 
@@ -133,8 +132,9 @@ class NamedTupleCursorTest(unittest.TestCase):
             connection_factory=NamedTupleConnection)
         curs = self.conn.cursor()
         curs.execute("CREATE TEMPORARY TABLE nttest (i int, s text)")
-        curs.execute(
-            "INSERT INTO nttest VALUES (1, 'foo'), (2, 'bar'), (3, 'baz')")
+        curs.execute("INSERT INTO nttest VALUES (1, 'foo')")
+        curs.execute("INSERT INTO nttest VALUES (2, 'bar')")
+        curs.execute("INSERT INTO nttest VALUES (3, 'baz')")
         self.conn.commit()
 
     @if_has_namedtuple
diff --git a/tests/test_async.py b/tests/test_async.py
index 9187cec..c839604 100755
--- a/tests/test_async.py
+++ b/tests/test_async.py
@@ -1,5 +1,5 @@
 #!/usr/bin/env python
-import unittest
+from testutils import unittest
 
 import psycopg2
 from psycopg2 import extensions
@@ -98,14 +98,13 @@ class AsyncTests(unittest.TestCase):
         cur = self.conn.cursor()
         try:
             cur.callproc("pg_sleep", (0.1, ))
-        except psycopg2.ProgrammingError:
-            # PG <8.1 did not have pg_sleep
-            return
-        self.assertTrue(self.conn.isexecuting())
+            self.assertTrue(self.conn.isexecuting())
 
-        self.wait(cur)
-        self.assertFalse(self.conn.isexecuting())
-        self.assertEquals(cur.fetchall()[0][0], '')
+            self.wait(cur)
+            self.assertFalse(self.conn.isexecuting())
+            self.assertEquals(cur.fetchall()[0][0], '')
+        except psycopg2.ProgrammingError:
+            return self.skipTest("PG < 8.1 did not have pg_sleep")
 
     def test_async_after_async(self):
         cur = self.conn.cursor()
@@ -213,7 +212,11 @@ class AsyncTests(unittest.TestCase):
 
         cur.execute("begin")
         self.wait(cur)
-        cur.execute("insert into table1 values (1), (2), (3)")
+        cur.execute("""
+            insert into table1 values (1);
+            insert into table1 values (2);
+            insert into table1 values (3);
+        """)
         self.wait(cur)
         cur.execute("select id from table1 order by id")
 
@@ -247,7 +250,11 @@ class AsyncTests(unittest.TestCase):
 
     def test_async_scroll(self):
         cur = self.conn.cursor()
-        cur.execute("insert into table1 values (1), (2), (3)")
+        cur.execute("""
+            insert into table1 values (1);
+            insert into table1 values (2);
+            insert into table1 values (3);
+        """)
         self.wait(cur)
         cur.execute("select id from table1 order by id")
 
@@ -279,7 +286,11 @@ class AsyncTests(unittest.TestCase):
     def test_scroll(self):
         cur = self.sync_conn.cursor()
         cur.execute("create table table1 (id int)")
-        cur.execute("insert into table1 values (1), (2), (3)")
+        cur.execute("""
+            insert into table1 values (1);
+            insert into table1 values (2);
+            insert into table1 values (3);
+        """)
         cur.execute("select id from table1 order by id")
         cur.scroll(2)
         cur.scroll(-1)
diff --git a/tests/test_connection.py b/tests/test_connection.py
index 36ce640..400ddd6 100644
--- a/tests/test_connection.py
+++ b/tests/test_connection.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 
-import unittest
+from testutils import unittest, decorate_all_tests
 from operator import attrgetter
 
 import psycopg2
@@ -82,13 +82,24 @@ class ConnectionTests(unittest.TestCase):
         conn = self.connect()
         self.assert_(conn.protocol_version in (2,3), conn.protocol_version)
 
