adding first draft of tests for all examples, they need comments and clean up, some could be made more rebust

examples/test/test_popen.py

@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+
+"""TEST"""
+
+import unittest
+import pexpect
+from collections import defaultdict
+from mininet.log import setLogLevel
+
+class testPopen( unittest.TestCase ):
+    "Test ping with single switch topology (common code)."
+
+    def pingTest( self, name ):
+        p = pexpect.spawn( 'python -m %s' % name )
+        opts = []
+        opts.append( "<(h\d+)>: PING " )
+        opts.append( "<(h\d+)>: (\d+) packets transmitted, (\d+) received" )
+        opts.append( pexpect.EOF )
+        pings = {}
+        while True:
+            index = p.expect( opts )
+            if index == 0:
+                name = p.match.group(1)
+                pings[ name ] = 0
+            elif index == 1:
+                name = p.match.group(1)
+                transmitted = p.match.group(2)
+                received = p.match.group(3)
+                self.assertEqual( received, transmitted )
+                pings[ name ] += 1
+            else:
+                break
+        self.assertTrue( len(pings) > 0 )
+        for count in pings.values():
+            self.assertEqual( count, 1 )
+
+    def testPopen( self ):
+        self.pingTest( 'mininet.examples.popen' )
+
+    def testPopenPoll( self ):
+        self.pingTest( 'mininet.examples.popenpoll')
+
+if __name__ == '__main__':
+    setLogLevel( 'warning' )
+    unittest.main()