Add test that should fail

FIXME: It doesn't, find out why!

When this test passes we should be able to trace pipes on Linux.

px/px_ipc_map_test.py

@@ -5,16 +5,17 @@
 import testutils
 
 
-def create_file(type, name, device, pid, access=None):
+def create_file(type, name, device, pid, access=None, inode=None):
     file = px_file.PxFile()
     file.type = type
 
     # Remove leading [] group from name if any
     file.name = re.match('(\[[^]]*\] )?(.*)', name).group(2)
 
     file.pid = pid
-    file.access = access
     file.device = device
+    file.access = access
+    file.inode = inode
     return file
 
 
@@ -60,6 +61,15 @@ def test_get_other_end_pids_osx_pipe2():
     assert found == set([25, 26])
 
 
+def test_get_other_end_pids_linux_pipe():
+    files = [
+        create_file("FIFO", "pipe", None, 100, inode="100200", access="r"),
+        create_file("FIFO", "pipe", None, 200, inode="100200", access="w"),
+    ]
+    assert get_other_end_pids(files[0], files) == set([200])
+    assert get_other_end_pids(files[1], files) == set([100])
+
+
 def test_get_other_end_pids_fifo1():
     files = [create_file("FIFO", "[] /fifo/name", None, 25, "r")]