+    def test_tpc_unsupported(self):
+        cnn = self.connect()
+        if cnn.server_version >= 80100:
+            return self.skipTest("tpc is supported")
+
+        self.assertRaises(psycopg2.NotSupportedError,
+            cnn.xid, 42, "foo", "bar")
+
 
 class IsolationLevelsTestCase(unittest.TestCase):
 
     def setUp(self):
         conn = self.connect()
         cur = conn.cursor()
-        cur.execute("drop table if exists isolevel;")
+        try:
+            cur.execute("drop table isolevel;")
+        except psycopg2.ProgrammingError:
+            conn.rollback()
         cur.execute("create table isolevel (id integer);")
         conn.commit()
         conn.close()
@@ -244,18 +255,16 @@ def skip_if_tpc_disabled(f):
         try:
             cur.execute("SHOW max_prepared_transactions;")
         except psycopg2.ProgrammingError:
-            # Server version too old: let's die a different death
-            mtp = 1
+            return self.skipTest(
+                "server too old: two phase transactions not supported.")
         else:
             mtp = int(cur.fetchone()[0])
         cnn.close()
 
         if not mtp:
-            import warnings
-            warnings.warn(
+            return self.skipTest(
                 "server not configured for two phase transactions. "
                 "set max_prepared_transactions to > 0 to run the test")
-            return
         return f(self)
 
     skip_if_tpc_disabled_.__name__ = f.__name__
@@ -274,9 +283,15 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         cnn = self.connect()
         cnn.set_isolation_level(0)
         cur = cnn.cursor()
-        cur.execute(
-            "select gid from pg_prepared_xacts where database = %s",
-            (tests.dbname,))
+        try:
+            cur.execute(
+                "select gid from pg_prepared_xacts where database = %s",
+                (tests.dbname,))
+        except psycopg2.ProgrammingError:
+            cnn.rollback()
+            cnn.close()
+            return
+
         gids = [ r[0] for r in cur ]
         for gid in gids:
             cur.execute("rollback prepared %s;", (gid,))
@@ -285,7 +300,10 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
     def make_test_table(self):
         cnn = self.connect()
         cur = cnn.cursor()
-        cur.execute("DROP TABLE IF EXISTS test_tpc;")
+        try:
+            cur.execute("DROP TABLE test_tpc;")
+        except psycopg2.ProgrammingError:
+            cnn.rollback()
         cur.execute("CREATE TABLE test_tpc (data text);")
         cnn.commit()
         cnn.close()
@@ -314,7 +332,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
     def connect(self):
         return psycopg2.connect(tests.dsn)
 
-    @skip_if_tpc_disabled
     def test_tpc_commit(self):
         cnn = self.connect()
         xid = cnn.xid(1, "gtrid", "bqual")
@@ -356,7 +373,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         self.assertEqual(0, self.count_xacts())
         self.assertEqual(1, self.count_test_records())
 
-    @skip_if_tpc_disabled
     def test_tpc_commit_recovered(self):
         cnn = self.connect()
         xid = cnn.xid(1, "gtrid", "bqual")
@@ -383,7 +399,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         self.assertEqual(0, self.count_xacts())
         self.assertEqual(1, self.count_test_records())
 
-    @skip_if_tpc_disabled
     def test_tpc_rollback(self):
         cnn = self.connect()
         xid = cnn.xid(1, "gtrid", "bqual")
@@ -425,7 +440,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         self.assertEqual(0, self.count_xacts())
         self.assertEqual(0, self.count_test_records())
 
-    @skip_if_tpc_disabled
     def test_tpc_rollback_recovered(self):
         cnn = self.connect()
         xid = cnn.xid(1, "gtrid", "bqual")
@@ -464,7 +478,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         xns = cnn.tpc_recover()
         self.assertEqual(psycopg2.extensions.STATUS_BEGIN, cnn.status)
 
-    @skip_if_tpc_disabled
     def test_recovered_xids(self):
         # insert a few test xns
         cnn = self.connect()
@@ -495,7 +508,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
             self.assertEqual(xid.owner, owner)
             self.assertEqual(xid.database, database)
 
-    @skip_if_tpc_disabled
     def test_xid_encoding(self):
         cnn = self.connect()
         xid = cnn.xid(42, "gtrid", "bqual")
@@ -508,7 +520,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
             (tests.dbname,))
         self.assertEqual('42_Z3RyaWQ=_YnF1YWw=', cur.fetchone()[0])
 
-    @skip_if_tpc_disabled
     def test_xid_roundtrip(self):
         for fid, gtrid, bqual in [
             (0, "", ""),
@@ -532,7 +543,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
 
             cnn.tpc_rollback(xid)
 
-    @skip_if_tpc_disabled
     def test_unparsed_roundtrip(self):
         for tid in [
             '',
@@ -585,7 +595,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         x2 = Xid.from_string('99_xxx_yyy')
         self.assertEqual(str(x2), '99_xxx_yyy')
 
-    @skip_if_tpc_disabled
     def test_xid_unicode(self):
         cnn = self.connect()
         x1 = cnn.xid(10, u'uni', u'code')
@@ -598,7 +607,6 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         self.assertEqual('uni', xid.gtrid)
         self.assertEqual('code', xid.bqual)
 
