Test panic in to_rfc3339

Author: pitdicker

src/datetime/tests.rs

@@ -606,6 +606,7 @@ fn test_rfc_2822_year_range_panic_low() {
 
 #[test]
 #[cfg(feature = "alloc")]
+#[allow(deprecated)]
 fn test_datetime_rfc3339() {
     let edt5 = FixedOffset::east_opt(5 * 60 * 60).unwrap();
     let edt0 = FixedOffset::east_opt(0).unwrap();
@@ -691,6 +692,31 @@ fn test_datetime_rfc3339() {
     assert!(DateTime::parse_from_rfc3339(" 2015-02-18T23:59:60.234567+05:00").is_err());
     assert!(DateTime::parse_from_rfc3339("2015- 02-18T23:59:60.234567+05:00").is_err());
     assert!(DateTime::parse_from_rfc3339("2015-02-18T23:59:60.234567A+05:00").is_err());
+
+    const RFC_3339_YEAR_MAX: i32 = 9999;
+    const RFC_3339_YEAR_MIN: i32 = 0;
+
+    let dt = Utc.with_ymd_and_hms(RFC_3339_YEAR_MAX, 1, 2, 3, 4, 5).unwrap();
+    assert_eq!(dt.to_rfc3339(), "9999-01-02T03:04:05+00:00");
+
+    let dt = Utc.with_ymd_and_hms(RFC_3339_YEAR_MIN, 1, 2, 3, 4, 5).unwrap();
+    assert_eq!(dt.to_rfc3339(), "0000-01-02T03:04:05+00:00");
+}
+
+#[test]
+#[should_panic]
+#[cfg(feature = "alloc")]
+#[allow(deprecated)]
+fn test_rfc_3339_year_range_panic_high() {
+    let _ = Utc.with_ymd_and_hms(10000, 1, 2, 3, 4, 5).unwrap().to_rfc3339();
+}
+
+#[test]
+#[should_panic]
+#[cfg(feature = "alloc")]
+#[allow(deprecated)]
+fn test_rfc_3339_year_range_panic_low() {
+    let _ = Utc.with_ymd_and_hms(-1, 1, 2, 3, 4, 5).unwrap().to_rfc3339();
 }
 
 #[test]