;;; solar-tests.el --- tests for solar.el            -*- lexical-binding: t -*-

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(require 'ert)
(require 'solar)

(ert-deftest solar-sunrise-sunset ()
  ;; Bug#44237: wrong sunrise time on Dec 30 and 31, 2020 for Jaipur.
  (let ((calendar-latitude 26.9)
        (calendar-longitude 75.8)
        (calendar-time-zone +330)
        (calendar-standard-time-zone-name "IST")
        (calendar-daylight-time-zone-name "IST")
        (epsilon (/ 60.0)))             ; Minute accuracy is good enough.
    (let* ((sunrise-sunset (solar-sunrise-sunset '(12 30 2020)))
           (sunrise (car (nth 0 sunrise-sunset)))
           (sunset (car (nth 1 sunrise-sunset))))
      (should (< (abs (- sunrise 7.27)) epsilon))
      (should (< (abs (- sunset 17.72)) epsilon)))
    (let* ((sunrise-sunset (solar-sunrise-sunset '(12 31 2020)))
           (sunrise (car (nth 0 sunrise-sunset)))
           (sunset (car (nth 1 sunrise-sunset))))
      (should (< (abs (- sunrise 7.28)) epsilon))
      (should (< (abs (- sunset 17.72)) epsilon)))))

(provide 'solar-tests)