1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
use crate::{Dt, DtErr, DtErrKind, Scale, an_err};
use jiff::{SignedDuration, Span, Timestamp};
impl Dt {
/// Converts this `Dt` to a [`jiff::Timestamp`] (always in UTC).
///
/// This is the main/default conversion method for absolute instants.
///
/// - The `Dt` is first converted to TAI internally (respecting all
/// scales, leap seconds, and relativistic models).
/// - The duration since the Unix epoch (1970-01-01 00:00:00 UTC) is then
/// computed.
/// - Sub-nanosecond attoseconds are truncated toward zero.
/// - Saturates at [`Timestamp::MIN`] / [`Timestamp::MAX`] if the instant
/// is outside the range supported by Jiff (roughly years 0000–9999).
/// Never returns an error.
pub fn to_jiff_timestamp(&self) -> Timestamp {
let span_since_epoch = self.to_diff_raw(Dt::UNIX_EPOCH);
let total_nanos = span_since_epoch.to_attos() / 1_000_000_000i128;
match Timestamp::from_nanosecond(total_nanos) {
Ok(ts) => ts,
Err(_) => {
if total_nanos >= 0 {
Timestamp::MAX
} else {
Timestamp::MIN
}
}
}
}
/// Converts this `Dt` to a [`jiff::Span`] (seconds + nanoseconds only).
///
/// This is the **main/default** conversion method.
///
/// - Sub-nanosecond attoseconds are **truncated toward zero**.
/// - The conversion is fully exact up to the nanosecond (using 128-bit integer arithmetic).
/// - **Saturates** at the largest/smallest representable `Span` (roughly ±20,000 years)
/// if the value is out of range.
/// Never returns an error.
pub fn to_jiff_span(&self) -> Span {
let total_nanos = self.to_attos() / 1_000_000_000i128;
let seconds = (total_nanos / 1_000_000_000) as i64;
let nanoseconds = (total_nanos % 1_000_000_000) as i64;
// Fast path when in range
if let Ok(base) = Span::new().try_seconds(seconds) {
if let Ok(span) = base.try_nanoseconds(nanoseconds) {
return span;
}
}
// Saturate to Jiff's Span limits
if total_nanos >= 0 {
Span::new()
.seconds(631_107_417_600i64)
.nanoseconds(999_999_999i64)
} else {
Span::new()
.seconds(-631_107_417_600i64)
.nanoseconds(-999_999_999i64)
}
}
/// Converts this `Span` to a `jiff::SignedDuration` (nanosecond precision).
///
/// - Sub-nanosecond attoseconds are **truncated toward zero**.
/// - Supports the **entire** range of `Span` (never saturates).
#[inline]
pub fn to_jiff_signed_duration(&self) -> SignedDuration {
let total_nanos = self.to_attos() / 1_000_000_000i128;
SignedDuration::from_nanos_i128(total_nanos)
}
/// Creates a `Dt` from a `jiff::Timestamp`.
///
/// This is the exact reverse of [`Dt::to_jiff_timestamp`].
///
/// `jiff::Timestamp` is the primary absolute instant type in the Jiff
/// ecosystem (broadly convertible to `Zoned`, civil datetimes, etc.).
///
/// - The resulting `Dt` is expressed in the TAI scale
/// (the library's canonical internal scale).
/// - Sub-nanosecond attoseconds are set to zero.
#[inline]
pub fn from_jiff_timestamp(ts: Timestamp) -> Self {
Dt::UNIX_EPOCH.add(Dt::from_ns(ts.as_nanosecond(), Scale::TAI))
}
/// Creates a `Dt` from a `jiff::SignedDuration` (nanosecond precision).
///
/// This is the exact reverse of [`Dt::to_jiff_signed_duration`].
#[inline]
pub fn from_jiff_signed_duration(dur: SignedDuration) -> Self {
Self::from_ns(dur.as_nanos(), Scale::TAI)
}
/// Creates a `Dt` from a `jiff::Dt`.
///
/// This is the exact reverse of [`Dt::to_jiff_span`].
///
/// - Works perfectly for pure time-based `Dt`s (seconds + nanoseconds only).
/// - Returns `Err` if the `Dt` contains any calendar units (years, months,
/// weeks, days, etc.) that cannot be converted to a pure elapsed-time
/// duration.
#[inline]
pub fn from_jiff_span(span: Span) -> Result<Self, DtErr> {
let dur = SignedDuration::try_from(span)
.map_err(|e| an_err!(DtErrKind::InvalidInput, "{:?}: {}", span, e))?;
Ok(Self::from_jiff_signed_duration(dur))
}
}