After commit c018f5fd29 Fenrir is being switched over to go. If you do not want to be part of the testing process, please switch to master.

internal/datetime/datetime_test.go

@@ -0,0 +1,53 @@
+// Copyright (c) 2026 Storm Dragon
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package datetime
+
+import (
+	"testing"
+	"time"
+)
+
+func TestFormatsAndExamples(t *testing.T) {
+	now := time.Date(2026, 10, 25, 14, 5, 9, 0, time.FixedZone("fixture", -4*3600))
+	for _, testCase := range []struct {
+		id, want string
+		date     bool
+	}{
+		{"24-hour", "14:05", false},
+		{"24-hour-seconds", "14:05:09", false},
+		{"24-hour-words", "14 hours and 05 minutes", false},
+		{"24-hour-seconds-words", "14 hours, 05 minutes and 09 seconds", false},
+		{"numbers-dm", "25/10", true},
+		{"numbers-md", "10/25", true},
+		{"numbers-dmy", "25/10/2026", true},
+		{"numbers-mdy", "10/25/2026", true},
+		{"numbers-ymd", "2026/10/25", true},
+	} {
+		format := Format_time
+		if testCase.date {
+			format = Format_date
+		}
+		if got, ok := format(testCase.id, now); !ok || got != testCase.want {
+			t.Fatal(testCase.id, got, ok)
+		}
+	}
+	for _, date := range []bool{false, true} {
+		options, format, valid := Time_options(now), Format_time, Valid_time
+		if date {
+			options, format, valid = Date_options(now), Format_date, Valid_date
+		}
+		for _, option := range options {
+			got, ok := format(option.Value, now)
+			if !ok || !valid(option.Value) || got == "" || got != option.Label {
+				t.Fatal(option, got, ok)
+			}
+		}
+		if got, ok := format("%arbitrary", now); ok || got != "" || valid("%arbitrary") {
+			t.Fatal("invalid preset accepted")
+		}
+	}
+	if got, _ := Format_time("24-hour-seconds", now.Add(10*time.Hour)); got != "00:05:09" {
+		t.Fatal(got)
+	}
+}