test.check generators and data completion for Schema
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A Clojure(Script) library for data generation and generative testing with https://github.com/plumatic/schema and clojure.test.check.

Clojars Project

This is an alpha release. The API and organizational structure are subject to change. Comments and contributions are much appreciated.


This library provides two experimental forms of automatic test data generation from schemas.

(require '[schema-generators.complete :as c] '[schema-generators.generators :as g])

(g/sample 3 Animal)
;; => ({:name "", :barks? false, :type :dog}
;;     {:name "", :claws? false, :type :cat}
;;     {:name "\"|", :claws? false, :type :cat})

(g/generate Tree)
;; => {:value -8N, :children [{:value 5, :children [{:value -2N, :children []}]}
;;                            {:value -2, :children []}]}

(c/complete {:type :dog} Animal)
;; => {:name "nL@", :barks? false, :type :dog}

The schema-generators.generators namespace can compile Schemas into clojure.test.check generators. All of the built-in schemas are supported out of the box, and it is easy to extend to add new types or customize generation on a per-type basis. See schema-generators.generators-test for some more complex examples.

Moreover, the schema-generators.complete namespace can build on generation to allow "completion" of partial data. Whereas generators and clojure.test.check are very useful tools for abstract property testing, completers are useful when we want to test the behavior of a function on a specific complex data structure, where only some parts of the data structure are relevant for the function under test. Completion supports all of the extensibility of generators, plus the ability to provide coercions to create very succinct helpers for test data generation. See schema-generators.complete-test for examples.



Please feel free to join the Plumbing mailing list to ask questions or discuss how you're using Schema.

We welcome contributions in the form of bug reports and pull requests; please see CONTRIBUTING.md in the repo root for guidelines.

Supported Clojure versions

Schema-generators are currently supported on Clojure 1.7 and 1.8 and the latest version of ClojureScript.


Distributed under the Eclipse Public License, the same as Clojure.