From 358377db972caa25ba3369a5074e10c4775c2197 Mon Sep 17 00:00:00 2001
From: JackFirth <jackhfirth@gmail.com>
Date: Sun, 22 Feb 2015 18:51:12 -0800
Subject: [PATCH] Add list lens tests

---
 lenses/list.rkt | 47 ++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 40 insertions(+), 7 deletions(-)

diff --git a/lenses/list.rkt b/lenses/list.rkt
index d43e0fa..cf11612 100644
--- a/lenses/list.rkt
+++ b/lenses/list.rkt
@@ -1,5 +1,8 @@
 #lang racket
 
+(require rackunit
+         "core.rkt")
+
 (provide list-lens
          first-lens
          second-lens
@@ -29,6 +32,30 @@
 (define fourth-lens (list-lens 3))
 (define fifth-lens (list-lens 4))
 
+(module+ test
+  (check-eqv? (lens-view first-lens '(1 2 3 4 5)) 1)
+  (check-eqv? (lens-view second-lens '(1 2 3 4 5)) 2)
+  (check-eqv? (lens-view third-lens '(1 2 3 4 5)) 3)
+  (check-eqv? (lens-view fourth-lens '(1 2 3 4 5)) 4)
+  (check-eqv? (lens-view fifth-lens '(1 2 3 4 5)) 5)
+  (check-equal? (lens-set first-lens '(1 2 3 4 5) 'a) '(a 2 3 4 5))
+  (check-equal? (lens-set second-lens '(1 2 3 4 5) 'a) '(1 a 3 4 5))
+  (check-equal? (lens-set third-lens '(1 2 3 4 5) 'a) '(1 2 a 4 5))
+  (check-equal? (lens-set fourth-lens '(1 2 3 4 5) 'a) '(1 2 3 a 5))
+  (check-equal? (lens-set fifth-lens '(1 2 3 4 5) 'a) '(1 2 3 4 a)))
+
+(define (assoc-swap assoc-list old-assoc-pair new-assoc-pair #:is-equal? [equal? equal?])
+  (define (swap-assoc-pair assoc-pair)
+    (if (equal? assoc-pair old-assoc-pair)
+        new-assoc-pair
+        assoc-pair))
+  (map swap-assoc-pair assoc-list))
+
+(module+ test
+  (define assoc-list '((a 1) (b 2) (c 3)))
+  (check-equal? (assoc-swap assoc-list '(b 2) '(FOO BAR))
+                '((a 1) (FOO BAR) (c 3))))
+
 (define ((assoc-lens assoc-key #:is-equal? [equal? equal?]) assoc-list)
   (define assoc-pair (assoc assoc-key assoc-list equal?))
   (define (assoc-set new-assoc-pair)
@@ -37,12 +64,11 @@
         (append assoc-list new-assoc-pair)))
   (values assoc-pair assoc-set))
 
-(define (assoc-swap assoc-list old-assoc-pair new-assoc-pair #:is-equal? [equal? equal?])
-  (define (swap-assoc-pair assoc-pair)
-    (if (equal? assoc-pair old-assoc-pair)
-        new-assoc-pair
-        assoc-pair))
-  (map swap-assoc-pair assoc-list))
+(module+ test
+  (define assoc-a-lens (assoc-lens 'a))
+  (check-equal? (lens-view assoc-a-lens assoc-list) '(a 1))
+  (check-equal? (lens-set assoc-a-lens assoc-list '(FOO BAR))
+                '((FOO BAR) (b 2) (c 3))))
 
 (define (assv-lens assv-key)
   (assoc-lens assv-key #:is-equal? eqv?))
@@ -56,4 +82,11 @@
     (if assf-pair
         (assoc-swap assoc-list assf-pair new-assf-pair #:is-equal? eq?)
         (append assoc-list new-assf-pair)))
-  (values assf-pair assf-set))
\ No newline at end of file
+  (values assf-pair assf-set))
+
+(module+ test
+  (define assf>10-lens (assf-lens (λ (v) (> v 10))))
+  (define assf-list '((1 a) (10 b) (100 c)))
+  (check-equal? (lens-view assf>10-lens assf-list) '(100 c))
+  (check-equal? (lens-set assf>10-lens assf-list '(FOO BAR))
+                '((1 a) (10 b) (FOO BAR))))
\ No newline at end of file