Add new tests.

1 files changed, 87 insertions, 0 deletions

diff --git a/tests/test/tz.scm b/tests/test/tz.scm
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+++ b/tests/test/tz.scm
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+;;; Commentary:
+;; Tests that datetime->unix-time correctly converts between Olssen
+;; timezone definitions (e.g. Europe/Stockholm), into correct times
+;; and offsets (in unix time).
+;; Also indirectly tests the Zone Info Compiler (datetime zic), since
+;; the zoneinfo comes from there.
+;;; Code:
+
+(define-module (test tz)
+  :use-module (srfi srfi-64)
+  :use-module (srfi srfi-88)
+  :use-module ((datetime)
+               :select (parse-ics-datetime
+                        datetime
+                        date
+                        time
+                        datetime->unix-time
+                        unix-time->datetime
+                        get-datetime))
+  :use-module ((hnh util) :select (let-env)))
+
+;; London alternates between +0000 and +0100
+(let-env
+  ((TZ "Europe/London"))
+  (test-equal
+    "London winter"
+    #2020-01-12T13:30:00
+    (get-datetime
+      (parse-ics-datetime "20200112T133000Z")))
+  (test-equal
+    "London summer"
+    #2020-06-12T14:30:00
+    (get-datetime
+      (parse-ics-datetime "20200612T133000Z"))))
+
+;; Stockholm alternates between +0100 and +0200
+(let-env
+  ((TZ "Europe/Stockholm"))
+  (test-equal
+    "Stockholm winter"
+    #2020-01-12T14:30:00
+    (get-datetime
+      (parse-ics-datetime "20200112T133000Z")))
+  (test-equal
+    "Stockholm summer"
+    #2020-06-12T15:30:00
+    (get-datetime
+      (parse-ics-datetime "20200612T133000Z"))))
+
+(test-equal
+  -10800
+  (datetime->unix-time
+    (parse-ics-datetime
+      "19700101T000000"
+      "Europe/Tallinn")))
+
+(test-equal
+  -3600
+  (datetime->unix-time
+    (parse-ics-datetime
+      "19700101T000000"
+      "Europe/Stockholm")))
+
+(test-equal
+  0
+  (datetime->unix-time
+    (parse-ics-datetime "19700101T000000Z")))
+
+;; yes, really
+(test-equal
+  -3600
+  (datetime->unix-time
+    (parse-ics-datetime
+      "19700101T000000"
+      "Europe/London")))
+
+(test-equal
+  (datetime
+    date:
+    #1970-01-01
+    time:
+    #00:00:00
+    tz:
+    "UTC")
+  (unix-time->datetime 0))
+
+