we need to cd to the final destination even if source fails

[bukzor]

This is a rough draft. I'll add test after you confirm the approach seems sound.

[chriskuehl]

otherwise lgtm

[chriskuehl]

this docstring seems false, this function does not "run a set of commands, stopping on the first error"

[bukzor]

When run in master, this test gives:

E           AssertionError: Incorrect output.
E           >>> Context:
E           TEST> 
E           >>> Expected:
E               pwd
E               /tmp/buck/pytest-of-buck/pytest-13/test_broken_activate_shell1_0/venv/child-dir
E               (activation failure)
E               
E           >>> Actual:
E               pwd
E               /tmp/buck/pytest-of-buck/pytest-13/test_broken_activate_shell1_0/venv
E               (activation failure)
E               TEST>

[bukzor]

Finally got around to it.