-    @skip_if_tpc_disabled
     def test_xid_unicode_unparsed(self):
         # We don't expect people shooting snowmen as transaction ids,
         # so if something explodes in an encode error I don't mind.
@@ -615,6 +623,8 @@ class ConnectionTwoPhaseTests(unittest.TestCase):
         self.assertEqual('transaction-id', xid.gtrid)
         self.assertEqual(None, xid.bqual)
 
+decorate_all_tests(ConnectionTwoPhaseTests, skip_if_tpc_disabled)
+
 
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)
diff --git a/tests/test_copy.py b/tests/test_copy.py
index 19fabe1..b0d9965 100644
--- a/tests/test_copy.py
+++ b/tests/test_copy.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 import os
 import string
-import unittest
+from testutils import unittest, decorate_all_tests
 from cStringIO import StringIO
 from itertools import cycle, izip
 
@@ -9,6 +9,15 @@ import psycopg2
 import psycopg2.extensions
 import tests
 
+def skip_if_green(f):
+    def skip_if_green_(self):
+        if tests.green:
+            return self.skipTest("copy in async mode currently not supported")
+        else:
+            return f(self)
+
+    return skip_if_green_
+
 
 class MinimalRead(object):
     """A file wrapper exposing the minimal interface to copy from."""
@@ -29,6 +38,7 @@ class MinimalWrite(object):
     def write(self, data):
         return self.f.write(data)
 
+
 class CopyTests(unittest.TestCase):
 
     def setUp(self):
@@ -124,6 +134,9 @@ class CopyTests(unittest.TestCase):
 
         self.assertEqual(ntests, len(string.letters))
 
+decorate_all_tests(CopyTests, skip_if_green)
+
+
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)
 
diff --git a/tests/test_lobject.py b/tests/test_lobject.py
index f4a684f..88e18d6 100644
--- a/tests/test_lobject.py
+++ b/tests/test_lobject.py
@@ -2,16 +2,33 @@
 import os
 import shutil
 import tempfile
-import unittest
-import warnings
+from testutils import unittest, decorate_all_tests
 
 import psycopg2
 import psycopg2.extensions
 import tests
 
+def skip_if_no_lo(f):
+    def skip_if_no_lo_(self):
+        if self.conn.server_version < 80100:
+            return self.skipTest("large objects only supported from PG 8.1")
+        else:
+            return f(self)
 
-class LargeObjectTests(unittest.TestCase):
+    return skip_if_no_lo_
 
+def skip_if_green(f):
+    def skip_if_green_(self):
+        if tests.green:
+            return self.skipTest("libpq doesn't support LO in async mode")
+        else:
+            return f(self)
+
+    return skip_if_green_
+
+
+class LargeObjectMixin(object):
+    # doesn't derive from TestCase to avoid repeating tests twice.
     def setUp(self):
         self.conn = psycopg2.connect(tests.dsn)
         self.lo_oid = None
@@ -30,6 +47,8 @@ class LargeObjectTests(unittest.TestCase):
                 lo.unlink()
         self.conn.close()
 
+
+class LargeObjectTests(LargeObjectMixin, unittest.TestCase):
     def test_create(self):
         lo = self.conn.lobject()
         self.assertNotEqual(lo, None)
@@ -261,30 +280,25 @@ class LargeObjectTests(unittest.TestCase):
         self.assertTrue(os.path.exists(filename))
         self.assertEqual(open(filename, "rb").read(), "some data")
 
+decorate_all_tests(LargeObjectTests, skip_if_no_lo)
+decorate_all_tests(LargeObjectTests, skip_if_green)
 
-class LargeObjectTruncateTests(LargeObjectTests):
-
-    skip = None
 
-    def setUp(self):
-        LargeObjectTests.setUp(self)
+def skip_if_no_truncate(f):
+    def skip_if_no_truncate_(self):
+        if self.conn.server_version < 80300:
+            return self.skipTest(
+                "the server doesn't support large object truncate")
 
-        if self.skip is None:
-            self.skip = False
-            if self.conn.server_version < 80300:
-                warnings.warn("Large object truncate tests skipped, "
-                              "the server does not support them")
-                self.skip = True
+        if not hasattr(psycopg2.extensions.lobject, 'truncate'):
+            return self.skipTest(
+                "psycopg2 has been built against a libpq "
+                "without large object truncate support.")
 
