case-insensitive-string-generator

project.clj

@@ -1,10 +1,10 @@
-(defproject com.velisco/strgen "0.1.9"
+(defproject com.velisco/strgen "0.2.0"
   :description "String generator from regular expressions, for use with Clojure test.check and spec"
   :url "https://github.com/miner/strgen"
   :deploy-repositories {"releases" :clojars}
   :license {:name "Eclipse Public License"
             :url "http://www.eclipse.org/legal/epl-v10.html"}
-  :dependencies [[org.clojure/clojure "1.9.0"]
-                 [org.clojure/clojurescript "1.10.439"]
-                 [org.clojure/test.check "1.0.0"]])
+  :dependencies [[org.clojure/clojure "1.10.3"]
+                 [org.clojure/clojurescript "1.10.844"]
+                 [org.clojure/test.check "1.1.0"]])
 

src/miner/strgen.cljc

@@ -1,9 +1,10 @@
 (ns miner.strgen
-  (:require [miner.strgen.impl :as impl]))
+  (:require [miner.strgen.impl :as impl]
+            [clojure.test.check.generators :as gen]))
 
 (defn string-generator
   "Returns a test.check generator that generates strings matching the given regular
-  expression `regex`.  (Fancy flags and POXIX extensions are not suppored; see the doc for
+  expression `regex`.  (Fancy flags and POSIX extensions are not suppored; see the doc for
   more information about the supported regular expression syntax.)  The optional
   `or-more-limit` controls the maximum numbers of elements that are generated when matching
   a potentially unbounded regex (such as #\"x*\" or #\"y+\").  The default is 9."
@@ -14,3 +15,13 @@
   ([regex or-more-limit]
    (impl/string-generator regex or-more-limit)))
 
+
+(defn case-insensitive-string-generator
+  "Like `string-generator` but case-insensitive so it generates a mix of upper and lowercase
+  characters for the given regex."
+
+  ([regex]
+   (gen/bind (string-generator regex) impl/gen-case-insensitive))
+
+  ([regex or-more-limit]
+   (gen/bind (string-generator regex or-more-limit) impl/gen-case-insensitive)))

src/miner/strgen/impl.cljc

@@ -1,5 +1,6 @@
 (ns miner.strgen.impl
   (:require [clojure.set :as set]
+            [clojure.string :as str]
             #?(:cljs cljs.reader)
             [clojure.test.check.generators :as gen]))
 
@@ -271,7 +272,7 @@
         :else (throw (ex-info (str "Unimplemented generator for " (pr-str tree))
                               {:unimplemented tree}))))
 
-;; this is the only function needed for the public side
+;; this is the main function needed for the public side
 (defn string-generator
   "Returns a test.check generator that generates strings matching the given regular
   expression `regex`.  (Fancy flags and POXIX extensions are not suppored; see the doc for
@@ -286,3 +287,12 @@
   ([regex or-more-limit]
    (binding [*or-more-limit* or-more-limit]
      (string-generator regex))))
+
+;; also used for the public side, to implement case-insensitive generation
+(defn gen-case-insensitive [s]
+  (let [ups (str/upper-case s)
+        lows (str/lower-case s)]
+    (gen/one-of [(gen/elements [s (str/capitalize s) ups lows])
+                 (gen/fmap (fn [bs]
+                             (str/join (map (fn [b low up] (if b up low)) bs lows ups)))
+                           (gen/vector gen/boolean (count s)))])))

test/miner/test_strgen.cljc

@@ -4,6 +4,7 @@
       :clj  [clojure.test :refer [deftest is]])
             [clojure.test.check.generators :as gen]
             [clojure.spec.alpha :as s]
+            [clojure.string :as str]
             [miner.strgen :as sg]))
 
 ;; https://github.com/bensu/doo -- need a test runner for CLJS
@@ -58,3 +59,19 @@
   (doseq [re regexes]
     (test-spec-re re)))
 
+
+;; SEM FIXME: Not a complete test as we convert everything back to lowercase before
+;; matching.  Could break if we changed `regexs` to require uppercase.  We should also
+;; validate that the generator yields sensible mixed case results.
+(defn test-spec-re-case-insensitive
+  ([re] (test-re re *exercise-limit*))
+  ([re limit]
+   (doseq [[r c] (s/exercise (s/spec (s/and string? #(re-matches re (str/lower-case %)))
+                                     :gen #(sg/case-insensitive-string-generator re))
+                             limit)]
+     (is (= r c)))))
+
+(deftest spec-regexes-case-insensitive
+  (doseq [re regexes]
+    (test-spec-re-case-insensitive re)))
+