Support gen/gen (not serializable), fixes metosin#85

rschmukler · Nov 22, 2019 · c0ba26f · c0ba26f
1 parent 36c099f
commit c0ba26f
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Showing 3 changed files with 18 additions and 4 deletions.
diff --git a/README.md b/README.md
@@ -445,6 +445,14 @@ Scehmas can be used to generate values:
   [:and {:gen/fmap '(partial str "kikka_")} string?]
   {:seed 10, :size 10})
 ;; => "kikka_WT3K0yax2"
+
+(require '[clojure.test.check.generators :as gen])
+
+;; gen/gen (note, not serializable)
+(mg/generate
+  [:sequential {:gen/gen (gen/list gen/neg-int)} int?]
+  {:size 42, :seed 42})
+; => (-37 -13 -13 -24 -20 -11 -34 -40 -22 0 -10)
 ```
 
 Generated values are valid:

diff --git a/src/malli/generator.cljc b/src/malli/generator.cljc
@@ -80,8 +80,8 @@
 #?(:clj (defmethod -generator :re [schema opts] (-re-gen schema opts)))
 
 (defn- -create [schema opts]
-  (let [{:gen/keys [fmap elements]} (m/properties schema opts)
-        gen (when-not elements (-generator schema opts))
+  (let [{:gen/keys [gen fmap elements]} (m/properties schema opts)
+        gen (or gen (when-not elements (-generator schema opts)))
         elements (when elements (gen/elements elements))]
     (cond
       fmap (gen/fmap (m/eval fmap) (or elements gen (gen/return nil)))

diff --git a/test/malli/generator_test.cljc b/test/malli/generator_test.cljc
@@ -1,5 +1,6 @@
 (ns malli.generator-test
   (:require [clojure.test :refer [deftest testing is]]
+            [clojure.test.check.generators :as gen]
             [malli.json-schema-test :as json-schema-test]
             [malli.generator :as mg]
             [malli.core :as m]))
@@ -27,7 +28,7 @@
             (let [re #"^\d+ \d+$"]
               (m/validate re (mg/generate re)))
 
-            (let [re-test #"(?=.{8,})"                      ;; contains unsupported feature
+            (let [re-test #"(?=.{8,})" ;; contains unsupported feature
                   elements ["abcdefgh" "01234567"]
                   fmap '(fn [s] (str "prefix_" s))]
               (is (thrown-with-msg? Exception #"Unsupported-feature" (mg/generator [:re re-test])))
@@ -52,4 +53,9 @@
     (dotimes [_ 1000]
       (#{1 2} (mg/generate [:and {:gen/elements [1 2]} int?])))
     (dotimes [_ 1000]
-      (#{"1" "2"} (mg/generate [:and {:gen/elements [1 2], :gen/fmap 'str} int?])))))
+      (#{"1" "2"} (mg/generate [:and {:gen/elements [1 2], :gen/fmap 'str} int?]))))
+  (testing "gen/gen"
+    (dotimes [_ 1000]
+      (#{1 2} (mg/generate [:and {:gen/gen (gen/elements [1 2])} int?])))
+    (dotimes [_ 1000]
+      (#{"1" "2"} (mg/generate [:and {:gen/gen (gen/elements [1 2]) :gen/fmap str} int?])))))