-            if not hasattr(psycopg2.extensions.lobject, 'truncate'):
-                warnings.warn("Large object truncate tests skipped, "
-                              "psycopg2 has been built against an old library")
-                self.skip = True
+        return f(self)
 
+class LargeObjectTruncateTests(LargeObjectMixin, unittest.TestCase):
     def test_truncate(self):
-        if self.skip:
-            return
-
         lo = self.conn.lobject()
         lo.write("some data")
         lo.close()
@@ -308,23 +322,22 @@ class LargeObjectTruncateTests(LargeObjectTests):
         self.assertEqual(lo.read(), "")
 
     def test_truncate_after_close(self):
-        if self.skip:
-            return
-
         lo = self.conn.lobject()
         lo.close()
         self.assertRaises(psycopg2.InterfaceError, lo.truncate)
 
     def test_truncate_after_commit(self):
-        if self.skip:
-            return
-
         lo = self.conn.lobject()
         self.lo_oid = lo.oid
         self.conn.commit()
 
         self.assertRaises(psycopg2.ProgrammingError, lo.truncate)
 
+decorate_all_tests(LargeObjectTruncateTests, skip_if_no_lo)
+decorate_all_tests(LargeObjectTruncateTests, skip_if_green)
+decorate_all_tests(LargeObjectTruncateTests, skip_if_no_truncate)
+
+
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)
 
diff --git a/tests/test_notify.py b/tests/test_notify.py
index 8dd8c70..75dae1e 100755
--- a/tests/test_notify.py
+++ b/tests/test_notify.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python
-import unittest
-import warnings
+from testutils import unittest
 
 import psycopg2
 from psycopg2 import extensions
@@ -127,9 +126,8 @@ conn.close()
 
     def test_notify_payload(self):
         if self.conn.server_version < 90000:
-            warnings.warn("server version %s doesn't support notify payload: skipping test"
+            return self.skipTest("server version %s doesn't support notify payload"
                 % self.conn.server_version)
-            return
         self.autocommit(self.conn)
         self.listen('foo')
         pid = int(self.notify('foo', payload="Hello, world!").communicate()[0])
diff --git a/tests/test_psycopg2_dbapi20.py b/tests/test_psycopg2_dbapi20.py
index 1d83f06..93fdfa6 100755
--- a/tests/test_psycopg2_dbapi20.py
+++ b/tests/test_psycopg2_dbapi20.py
@@ -2,7 +2,7 @@
 import dbapi20
 import dbapi20_tpc
 from test_connection import skip_if_tpc_disabled
-import unittest
+from testutils import unittest, decorate_all_tests
 import psycopg2
 
 import tests
@@ -23,19 +23,14 @@ class Psycopg2Tests(dbapi20.DatabaseAPI20Test):
         pass
 
 
-class Psycopg2TPCTests(dbapi20_tpc.TwoPhaseCommitTests):
+class Psycopg2TPCTests(dbapi20_tpc.TwoPhaseCommitTests, unittest.TestCase):
     driver = psycopg2
 
     def connect(self):
         return psycopg2.connect(dsn=tests.dsn)
 
-    @skip_if_tpc_disabled
-    def test_tpc_commit_with_prepare(self):
-        super(Psycopg2TPCTests, self).test_tpc_commit_with_prepare()
+decorate_all_tests(Psycopg2TPCTests, skip_if_tpc_disabled)
 
-    @skip_if_tpc_disabled
-    def test_tpc_rollback_with_prepare(self):
-        super(Psycopg2TPCTests, self).test_tpc_rollback_with_prepare()
 
 def test_suite():
     return unittest.TestLoader().loadTestsFromName(__name__)
diff --git a/tests/test_quote.py b/tests/test_quote.py
index 6da10fa..95c5d7a 100755
--- a/tests/test_quote.py
+++ b/tests/test_quote.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python
-import unittest
-import warnings
+from testutils import unittest
 
 import psycopg2
 import psycopg2.extensions
@@ -61,9 +60,9 @@ class QuotingTestCase(unittest.TestCase):
         curs.execute("SHOW server_encoding")
         server_encoding = curs.fetchone()[0]
         if server_encoding != "UTF8":
-            warnings.warn("Unicode test skipped since server encoding is %s"
-                          % server_encoding)
-            return
+            return self.skipTest(
+                "Unicode test skipped since server encoding is %s"
+                    % server_encoding)
 
