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#![allow(clippy::all, clippy::pedantic, clippy::restriction, warnings)]
#[cfg(all(feature = "jiff-tz", feature = "parse"))]
mod tests {
use deep_time::{Dt, ParseCfg, Scale};
use jiff::{Timestamp, Zoned, civil::DateTime};
#[test]
fn test_historical_iana_with_jiff() {
let cases = vec![
(
"2020-06-15 14:30:00",
"America/New_York",
"NY summer (EDT = UTC-4)",
),
(
"2020-12-15 14:30:00",
"America/New_York",
"NY winter (EST = UTC-5)",
),
(
"2023-11-05 01:30:00",
"America/New_York",
"NY DST fall-back (ambiguous hour - overlap)",
),
(
"2023-03-12 02:30:00",
"America/New_York",
"NY DST spring-forward (gap)",
),
(
"2024-03-10 02:30:00",
"America/New_York",
"Recent spring-forward gap",
),
(
"2024-11-03 01:30:00",
"America/New_York",
"Recent fall-back overlap",
),
("1999-12-31 23:59:59", "Europe/London", "London historical"),
(
"1969-07-20 20:17:00",
"America/New_York",
"Moon landing (very old TZ rules)",
),
(
"1955-01-01 00:00:00",
"Europe/London",
"Mid-20th century rules (pre-modern DST)",
),
("1970-01-01 00:00:00", "UTC", "UTC edge case"),
(
"2024-06-15 14:30:00",
"Asia/Kolkata",
"Half-hour offset (India UTC+5:30 - no DST)",
),
(
"2024-02-15 12:00:00",
"Australia/Sydney",
"Southern hemisphere DST (spring-forward in Oct)",
),
(
"2024-12-15 14:30:00",
"Pacific/Chatham",
"Unusual 45-minute offset (Chatham Islands)",
),
(
"2035-07-01 12:00:00",
"America/New_York",
"Far future date (repeating tail / far-future logic)",
),
(
"2023-03-12 02:00:00",
"America/New_York",
"Exact spring-forward transition moment (gap boundary)",
),
(
"2023-11-05 01:00:00",
"America/New_York",
"Exact fall-back transition moment (overlap boundary)",
),
(
"2024-10-06 02:30:00",
"Australia/Sydney",
"Southern hemisphere spring-forward gap",
),
(
"2023-10-01 12:00:00",
"Pacific/Honolulu",
"Zone with no DST ever (Hawaii)",
),
(
"1800-01-01 12:00:00",
"Europe/London",
"Very old historical (LMT era)",
),
//
(
"2024-06-15 14:30:00",
"Asia/Kathmandu",
"Nepal +5:45 offset (no DST, non-whole-hour)",
),
(
"2024-06-15 14:30:00",
"Australia/Lord_Howe",
"Lord Howe Island +10:30 standard / +11:00 DST (30-minute DST jump)",
),
(
"2024-06-15 14:30:00",
"Australia/Eucla",
"Australian Central Western +8:45 (another 45-minute offset, no DST)",
),
(
"2024-07-15 12:00:00",
"America/Phoenix",
"Arizona fixed UTC-7, never observes DST (contrasts with other US zones)",
),
(
"2024-06-15 14:30:00",
"Pacific/Kiritimati",
"Kiribati +14:00 (most eastern offset on Earth)",
),
(
"2011-12-29 12:00:00",
"Pacific/Apia",
"Samoa BEFORE 2011 dateline jump (UTC-11)",
),
(
"2011-12-31 12:00:00",
"Pacific/Apia",
"Samoa AFTER 2011 dateline jump (UTC+13) — day skipped on 2011-12-30",
),
(
"2024-06-15 14:30:00",
"Europe/Dublin",
"Ireland — uses negative DST modeling in TZDB (can expose subtle bugs)",
),
// North Korea "Pyongyang Time" experiment
(
"2015-08-15 00:00:00",
"Asia/Pyongyang",
"North Korea adopts UTC+8:30 (Pyongyang Time)",
),
(
"2018-05-05 00:00:00",
"Asia/Pyongyang",
"North Korea returns to UTC+9",
),
