Create a test case for the poll loop which uses the loop to read data from a

pipe and assert that the data written to the pipe is identical to the data
read from the pipe. In order to implement this test, several useful classes
have been added:

 * PipeReader

     Reads output from one or more files and saves it in memory,
     for retrieval via the getvalue() method. This is driven by
     the scheduler's poll() loop, so it runs entirely within the
     current process.

 * QueueScheduler

     Add instances of SequentialTaskQueue and then call run().
     The run() method returns when no tasks remain.

 * TaskScheduler

     A simple way to handle scheduling of AsynchrousTask instances. Simply
     add tasks and call run(). The run() method returns when no tasks remain.


svn path=/main/trunk/; revision=11022

3 files changed, 46 insertions, 0 deletions

diff --git a/pym/portage/tests/process/__init__.py b/pym/portage/tests/process/__init__.py
new file mode 100644
index 000000000..a4a87a461
--- /dev/null
+++ b/pym/portage/tests/process/__init__.py
@@ -0,0 +1,3 @@
+# Copyright 1998-2008 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Id: __init__.py 6870 2007-06-19 07:22:18Z zmedico $
diff --git a/pym/portage/tests/process/__test__ b/pym/portage/tests/process/__test__
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/pym/portage/tests/process/__test__
diff --git a/pym/portage/tests/process/test_poll.py b/pym/portage/tests/process/test_poll.py
new file mode 100644
index 000000000..45c0ad03e
--- /dev/null
+++ b/pym/portage/tests/process/test_poll.py
@@ -0,0 +1,43 @@
+# Copyright 1998-2008 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Id: test_spawn.py 8474 2007-11-09 03:35:38Z zmedico $
+
+import errno, os, sys
+from portage.tests import TestCase
+from _emerge import PipeReader, SpawnProcess, TaskScheduler
+
+class PollTestCase(TestCase):
+
+	def testPipeReader(self):
+		"""
+		Use a poll loop to read data from a pipe and assert that
+		the data written to the pipe is identical to the data
+		read from the pipe.
+		"""
+
+		test_string = 2 * "blah blah blah\n"
+
+		master_fd, slave_fd = os.pipe()
+ 		master_file = os.fdopen(master_fd, 'r')
+
+		task_scheduler = TaskScheduler(max_jobs=2)
+		scheduler = task_scheduler.sched_iface
+
+		producer = SpawnProcess(
+			args=["bash", "-c", "echo -n '%s'" % test_string],
+			fd_pipes={1:slave_fd}, scheduler=scheduler)
+
+		consumer = PipeReader(
+			input_files={"producer" : master_file},
+			scheduler=scheduler)
+
+		task_scheduler.add(producer)
+		task_scheduler.add(consumer)
+
+		def producer_start_cb(task):
+			os.close(slave_fd)
+
+		producer.addStartListener(producer_start_cb)
+		task_scheduler.run()
+
+		self.assertEqual(test_string, consumer.getvalue())