         data = u"""some data with \t chars
         to escape into, 'quotes', \u20ac euro sign and \\ a backslash too.
diff --git a/tests/test_transaction.py b/tests/test_transaction.py
index 030bf17..3ee5ee7 100755
--- a/tests/test_transaction.py
+++ b/tests/test_transaction.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 import threading
-import unittest
+from testutils import unittest
 
 import psycopg2
 from psycopg2.extensions import (
@@ -215,8 +215,11 @@ class QueryCancellationTests(unittest.TestCase):
         curs = self.conn.cursor()
         # Set a low statement timeout, then sleep for a longer period.
         curs.execute('SET statement_timeout TO 10')
-        self.assertRaises(psycopg2.extensions.QueryCanceledError,
-                          curs.execute, 'SELECT pg_sleep(50)')
+        try:
+            self.assertRaises(psycopg2.extensions.QueryCanceledError,
+                              curs.execute, 'SELECT pg_sleep(50)')
+        except psycopg2.ProgrammingError:
+            return self.skipTest("pg_sleep not available")
 
 
 def test_suite():
diff --git a/tests/testutils.py b/tests/testutils.py
new file mode 100644
index 0000000..c047827
--- /dev/null
+++ b/tests/testutils.py
@@ -0,0 +1,46 @@
+# Utility module for psycopg2 testing.
+# 
+# Copyright (C) 2010 Daniele Varrazzo <daniele.varrazzo@gmail.com>
+
+# Use unittest2 if available. Otherwise mock a skip facility with warnings.
+
+try:
+    import unittest2
+    unittest = unittest2
+except ImportError:
+    import unittest
+    unittest2 = None
+
+if hasattr(unittest, 'skipIf'):
+    from unittest2 import skip, skipIf
+
+else:
+    import warnings
+
+    def skipIf(cond, msg):
+        def skipIf_(f):
+            def skipIf__(self):
+                if cond:
+                    warnings.warn(msg)
+                    return
+                else:
+                    return f(self)
+            return skipIf__
+        return skipIf_
+
+    def skip(msg):
+        return skipIf(True, msg)
+
+    def skipTest(self, msg):
+        warnings.warn(msg)
+        return
+
+    unittest.TestCase.skipTest = skipTest
+
+
+def decorate_all_tests(cls, decorator):
+    """Apply *decorator* to all the tests defined in the TestCase *cls*."""
+    for n in dir(cls):
+        if n.startswith('test'):
+            setattr(cls, n, decorator(getattr(cls, n)))
+            
diff --git a/tests/types_basic.py b/tests/types_basic.py
index aee4754..8e6f199 100755
--- a/tests/types_basic.py
+++ b/tests/types_basic.py
@@ -27,7 +27,7 @@ try:
 except:
     pass
 import sys
-import unittest
+from testutils import unittest
 
 import psycopg2
 import tests
@@ -78,14 +78,14 @@ class TypesBasicTests(unittest.TestCase):
             s = self.execute("SELECT %s AS foo", (decimal.Decimal("-infinity"),))
             self.failUnless(str(s) == "NaN", "wrong decimal quoting: " + str(s))
             self.failUnless(type(s) == decimal.Decimal, "wrong decimal conversion: " + repr(s))
+        else:
+            return self.skipTest("decimal not available")
 
     def testFloat(self):
         try:
             float("nan")
         except ValueError:
-            import warnings
-            warnings.warn("nan not available on this platform")
-            return
+            return self.skipTest("nan not available on this platform")
 
         s = self.execute("SELECT %s AS foo", (float("nan"),))
         self.failUnless(str(s) == "nan", "wrong float quoting: " + str(s))
diff --git a/tests/types_extras.py b/tests/types_extras.py
index dc5a585..062289e 100644
--- a/tests/types_extras.py
+++ b/tests/types_extras.py
@@ -20,14 +20,35 @@ except:
     pass
 import re
 import sys
-import unittest
-import warnings
+from testutils import unittest
 
 import psycopg2
 import psycopg2.extras
 import tests
 
 
+def skip_if_no_uuid(f):
+    def skip_if_no_uuid_(self):
+        try:
+            cur = self.conn.cursor()
+            cur.execute("select typname from pg_type where typname = 'uuid'")
+            has = cur.fetchone()
+        finally:
+            self.conn.rollback()
+
+        if has:
+            return f(self)
+        else:
+            return self.skipTest("uuid type not available")
+
+    return skip_if_no_uuid_
+
+def filter_scs(conn, s):
+    if conn.get_parameter_status("standard_conforming_strings") == 'off':
+        return s
+    else:
+        return s.replace("E'", "'")
+
 class TypesExtrasTests(unittest.TestCase):
     """Test that all type conversions are working."""
 