// US/Canada standard time adoption (LMT → modern zones)
(
"1883-11-17 12:00:00",
"America/New_York",
"Day before US standard time (LMT era)",
),
(
"1883-11-18 12:00:00",
"America/New_York",
"US standard time begins (EST UTC-5 at noon)",
),
("2024-06-15 14:30:00", "US/Eastern", "Zone alias US/Eastern"),
("2024-06-15 14:30:00", "US/Pacific", "Zone alias US/Pacific"),
("2024-06-15 14:30:00", "Etc/UTC", "Etc/UTC alias"),
("2024-06-15 14:30:00", "GMT", "GMT alias"),
(
"2024-06-15 14:30:00",
"Etc/GMT+5",
"Etc/GMT+5 (note: means UTC-5)",
),
("2024-06-15 14:30:00", "Zulu", "Zulu alias (if supported)"),
(
"2024-06-15 14:30:00.123456789",
"America/New_York",
"Full nanosecond precision",
),
(
"2024-06-15 14:30:00.5",
"America/New_York",
"Half-second precision",
),
(
"2024-11-03 01:30:00.999999999",
"America/New_York",
"Subsecond during fall-back overlap",
),
(
"2024-09-29 02:30:00",
"Pacific/Auckland",
"New Zealand spring-forward gap",
),
(
"2024-04-07 02:30:00",
"Pacific/Auckland",
"New Zealand fall-back overlap",
),
(
"2024-10-06 02:00:00",
"America/Santiago",
"Chile spring-forward (recent rule changes)",
),
(
"2024-12-31 23:59:59",
"America/New_York",
"Recent Dec 31 - should be EST",
),
// Far future — safe across almost all zones
("9999-01-01 00:00:00", "UTC", "Year 9999 on UTC (safe)"),
(
"9998-12-31 23:59:59",
"America/New_York",
"Far future year 9998 in EST (still safe)",
),
(
"9999-06-15 12:00:00",
"Pacific/Kiritimati",
"Year 9999 on +14 zone (pushes closest to limit)",
),
// Ancient dates — safe
(
"0002-01-01 00:00:00",
"UTC",
"Year 2 proleptic Gregorian (safe lower bound)",
),
("0001-01-01 00:00:00", "UTC", "Year 1 on UTC only"),
// 1. Fixed-offset zone with NO repeating rules at all (should always return None)
(
"2025-06-15 12:00:00",
"Etc/GMT+12",
"Fixed +12 with no DST ever",
),
(
"2025-06-15 12:00:00",
"Etc/GMT-12",
"Fixed -12 with no DST ever",
),
// 2. A zone that abolished DST relatively recently (tests that we don't wrongly apply old repeating rules)
(
"2025-06-15 12:00:00",
"Asia/Amman",
"Jordan abolished DST in 2022",
),
// 3. Subsecond precision exactly at a transition instant
(
"2023-03-12 02:00:00.000000000",
"America/New_York",
"Exact spring-forward second (nanosecond)",
),
(
"2023-11-05 01:00:00.999999999",
"America/New_York",
"Last nanosecond before fall-back overlap",
),
// 4. Very early date (before most explicit transitions) — should still work via first transition / LMT
("1700-01-01 12:00:00", "Europe/London", "Pre-1800 LMT era"),
// 5. A date far in the future on a zone that has Repeating::None
// (tests that we keep the last known offset forever)
(
"9999-06-15 12:00:00",
"Australia/Eucla",
"Far future on a None zone (+8:45 fixed)",
),
// 6. Overlap/gap with subsecond that lands inside the gap/overlap window
(
"2023-03-12 02:00:00.5",
"America/New_York",
"Half-second inside spring-forward gap",
),
(
"2023-11-05 01:30:00.123456789",
"America/New_York",
"Subsecond deep inside fall-back overlap",
),
// 7. Zone with a very recent rule change that should still get Repeating::None or correct Cycle
