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Generative test runner.

Releases and Dependency Information

Latest stable release: 1.0.0

CLI/deps.edn dependency information:

org.clojure/test.generative {:mvn/version "1.0.0"}

Leiningen dependency information:

[org.clojure/test.generative "1.0.0"]

Maven dependency information:


Example Usages

A defspec consists of a name, a function to be tested, an input spec, and a validator:

(defspec integers-closed-over-addition
  (fn [a b] (+' a b))                    ;; input fn
  [^long a ^long b]                     ;; input spec
  (assert (integer? %)))                ;; 0 or more validator forms

To generate test data, see the fns in the generators namespace. Note that these functions shadow a bunch of clojure.core names.

You can also create the underlying test data structures directly, marking vars with :clojure.test.generative/specs so they are picked up by the runner. This can be useful e.g. to model relationships between input parameters, or to specify a finite list of special cases. The example below specifies five specific one-argument arg lists:

(def ^::tgen/specs
  [{:test 'clojure.test.math-test/inc'-doesnt-overflow
    :input-gen #(map vector [Long/MIN_VALUE -1 0 1 Long/MAX_VALUE])}])

Running Interactively During Development

Specify the number of threads, the number of msec, and one or more vars to test:

(runner/run 2 1000 #'my/test-var)

Running in a CI environment

Wire your runner to call runner/-main with a list of directories where tests can be found. You can see bin/test.clj for an example.

You can use the following system properties to control the intensity of your test

Java PropertyInterpretation
clojure.test.generative.threadsNumber of concurrent threads
clojure.test.generative.msecDesired test run duration

Developer Information

Related Projects

  • ClojureCheck adds property based testing to clojure.test following the lines of QuickCheck for Haskell.
  • simple-check is a Clojure property-based testing tool inspired by QuickCheck.

Copyright and License

Copyright (c) 2012-2020 Rich Hickey. All rights reserved. The use and distribution terms for this software are covered by the Eclipse Public License 1.0 ( which can be found in the file epl-v10.html at the root of this distribution. By using this software in any fashion, you are agreeing to be bound bythe terms of this license. You must not remove this notice, or any other, from this software.


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