@@ -39,12 +60,10 @@ class TypesExtrasTests(unittest.TestCase):
         curs.execute(*args)
         return curs.fetchone()[0]
 
+    @skip_if_no_uuid
     def testUUID(self):
-        try:
-            import uuid
-            psycopg2.extras.register_uuid()
-        except:
-            return
+        import uuid
+        psycopg2.extras.register_uuid()
         u = uuid.UUID('9c6d5a77-7256-457e-9461-347b4358e350')
         s = self.execute("SELECT %s AS foo", (u,))
         self.failUnless(u == s)
@@ -52,12 +71,10 @@ class TypesExtrasTests(unittest.TestCase):
         s = self.execute("SELECT NULL::uuid AS foo")
         self.failUnless(s is None)
 
+    @skip_if_no_uuid
     def testUUIDARRAY(self):
-        try:
-            import uuid
-            psycopg2.extras.register_uuid()
-        except:
-            return
+        import uuid
+        psycopg2.extras.register_uuid()
         u = [uuid.UUID('9c6d5a77-7256-457e-9461-347b4358e350'), uuid.UUID('9c6d5a77-7256-457e-9461-347b4358e352')]
         s = self.execute("SELECT %s AS foo", (u,))
         self.failUnless(u == s)
@@ -86,13 +103,17 @@ class TypesExtrasTests(unittest.TestCase):
         i = Inet("192.168.1.0/24")
         a = psycopg2.extensions.adapt(i)
         a.prepare(self.conn)
-        self.assertEqual("E'192.168.1.0/24'::inet", a.getquoted())
+        self.assertEqual(
+            filter_scs(self.conn, "E'192.168.1.0/24'::inet"),
+            a.getquoted())
 
         # adapts ok with unicode too
         i = Inet(u"192.168.1.0/24")
         a = psycopg2.extensions.adapt(i)
         a.prepare(self.conn)
-        self.assertEqual("E'192.168.1.0/24'::inet", a.getquoted())
+        self.assertEqual(
+            filter_scs(self.conn, "E'192.168.1.0/24'::inet"),
+            a.getquoted())
 
     def test_adapt_fail(self):
         class Foo(object): pass
@@ -109,8 +130,7 @@ def skip_if_no_hstore(f):
         from psycopg2.extras import HstoreAdapter
         oids = HstoreAdapter.get_oids(self.conn)
         if oids is None:
-            warnings.warn("hstore not available in test database: skipping test")
-            return
+            return self.skipTest("hstore not available in test database")
         return f(self)
 
     return skip_if_no_hstore_
@@ -121,8 +141,7 @@ class HstoreTestCase(unittest.TestCase):
 
     def test_adapt_8(self):
         if self.conn.server_version >= 90000:
-            warnings.warn("skipping dict adaptation with PG pre-9 syntax")
-            return
+            return self.skipTest("skipping dict adaptation with PG pre-9 syntax")
 
         from psycopg2.extras import HstoreAdapter
 
@@ -136,16 +155,15 @@ class HstoreTestCase(unittest.TestCase):
         ii = q[1:-1].split("||")
         ii.sort()
 
-        self.assertEqual(ii[0], "(E'a' => E'1')")
-        self.assertEqual(ii[1], "(E'b' => E'''')")
-        self.assertEqual(ii[2], "(E'c' => NULL)")
+        self.assertEqual(ii[0], filter_scs(self.conn, "(E'a' => E'1')"))
+        self.assertEqual(ii[1], filter_scs(self.conn, "(E'b' => E'''')"))
+        self.assertEqual(ii[2], filter_scs(self.conn, "(E'c' => NULL)"))
         encc = u'\xe0'.encode(psycopg2.extensions.encodings[self.conn.encoding])
-        self.assertEqual(ii[3], "(E'd' => E'%s')" % encc)
+        self.assertEqual(ii[3], filter_scs(self.conn, "(E'd' => E'%s')" % encc))
 
     def test_adapt_9(self):
         if self.conn.server_version < 90000:
-            warnings.warn("skipping dict adaptation with PG 9 syntax")
-            return
+            return self.skipTest("skipping dict adaptation with PG 9 syntax")
 
         from psycopg2.extras import HstoreAdapter