(
"2025-03-01 12:00:00",
"Africa/Casablanca",
"Morocco has changed DST rules many times",
),
// 8. A zone whose repeating pattern starts quite late (tests truncation optimization)
(
"2025-06-15 12:00:00",
"America/Argentina/Buenos_Aires",
"Argentina abolished DST in 2009",
),
// 9. Exact transition second in southern hemisphere
(
"2024-10-06 02:00:00.000000000",
"Australia/Sydney",
"Exact spring-forward second (Sydney)",
),
// === More non-existent times (DST spring-forward gaps) ===
(
"2025-03-09 02:30:00",
"America/New_York",
"NY 2025 spring-forward gap (non-existent local time)",
),
(
"2025-03-09 02:00:00",
"America/New_York",
"Exact NY 2025 spring-forward boundary (gap start)",
),
(
"2025-03-09 02:30:00.5",
"America/New_York",
"Half-second inside NY 2025 spring-forward gap",
),
(
"2025-03-30 01:30:00",
"Europe/London",
"London 2025 spring-forward gap (1am→2am BST, non-existent)",
),
(
"2025-03-30 01:00:00",
"Europe/London",
"Exact London 2025 spring-forward boundary",
),
(
"2025-03-30 01:30:00.123456789",
"Europe/London",
"Subsecond deep inside London 2025 spring-forward gap",
),
(
"2025-03-09 02:30:00",
"America/Chicago",
"Chicago 2025 spring-forward gap (different US zone)",
),
(
"2024-10-06 02:30:00.999999999",
"Australia/Sydney",
"Last nanosecond inside Sydney spring-forward gap",
),
(
"2023-10-29 01:30:00",
"Europe/London",
"UK DST fall-back overlap (BST → GMT) - prefers earlier occurrence",
),
// 1. Far future UTC instant → local time (exercises offset_info_at_utc + Cycle)
(
"9999-06-15 12:00:00",
"America/New_York",
"Far future UTC path on repeating zone (NY)",
),
// 2. Another repeating zone far in the future
(
"9998-07-01 00:00:00",
"Europe/London",
"Far future on Europe/London repeating cycle",
),
// 3. A zone that becomes fixed (Repeating::None / Future::Fixed) far in future
(
"9999-01-01 00:00:00",
"Australia/Eucla",
"Far future on a zone that has no repeating rule",
),
// 4. Exact transition moment in far future (tests precision of cycle math)
(
"9999-03-11 07:00:00",
"America/New_York",
"Far future spring-forward transition (UTC path)",
),
// 5. Very far future on a simple repeating zone
(
"3000-12-31 23:59:59",
"America/Chicago",
"Year 3000 on repeating US zone",
),
// ("2006-04-02 02:30-05", "America/Indiana/Vevay", "github"), // errors on jiff temporal
];
for (civil_str, iana_name, description) in cases {
// ─── Jiff ground truth ─────────────────────────────────────────────────────
let civil_dt: DateTime = civil_str
.parse()
.unwrap_or_else(|e| panic!("Jiff civil parse failed for '{}': {}", civil_str, e));
let jiff_zoned: Zoned = civil_dt
.in_tz(iana_name)
.unwrap_or_else(|e| panic!("Jiff in_tz('{}') failed: {}", iana_name, e));
// let jiff_str = jiff_zoned.timestamp().to_string();
let jiff_str = jiff_zoned.to_string();
// ─── deep-time ──────────────────────────────────────────────────────────
let our_input = format!("{} {}", civil_str, iana_name);
let our_dt: Dt = our_input
.parse()
.unwrap_or_else(|e| panic!("deep_time failed on '{}': {}", our_input, e));
