Make tests.py create pipes in project root

tests.py

@@ -1,5 +1,6 @@
+# pylint: disable=redefined-outer-name
 from os import stat
-from os.path import exists
+from os.path import exists, dirname, realpath, join
 from stat import S_ISFIFO
 
 import pytest
@@ -9,7 +10,11 @@ from echo_server import EchoPipeIOServer
 
 @pytest.fixture
 def pipe_io():
-    pipe_server = EchoPipeIOServer()
+    here = dirname(realpath(__file__))
+    pipe_server = EchoPipeIOServer(
+        join(here, 'in_pipe_tests'),
+        join(here, 'out_pipe_tests')
+    )
     pipe_server.run()
     yield pipe_server
     pipe_server.stop()