twisted.conch.test.test_cftp.TestOurServerCmdLineClient.testCommand fails when run as a user without a shell

New submission from exarkun <[email protected]>:

This test runs `cftp` as a child process and then issues a shell escape command to it.  However, as the user running the process has no shell, the command cannot be evaluated.  The test should provide a fake ''which user am I, and what is my shell'' implementation and exercise the usual case through this code path as well as the missing shell case (perhaps adding that can be split off into a separate ticket).

This test is failing on several builders which are now running on accounts without shells.


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Type     : defect
Component: conch
Keywords : 
Priority : high
Nosy     : 
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http://twistedmatrix.com/trac/ticket/3914