let our_str = our_dt.to_str_rfc9557(&format!("{}", iana_name)).unwrap();
// ─── Assert (no more manual prints) ────────────────────────────────────────
assert_eq!(
our_str, jiff_str,
"\n=== IANA Historical Test FAILED: {} ===\n\
Input string : {}\n\
Jiff : {}\n\
deep_time : {}\n",
description, our_input, jiff_str, our_str
);
}
}
#[test]
fn test_offset_handling_with_jiff() {
let cases = vec![
// === Basic whole-hour offsets ===
("2024-06-15 14:30:00", "+00:00", "UTC / +0"),
("2024-06-15 14:30:00", "+05:00", "UTC+5"),
("2024-06-15 14:30:00", "-04:00", "UTC-4 (EDT-style)"),
("2024-06-15 14:30:00", "-05:00", "UTC-5 (EST)"),
("2024-06-15 14:30:00", "+08:00", "UTC+8"),
("2024-06-15 14:30:00", "-12:00", "UTC-12"),
("2024-06-15 14:30:00", "+14:00", "UTC+14 (easternmost)"),
// === Non-whole-hour offsets (the ones that catch bugs) ===
("2024-06-15 14:30:00", "+05:30", "India +5:30"),
("2024-06-15 14:30:00", "+05:45", "Nepal +5:45"),
("2024-06-15 14:30:00", "+08:45", "Australia/Eucla +8:45"),
(
"2024-06-15 14:30:00",
"+10:30",
"Lord Howe +10:30 (standard)",
),
("2024-06-15 14:30:00", "-09:30", "Marquesas Islands -9:30"),
("2024-06-15 14:30:00", "+12:45", "Chatham Islands +12:45"),
// === Subsecond precision ===
(
"2024-06-15 14:30:00.123456789",
"+05:30",
"Full nanosecond precision",
),
("2024-06-15 14:30:00.5", "+08:00", "Half-second precision"),
(
"2024-11-05 01:30:00.999999999",
"-05:00",
"Last nanosecond of a second",
),
// === Historical / far-future / edge cases ===
(
"1800-01-01 12:00:00",
"-00:44",
"Very old fixed offset (LMT era)",
),
(
"1883-11-18 12:00:00",
"-05:00",
"US Standard Time adoption day",
),
("9998-12-31 23:59:59", "+14:00", "Far future +14:00"),
("0001-01-01 00:00:00", "+00:00", "Year 1 with fixed offset"),
// === Z / Zulu alias ===
("2024-06-15 14:30:00", "Z", "Zulu alias (should be +00:00)"),
("2024-06-15 14:30:00", "z", "Lowercase z alias"),
];
for (civil_str, offset_str, description) in cases {
// ─── Jiff ground truth ─────────────────────────────────────────────────────
let civil_with_t = civil_str.replace(' ', "T");
let offset_part = if offset_str.eq_ignore_ascii_case("z") {
"Z"
} else {
offset_str
};
let jiff_input = format!("{}{}", civil_with_t, offset_part);
let jiff_ts: Timestamp = jiff_input.parse().unwrap_or_else(|e| {
panic!(
"Jiff Timestamp::parse failed for '{}': {}\n\
(original civil: {}, offset: {})",
jiff_input, e, civil_str, offset_str
)
});
let jiff_rfc = jiff_ts.to_string();
// ─── deep_time ─────────────────────────────────────────────────────────────
let our_input = format!("{} {}", civil_str, offset_str);
let our_dt: Dt = Dt::from_str_parse(&our_input, &ParseCfg::DEFAULT)
.unwrap_or_else(|e| panic!("deep_time failed on '{}': {}", our_input, e));
let our_rfc = our_dt.to_str_rfc3339();
// ─── Assert ────────────────────────────────────────────────────────────────
assert_eq!(
our_rfc, jiff_rfc,
"\n=== Offset Handling Test FAILED: {} ===\n\
Input string : {}\n\
Jiff input : {}\n\
Jiff : {}\n\
deep_time : {}\n",
description, our_input, jiff_input, jiff_rfc, our_rfc
);
}
}
}