make test: improve robustness and performance

Introduce an API which asserts empty capture for interface.
Throw exception in old API if the capture does not exist, thus
making it clear if the test expects packets to arrive or not.
Improve performance by not doing sleeps after starting the packet
generator, rather lazily deleting captures when needed.
Fix wrong usage of packet.show() in various tests.

Change-Id: I456cb23316eef99b3f35f80344fe595c4db9a21c
Signed-off-by: Klement Sekera <ksekera@cisco.com>

1 files changed, 12 insertions, 19 deletions

diff --git a/test/test_l2xc_multi_instance.py b/test/test_l2xc_multi_instance.py
index 4de76917..2e55674e 100644
--- a/test/test_l2xc_multi_instance.py
+++ b/test/test_l2xc_multi_instance.py
@@ -56,7 +56,7 @@ from scapy.layers.l2 import Ether
 from scapy.layers.inet import IP, UDP
 
 from framework import VppTestCase, VppTestRunner
-from util import Host
+from util import Host, ppp
 
 
 class TestL2xcMultiInst(VppTestCase):
@@ -79,7 +79,7 @@ class TestL2xcMultiInst(VppTestCase):
             cls.flows = dict()
             for i in range(len(cls.pg_interfaces)):
                 delta = 1 if i % 2 == 0 else -1
-                cls.flows[cls.pg_interfaces[i]] = [cls.pg_interfaces[i+delta]]
+                cls.flows[cls.pg_interfaces[i]] = [cls.pg_interfaces[i + delta]]
 
             # Mapping between packet-generator index and lists of test hosts
             cls.hosts_by_pg_idx = dict()
@@ -155,9 +155,9 @@ class TestL2xcMultiInst(VppTestCase):
         (Default value = 0)
         """
         for i in range(count):
-            rx_if = self.pg_interfaces[i+start]
+            rx_if = self.pg_interfaces[i + start]
             delta = 1 if i % 2 == 0 else -1
-            tx_if = self.pg_interfaces[i+start+delta]
+            tx_if = self.pg_interfaces[i + start + delta]
             self.vapi.sw_interface_set_l2_xconnect(rx_if.sw_if_index,
                                                    tx_if.sw_if_index, 1)
             self.logger.info("Cross-connect from %s to %s created"
@@ -177,9 +177,9 @@ class TestL2xcMultiInst(VppTestCase):
         (Default value = 0)
         """
         for i in range(count):
-            rx_if = self.pg_interfaces[i+start]
+            rx_if = self.pg_interfaces[i + start]
             delta = 1 if i % 2 == 0 else -1
-            tx_if = self.pg_interfaces[i+start+delta]
+            tx_if = self.pg_interfaces[i + start + delta]
             self.vapi.sw_interface_set_l2_xconnect(rx_if.sw_if_index,
                                                    tx_if.sw_if_index, 0)
             self.logger.info("Cross-connect from %s to %s deleted"
@@ -253,8 +253,7 @@ class TestL2xcMultiInst(VppTestCase):
                 self.assertEqual(udp.sport, saved_packet[UDP].sport)
                 self.assertEqual(udp.dport, saved_packet[UDP].dport)
             except:
-                self.logger.error("Unexpected or invalid packet:")
-                self.logger.error(packet.show())
+                self.logger.error(ppp("Unexpected or invalid packet:", packet))
                 raise
         for i in self.pg_interfaces:
             remaining_packet = self.get_next_packet_info_for_interface2(
@@ -291,21 +290,15 @@ class TestL2xcMultiInst(VppTestCase):
         # Verify
         # Verify outgoing packet streams per packet-generator interface
         for pg_if in self.pg_interfaces:
-            capture = pg_if.get_capture()
             if pg_if in self.pg_in_xc:
-                if len(capture) == 0:
-                    raise RuntimeError("Interface %s is cross-connect sink but "
-                                       "the capture is empty!" % pg_if.name)
+                capture = pg_if.get_capture(
+                    remark="interface is a cross-connect sink")
                 self.verify_capture(pg_if, capture)
             elif pg_if in self.pg_not_in_xc:
-                try:
-                    self.assertEqual(len(capture), 0)
-                except AssertionError:
-                    raise RuntimeError("Interface %s is not cross-connect sink "
-                                       "but the capture is not empty!"
-                                       % pg_if.name)
+                pg_if.assert_nothing_captured(
+                    remark="interface is not a cross-connect sink")
             else:
-                self.logger.error("Unknown interface: %s" % pg_if.name)
+                raise Exception("Unexpected interface: %s" % pg_if.name)
 
     def test_l2xc_inst_01(self):
         """ L2XC Multi-instance test 1 - create 10 cross-connects