Migrate from time to jiff library

[Copilot]

Replaces time crate (v0.3) with jiff (v0.2.19) for cleaner time handling APIs and better timezone semantics.

Key API Changes

Types:

• OffsetDateTime → Timestamp (always UTC, no offset confusion)
• UtcOffset → TimeZone

Methods:

• .unix_timestamp() → .as_second()
• .nanosecond() → .subsec_nanosecond()
• OffsetDateTime::now_utc() → Timestamp::now()

Benefits

• Explicit UTC semantics (Timestamp is always UTC)
• Built-in serde support without feature flags
• Handles pre-epoch times correctly
• Cleaner timezone API: TimeZone::system() vs UtcOffset::current_local_offset()

Files Modified

• Core: src/unix_time.rs (simplified from 79 to 11 lines)
• Time handling: src/{band,entry,change}.rs, src/index/entry.rs, src/source/entry.rs
• Transport: src/transport/{local,sftp,s3}.rs
• Display: src/{show,bin/conserve,restore}.rs
• Tests: tests/{old_archives,s3_integration}.rs

All modified files formatted with cargo fmt (import ordering, line breaks).

Original prompt

Could you draft a PR that converts from using the time library to using the newer jiff, and assess if that's cleaner or simpler?

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[sourcefrog]

@copilot maybe just delete this now, unless it's actually used?

[sourcefrog]

@copilot actually please see if more of this file can be reduced or deleted?

[Copilot]

Simplified in commit 26345ae. Removed all three traits (ToTimestamp, ToFileTime, FromUnixAndNanos) and replaced with:

• Simple helper functions for the two needed conversions
• jiff's built-in Timestamp::try_from(SystemTime) for SystemTime conversions

The file went from 79 lines to 18 lines.

[sourcefrog]

@copilot resolve the merge conflicts in this pull request

[Copilot]

@copilot resolve the merge conflicts in this pull request

Resolved in commit aa7bbf7. Merged with main branch and fixed conflicts by using the ToFileTime trait approach and updating method calls in restore.rs. All 144 library tests pass.

[Copilot]

Pull request overview

This PR migrates the codebase’s time handling from the time crate to jiff, updating timestamp/duration operations and adjusting dependencies to align with the new time API.

Changes:

• Update backup duration calculations to use jiff::Timestamp/jiff::Span instead of subtraction on time types.
• Adjust tests to use jiff span calculations for elapsed time assertions.
• Remove the time feature flag from tracing-subscriber configuration in Cargo.toml.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/show.rs	Switches displayed backup-duration computation to jiff spans and converts to std::time::Duration for formatting.
src/band.rs	Updates a timing-related test to compute elapsed time via jiff::Timestamp::since.
Cargo.toml	Removes tracing-subscriber’s explicit time feature from the feature list.

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[Copilot]

end_time.since(info.start_time).unwrap() can panic if the span computation fails (e.g., corrupted metadata, out-of-range timestamps, or any error case since reports). Since this is user-facing output, handle the Err case and fall back to something like "unknown"/"negative" instead of panicking.

Suggested change

	let span = end_time.since(info.start_time).unwrap();
	// Convert jiff::Span to std::time::Duration
	match span.total(jiff::Unit::Nanosecond) {
	Ok(total_nanos) if total_nanos >= 0.0 => {
	let duration = std::time::Duration::from_nanos(total_nanos as u64);
	duration_to_hms(duration).into()
	}
	_ => Cow::Borrowed("negative"),
	match end_time.since(info.start_time) {
	Ok(span) => {
	// Convert jiff::Span to std::time::Duration
	match span.total(jiff::Unit::Nanosecond) {
	Ok(total_nanos) if total_nanos >= 0.0 => {
	let duration =
	std::time::Duration::from_nanos(total_nanos as u64);
	duration_to_hms(duration).into()
	}
	_ => Cow::Borrowed("negative"),
	}
	}
	Err(_) => Cow::Borrowed("unknown"),

[Copilot]

Converting Span to Duration via span.total(Unit::Nanosecond) (a float) and as u64 is lossy (truncation) and can silently saturate on out-of-range values. Prefer an integer-based conversion (or a TryFrom/helper provided by jiff for converting to std::time::Duration) and explicitly handle negative/out-of-range spans instead of relying on float casts.

Suggested change

	// Convert jiff::Span to std::time::Duration
	match span.total(jiff::Unit::Nanosecond) {
	Ok(total_nanos) if total_nanos >= 0.0 => {
	let duration = std::time::Duration::from_nanos(total_nanos as u64);
	duration_to_hms(duration).into()
	}
	_ => Cow::Borrowed("negative"),
	match std::time::Duration::try_from(span) {
	Ok(duration) => duration_to_hms(duration).into(),
	Err(_) => Cow::Borrowed("negative"),

[sourcefrog]

Done elsewhere