This patch fixes the case where a negative millisecond offset is passed
to Timezone::timestamp_millis and timestamp_millis_opt and adds a test
case for it. Without this patch, calling timestamp_offset with a
negative value will panic with an overflow like this:
```
---- tests::test_parse_samples stdout ----
thread 'tests::test_parse_samples' panicked at 'attempt to multiply with
overflow',
/home/c/.cargo/registry/src/github.com-1ecc6299db9ec823/chrono-0.4.6/src/offset/mod.rs:349:34
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a
verbose backtrace.
stack backtrace:
0: std::sys::unix::backtrace::tracing:👿:unwind_backtrace
at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
1: std::sys_common::backtrace::print
at libstd/sys_common/backtrace.rs:71
at libstd/sys_common/backtrace.rs:59
2: std::panicking::default_hook::{{closure}}
at libstd/panicking.rs:211
3: std::panicking::default_hook
at libstd/panicking.rs:221
4: std::panicking::rust_panic_with_hook
at libstd/panicking.rs:477
5: std::panicking::continue_panic_fmt
at libstd/panicking.rs:391
6: rust_begin_unwind
at libstd/panicking.rs:326
7: core::panicking::panic_fmt
at libcore/panicking.rs:77
8: core::panicking::panic
at libcore/panicking.rs:52
9: chrono::offset::TimeZone::timestamp_millis_opt
at
/home/c/.cargo/registry/src/github.com-1ecc6299db9ec823/chrono-0.4.6/src/offset/mod.rs:349
10: chrono::offset::TimeZone::timestamp_millis
at
/home/c/.cargo/registry/src/github.com-1ecc6299db9ec823/chrono-0.4.6/src/offset/mod.rs:327
```
Documentation added to both `impl`s and functions so that they are
visible to both users perusing the online documentation and in
autocomplete/intellisense engines.
And fail CI in the future if `make readme` isn't run when it is needed.
CC conversation in #185, where the README didn't get updated for a year after
lib.rs was improved.
It is the backcompat scheme that we have. In the 5.x timeline we will add the
more-standard and significantly-more-pleasant-to-expand `#[doc(hidden)]
__DoNotMatchAgainstMe` trick.
Casey Marshall
Brandon W Maister
Igor Gnatenko
Vasili Revelas
Pascal Bach
Mahmoud Al-Qudsi
Finkelman
Eh2406
Alejandro Fernández
David Wood
storyfeet
novacrazy
寧靜
Evan Schwartz