Feedback on a base "fake" type in the testing repo

[Gustavo Niemeyer]

On Fri, Feb 13, 2015 at 2:05 PM, Eric Snow <eric.snow at canonical.com> wrote:
> As for me, by "fake" I mean a struct that implements an interface with
> essentially no logic other than to keep track of method calls and
> facilitate controlling their return values explicitly.  For examples
> see the implementations for GCE and in `testing/fake.go`.  Thus in
> tests a fake may be used in place of the concrete implementation of
> the interface that would be used in production.

To me this is a good fake implementation:

https://github.com/juju/juju/tree/master/provider/dummy

> The onus is on the test writer to populate the fake with the correct
> return values such that they would match the expected behavior of the
> concrete implementation.

That's an optimistic view of it, as I described.

> Regardless, I'm convinced that testing needs to include both high
> coverage via isolated unit tests and good enough coverage via "full
> stack" integration tests.  Essentially we have to ensure that layers
> work together properly and that low-level APIs work the way we expect
> (and don't change unexpectedly).

That's globally agreed. What's at stake is how to do these.


gustavo @ http://niemeyer.net