clojure.test parameterized tests

[Brian Craft]

I have a number of tests that I would like to run against different implementations of a protocol. In clojure.test there doesn't appear to be a way to parameterize a test over the implementations. Is there a good way to do this?

[Chris Price]

I have been curious about this too.  I was playing around with it a few weeks ago and came up with this:

https://github.com/cprice404/clj-shared-test-sandbox/blob/master/test/shared_tests_foo/core_test.clj

Which is pretty gross; it uses `binding` + a dynamic var in the shared test namespace, and then it calls `clojure.test/run-tests` from inside of a `deftest`.  I'm sure there's got to be a better way, but that was as far as I got in the small amount of time that I was able to spend on it.

[Brian Craft]

Thanks. I did something similar. I have different implementations per db, so use a global *db* var:

(ct/deftest run-tests

  (matrix1)) ; matrix1 tests against *db*

(ct/deftest test-h2

  (binding [*db* (h2/create-db2 "test" {:subprotocol "h2:mem"})]

    (run-tests)))

(defn test-ns-hook []

  (test-h2))

Clumsy, but seems to be the only option.

[Karsten Schmidt]

You can use the `testing` macro and wrap it in a function, which accepts your type/protocol implementation or even individual protocol methods as args. Example here:

https://github.com/thi-ng/geom/blob/master/test/core.org#callable-contexts

--
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to clo...@googlegroups.com
Note that posts from new members are moderated - please be patient with your first post.
To unsubscribe from this group, send email to
clojure+u...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
---
You received this message because you are subscribed to the Google Groups "Clojure" group.
To unsubscribe from this group and stop receiving emails from it, send an email to clojure+u...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Brian Craft]

Wow, I never would have figured that out from the docs. Thanks.

Just found a different problem with my solution: nested tests, as described in the docs, prevent the use of fixtures. You have to add test-ns-hook when using nested tests, and then fixtures aren't run.

[Reid Draper]

Keep in mind too that since test.check/quick-check takes a property as an argument, you can construct a property by simply closing over some implementation. For example:

(defn make-prop

  [impl]

  (prop/for-all [...]

    (= (impl ...) (other ...)))

And then test with different properties created with (make-prop ...).

Reid

[Brian Craft]

Using the "testing" macro introduces the same problem with fixtures. Fixtures don't run except around things defined with deftest.

Anyone have an example of a test 1) parameterized, and 2) with working fixture?

Someone suggested the Expectations lib, but I don't see any fixture support there. Anyone using Expectations that can point me to the right place?

[Sean Corfield]

http://jayfields.com/expectations/in-context.html