1 files changed, 61 insertions, 0 deletions
diff --git a/tests/unit/util/hnh-util-lens.scm b/tests/unit/util/hnh-util-lens.scm
new file mode 100644
index 00000000..0f4af6cb
--- /dev/null
+++ b/tests/unit/util/hnh-util-lens.scm
@@ -0,0 +1,61 @@
+(define-module (test hnh-util-lens)
+  :use-module (srfi srfi-64)
+  :use-module (srfi srfi-64 test-error)
+  :use-module (srfi srfi-88)
+  :use-module (hnh util lens))
+
+
+(define first (ref 0))
+
+(test-equal '((1)) (first '(((1)))))
+(test-equal '((2)) (set '(((1))) (compose-lenses first first) 2))
+(test-equal '(((2))) (set '(((1))) (compose-lenses first first first) 2))
+
+
+;; (list-change (iota 10) 5 'Hello)
+;; => (0 1 2 3 4 Hello 6 7 8 9)
+
+(test-equal '(1 (10) 3) (set '(1 (2) 3) (compose-lenses (ref 1) (ref 0)) 10))
+(test-equal '(1 (10) 3) (set '(1 (2) 3) (ref 1) (ref 0) 10))
+
+;; (set (list (iota 10)) first first 11)
+
+(define cadr* (compose-lenses cdr* car*))
+
+(test-group "Primitive lenses get and set"
+  (define lst '(1 2 3 4 5))
+  (test-equal 1 (car* lst))
+  (test-equal '(2 3 4 5) (cdr* lst))
+
+  (test-equal '(10 2 3 4 5)
+    (car* lst 10)))
+
+(test-group "Primitive lens composition"
+  (define lst '(1 2 3 4 5))
+  (test-equal 2 (cadr* lst))
+  (test-equal '(1 10 3 4 5) (cadr* lst 10)))
+
+(test-group "Modify"
+  (define lst '(1 2 3 4 5))
+  (test-equal '(10 2 3 4 5) (modify lst car* * 10))
+  (test-equal '(1 20 3 4 5) (modify lst cadr* * 10))
+  )
+
+(test-group "Modify*"
+  (define lst '(1 2 3 4 5))
+  (test-equal '(1 2 4 4 5) (modify* lst cdr* cdr* car* 1+)))
+
+;; modify
+;; modify*
+;; set
+;; get
+
+;; identity-lens
+;; compose-lenses
+;; lens-compose
+
+;; ref car* cdr*
+
+;; each
+
+'((hnh util lens))