Investigate novel pub/sub system test failure (only one message returned) #1081
Description
From: https://travis-ci.org/GoogleCloudPlatform/gcloud-python/builds/77052107
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ERROR: test_message_pull_mode_e2e (pubsub.TestPubsub)
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Traceback (most recent call last):
File "/home/travis/build/GoogleCloudPlatform/gcloud-python/system_tests/pubsub.py", line 129, in test_message_pull_mode_e2e
message1, message2 = sorted(messages, key=_by_timestamp)
ValueError: need more than 1 value to unpack
----------------------------------------------------------------------FWIW It seems pretty straightforward. Maybe we should revive #535? Our system tests are very flaky now.