1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
;;; test-calendar-sync--nth-weekday-of-month.el --- Tests for calendar-sync--nth-weekday-of-month -*- lexical-binding: t; -*-
;;; Commentary:
;; Tests for the nth-weekday-of-month helper backing monthly/yearly BYDAY
;; expansion. Fixed dates are safe here: the function is pure calendar
;; arithmetic with no relation to the current time.
;;; Code:
(require 'ert)
(require 'calendar-sync)
;;; Normal Cases
(ert-deftest test-calendar-sync--nth-weekday-of-month-normal-second-wednesday ()
"Normal: 2nd Wednesday of Jan 2026 is the 14th."
;; Jan 2026: Jan 1 is a Thursday; Wednesdays fall on 7, 14, 21, 28.
(should (= (calendar-sync--nth-weekday-of-month 2026 1 3 2) 14)))
(ert-deftest test-calendar-sync--nth-weekday-of-month-normal-first-monday ()
"Normal: 1st Monday of Feb 2026 is the 2nd."
;; Feb 2026: Feb 1 is a Sunday; Mondays fall on 2, 9, 16, 23.
(should (= (calendar-sync--nth-weekday-of-month 2026 2 1 1) 2)))
(ert-deftest test-calendar-sync--nth-weekday-of-month-normal-last-tuesday ()
"Normal: last Tuesday of Mar 2026 is the 31st (negative ordinal)."
;; Mar 2026: Tuesdays fall on 3, 10, 17, 24, 31.
(should (= (calendar-sync--nth-weekday-of-month 2026 3 2 -1) 31)))
(ert-deftest test-calendar-sync--nth-weekday-of-month-normal-second-to-last-friday ()
"Normal: -2 ordinal picks the second-to-last Friday."
;; May 2026: Fridays fall on 1, 8, 15, 22, 29.
(should (= (calendar-sync--nth-weekday-of-month 2026 5 5 -2) 22)))
;;; Boundary Cases
(ert-deftest test-calendar-sync--nth-weekday-of-month-boundary-fifth-occurrence-exists ()
"Boundary: 5th Friday exists in May 2026."
(should (= (calendar-sync--nth-weekday-of-month 2026 5 5 5) 29)))
(ert-deftest test-calendar-sync--nth-weekday-of-month-boundary-fifth-occurrence-missing ()
"Boundary: 5th Wednesday of Feb 2026 does not exist -- returns nil."
;; Feb 2026 has four Wednesdays (4, 11, 18, 25).
(should (null (calendar-sync--nth-weekday-of-month 2026 2 3 5))))
(ert-deftest test-calendar-sync--nth-weekday-of-month-boundary-first-day-is-target ()
"Boundary: the 1st of the month itself is the 1st occurrence."
;; Apr 2026: Apr 1 is a Wednesday.
(should (= (calendar-sync--nth-weekday-of-month 2026 4 3 1) 1)))
(ert-deftest test-calendar-sync--nth-weekday-of-month-boundary-leap-february ()
"Boundary: leap-year February (2028) handled -- last Tuesday is the 29th."
;; Feb 2028: Feb 29 exists and is a Tuesday.
(should (= (calendar-sync--nth-weekday-of-month 2028 2 2 -1) 29)))
;;; Error Cases
(ert-deftest test-calendar-sync--nth-weekday-of-month-error-zero-ordinal-nil ()
"Error: ordinal 0 is meaningless -- returns nil."
(should (null (calendar-sync--nth-weekday-of-month 2026 1 3 0))))
(ert-deftest test-calendar-sync--nth-weekday-of-month-error-out-of-range-negative-nil ()
"Error: -6th occurrence never exists in a month -- returns nil."
(should (null (calendar-sync--nth-weekday-of-month 2026 1 3 -6))))
(provide 'test-calendar-sync--nth-weekday-of-month)
;;; test-calendar-sync--nth-weekday-of-month.el ends here
|
