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Test functions against spec

Generative testing with checkλ︎

clojure.spec.test.alpha/check generates 1000 values from the argument section of a function definition specification.

Pass the name of the function definition that has a specification to the check function.

(spec-test/check ``register-account-holder`)

Limiting the generated dataλ︎

1000 tests can take a noticeable time to run, so check is not as often used during active development, as it would slow down the normal fast feedback cycle with Clojure.

check takes an optional second argument which configures how the function operates. Passing a hash-map as a second argument will set the number of data values generated {:clojure.spec.test.check/opts {:num-tests 100}}

  {:clojure.spec.test.check/opts {:num-tests 100}})

Configuring check to run fewer tests provides a simple way to test multiple values without slowing down the development workflow.

Reporting on Generative testingλ︎

clojure.spec.test.alpha/summarize-results will return a brief summary including the total number of results and a count for how many results passed and failed.

  (spec-test/check `register-customer
                   {:clojure.spec.test.check/opts {:num-tests 10}}))

Use the threading macro to summarize the results of multiple check operations

(->> (spec-test/check `register-account-holder)
     (spec-test/check `open-current-bank-account)

If this expression is bound to a name then it can be called when ever the full suite of check generative testing is required.