From fda45105d60728df0659d1f8d5b9448383302fb1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dominik=20Pant=C5=AF=C4=8Dek?=
 <dominik.pantucek@trustica.cz>
Date: Sat, 11 Mar 2023 08:26:51 +0100
Subject: [PATCH] Month equality.

---
 brmsaptool.scm | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/brmsaptool.scm b/brmsaptool.scm
index 9f5038e..4675adb 100644
--- a/brmsaptool.scm
+++ b/brmsaptool.scm
@@ -141,8 +141,11 @@
 		 m))
       (error 'string->month "Invalid month" M)))
 
+;; Returns true if both arguments are a valid month and are equal
 (define (month=? m n)
-  #f)
+  (and (valid-month? m)
+       (valid-month? n)
+       (equal? m n)))
 
 (define (month<? m n)
   #f)
@@ -153,12 +156,16 @@
 
 (define (month-tests!)
   (display "[test] month ")
+  (unit-test 'month-valid? (month-valid? '(2023 5)))
+  (unit-test 'month-valid?-bad-year (not (month-valid? '(999 8))))
+  (unit-test 'month-valid?-bad-month (not (month-valid? '(2023 -5))))
   ;; Parsing
   (unit-test 'month->string (equal? (month->string '(2023 1)) "2023-01"))
   (unit-test 'month->string-bad-year (with-handler (lambda (x) #t) (month->string '(999 12)) #f))
   (unit-test 'month->string-bad-month (with-handler (lambda (x) #t) (month->string '(2023 13)) #f))
   ;; Comparison less
-  ;; Comparison equal
+  (unit-test 'month-equal? (month-equal? '(2023 4) '(2023 4)))
+  (unit-test 'month-equal? (not (month-equal? '(2023 4) '(2023 5))))
   ;; Comparison greater
   ;; Difference - TODO: inclusive both ends?
   (print " ok."))