test: add a pouch version testcase

[sunyuan3]

Signed-off-by: Yuan Sun yile.sy@alibaba-inc.com

[pouchrobot]

Thanks for your contribution. 🍻 @sunyuan3
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More details, please refer to https://github.com/alibaba/pouch/blob/master/CONTRIBUTING.md

[allencloud]

Actually I like this integration test case.

While CI fails:

----------------------------------------------------------------------
FAIL: pouch_cli_version_test.go:23: PouchVersionSuite.TestPouchVersion
pouch_cli_version_test.go:25:
    c.Assert(err, check.IsNil)
... value *exec.Error = &exec.Error{Name:"pouch", Err:(*errors.errorString)(0xc42000e410)} ("exec: \"pouch\": executable file not found in $PATH")
OOPS: 2 passed, 1 FAILED
--- FAIL: Test (0.00s)
FAIL
FAIL	github.com/alibaba/pouch/test	0.004s

[allencloud]

I still be confused about how this suite works. Please next time you could share a little bit with us about how to add integration test via suite in Golang. 😄

[sunyuan3]

Ok. The way to add integration test case need to be added in document. I will add integration test demo in CI. Then I will create a document.

[allencloud]

LGTM