Optional `num-tests-or-opts` for `checking`

[DjebbZ]

Hello,

First of all thank @gfredericks for pointing me to the checking macro here https://groups.google.com/forum/#!topic/clojure/K7T8ZkF2VEU

The only small caveat is that while defspec make its options completely optional with a multi-arity macro, checking forces to specify the number of tests or a map. Maybe checking could reuse the same process-options function from test.check directly to be sure to reuse the same logic.

What do you think ?

[gfredericks]

that sounds fine to me!

[DjebbZ]

I quickly tried something but it failed:

(defmacro checking
  "A macro intended to replace the testing macro in clojure.test with a
  generative form. To make (testing \"doubling\" (is (= (* 2 2) (+ 2 2))))
  generative, you simply have to change it to
  (checking \"doubling\" 100 [x gen/int] (is (= (* 2 x) (+ x x)))).

  You can optionally pass in a map options instead of the number of tests,
  which will be passed to `clojure.test.check/quick-check`, e.g.:

    (checking \"doubling\" {:num-tests 100 :seed 123 :max-size 10}
      [x gen/int]
      (is (= (* 2 x) (+ x x))))

  For background, see
  http://blog.colinwilliams.name/blog/2015/01/26/alternative-clojure-dot-test-integration-with-test-dot-check/"
  ([name bindings & body] ;; NEW ARITY!
   `(checking ~name nil ~bindings ~body))
  ([name num-tests-or-options bindings & body]
   `(-testing ~name
              (fn []
                (let [final-reports# (atom [])
                      options# (tc.clojure-test/process-options ~num-tests-or-options)] ;; quickly copied from tc.clojure-test, my macro-fu is weak though
                  (qc-and-report-exception final-reports# options# ~bindings ~@body)
                  (doseq [r# @final-reports#]
                    (-report r#)))))))
;=> CompilerException java.lang.RuntimeException: Can't have more than 1 variadic overload

Since the macro takes a variable number of args, it's not possible to have different arities... I see no solution, do you?

[gfredericks]

you'd have to manually parse the arguments (e.g., macros like clojure.core/fn have to do this)

this is part of the problem that spec solves, but I'm not sure if adding spec to test.chuck is a good idea yet

to do it by hand, you would check if the second arg is a vector; if it's not, then you can assume it's the num-tests-or-options; if it is a vector, then the user must not have supplied one