Use uuid4() to generate BNode ids. Fixes issue #185

1 files changed, 8 insertions, 114 deletions

diff --git a/test/test_issue200.py b/test/test_issue200.py
index af1823ff..16386db7 100644
--- a/test/test_issue200.py
+++ b/test/test_issue200.py
@@ -1,146 +1,40 @@
 #!/usr/bin/env python
 
-import os, sys, time, random
+import os
 import rdflib
 import unittest
-try:
-    from hashlib import md5
-except ImportError:
-    from md5 import md5
-
 
 import platform
 if platform.system() == 'Java':
     from nose import SkipTest
     raise SkipTest('No os.pipe() in Jython, skipping')
 
-# Adapted from http://icodesnip.com/snippet/python/simple-universally-unique-id-uuid-or-guid
-def bnode_uuid():
-    """
-    Generates a uuid on behalf of Python 2.4
-    """
-    import socket
-    try: 
-        preseed = os.urandom(16)
-    except NotImplementedError: 
-        preseed = '' 
-    # Have doubts about this. random.seed will just hash the string 
-    random.seed('%s%s%s' % (preseed, os.getpid(), time.time())) 
-    del preseed 
-    t = long( time.time() * 1000.0 )
-    r = long( random.random()*100000000000000000L )
-    try:
-        a = socket.gethostbyname( socket.gethostname() )
-    except:
-        # if we can't get a network address, just imagine one
-        a = random.random()*100000000000000000L
-    data = str(t)+' '+str(r)+' '+str(a)
-    data = md5(data.encode('ascii')).hexdigest()
-    yield data
 
 class TestRandomSeedInFork(unittest.TestCase):
-    def test_same_bnodeid_sequence_in_fork(self):
-        """Demonstrates that os.fork()ed child processes produce the same 
-        sequence of BNode ids as the parent process.
-        """
-        r, w = os.pipe() # these are file descriptors, not file objects
-        pid = os.fork()
-        if pid:
-            pb1 = rdflib.term.BNode()
-            os.close(w) # use os.close() to close a file descriptor
-            r = os.fdopen(r) # turn r into a file object
-            txt = r.read()
-            os.waitpid(pid, 0) # make sure the child process gets cleaned up
-        else:
-            os.close(r)
-            w = os.fdopen(w, 'w')
-            cb = rdflib.term.BNode()
-            w.write(cb)
-            w.close()
-            os._exit(0)
-        assert txt == str(pb1), "Test now obsolete, random seed working"
 
-    def test_random_not_reseeded_in_fork(self):
-        """Demonstrates ineffectiveness of reseeding Python's random. 
+    def test_bnode_id_differs_in_fork(self):
+        """Checks that os.fork()ed child processes produce a
+        different sequence of BNode ids from the parent process.
         """
-        r, w = os.pipe() # these are file descriptors, not file objects
+        r, w = os.pipe()  # these are file descriptors, not file objects
         pid = os.fork()
         if pid:
             pb1 = rdflib.term.BNode()
-            os.close(w) # use os.close() to close a file descriptor
-            r = os.fdopen(r) # turn r into a file object
+            os.close(w)  # use os.close() to close a file descriptor
+            r = os.fdopen(r)  # turn r into a file object
             txt = r.read()
-            os.waitpid(pid, 0) # make sure the child process gets cleaned up
+            os.waitpid(pid, 0)  # make sure the child process gets cleaned up
         else:
             os.close(r)
-            try: 
-                preseed = os.urandom(16)
-            except NotImplementedError: 
-                preseed = '' 
-            # Have doubts about this. random.seed will just hash the string 
-            random.seed('%s%s%s' % (preseed, os.getpid(), time.time())) 
-            del preseed 
             w = os.fdopen(w, 'w')
             cb = rdflib.term.BNode()
             w.write(cb)
             w.close()
             os._exit(0)
-        assert txt == str(pb1), "Reseeding worked, this test is obsolete"
-
-    def test_bnode_uuid_differs_in_fork(self):
-        """
-        os.fork()ed child processes should produce a different sequence of 
-        BNode ids from the sequence produced by the parent process.
-        """
-        r, w = os.pipe() # these are file descriptors, not file objects
-        pid = os.fork()
-        if pid:
-            pb1 = rdflib.term.BNode(_sn_gen=bnode_uuid(), _prefix="urn:uuid:")
-            os.close(w) # use os.close() to close a file descriptor
-            r = os.fdopen(r) # turn r into a file object
-            txt = r.read()
-            os.waitpid(pid, 0) # make sure the child process gets cleaned up
-        else:
-            os.close(r)
-            w = os.fdopen(w, 'w')
-            cb = rdflib.term.BNode(_sn_gen=bnode_uuid(), _prefix="urn:uuid:")
-            w.write(cb)
-            w.close()
-            os._exit(0)
         assert txt != str(pb1), "Parent process BNode id: " + \
                                 "%s, child process BNode id: %s" % (
                                     txt, str(pb1))
 
-    def test_uuid_differs_in_fork(self):
-        """
-        os.fork()ed child processes using uuid4() should produce a different 
-        sequence of BNode ids from the sequence produced by the parent process.
-        """
-        if sys.version_info[:2] == (2, 4):
-            from nose import SkipTest
-            raise SkipTest('uuid4() not available prior to Python 2.5')
-        def bnode_uuid():
-            # Redefine 'cos Python 2.5 and above allows use of uuid
-            import uuid
-            yield uuid.uuid4()
-        r, w = os.pipe() # these are file descriptors, not file objects
-        pid = os.fork()
-        if pid:
-            pb1 = rdflib.term.BNode(_sn_gen=bnode_uuid(), _prefix="urn:uuid:")
-            os.close(w) # use os.close() to close a file descriptor
-            r = os.fdopen(r) # turn r into a file object
-            txt = r.read()
-            os.waitpid(pid, 0) # make sure the child process gets cleaned up
-        else:
-            os.close(r)
-            w = os.fdopen(w, 'w')
-            cb = rdflib.term.BNode(_sn_gen=bnode_uuid(), _prefix="urn:uuid:")
-            w.write(cb)
-            w.close()
-            os._exit(0)
-        assert txt != str(pb1), "Parent process BNode id: " + \
-                                "%s, child process BNode id: %s" % (
-                                    txt, str(pb1))
 
 if __name__ == "__main__":
     unittest.main()