Decoding infinity timestamp as chrono::DateTime overflows

[benesch]

Decoding the 'infinity' timestamp explodes because an addition in the decoding overflows. Understood that postgres_types::Timestamp is the way to handle infinity and -infinity, but ideally would get a nice error here rather than an overflow.

use chrono::{DateTime, Utc};

fn main() {
    let mut client = postgres::Client::connect("host=localhost user=benesch", postgres::NoTls).unwrap();
    let x: DateTime<Utc> = client.query_one("SELECT timestamptz 'infinity'", &[]).unwrap().get(0);
    println!("{:?}", x);
}

thread 'main' panicked at '`NaiveDateTime + Duration` overflowed', /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/chrono-0.4.13/src/naive/datetime.rs:1260:9
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/libunwind.rs:86
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:78
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:59
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1069
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1504
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:62
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:49
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:198
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:218
  10: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:511
  11: rust_begin_unwind
             at src/libstd/panicking.rs:419
  12: core::panicking::panic_fmt
             at src/libcore/panicking.rs:111
  13: core::option::expect_failed
             at src/libcore/option.rs:1260
  14: core::option::Option<T>::expect
             at /rustc/c7087fe00d2ba919df1d813c040a5d47e43b0fe7/src/libcore/option.rs:347
  15: <chrono::naive::datetime::NaiveDateTime as core::ops::arith::Add<time::duration::Duration>>::add
             at /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/chrono-0.4.13/src/naive/datetime.rs:1260
  16: postgres_types::chrono_04::<impl postgres_types::FromSql for chrono::naive::datetime::NaiveDateTime>::from_sql
             at /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/postgres-types-0.1.2/src/chrono_04.rs:15
  17: postgres_types::chrono_04::<impl postgres_types::FromSql for chrono::datetime::DateTime<chrono::offset::utc::Utc>>::from_sql
             at /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/postgres-types-0.1.2/src/chrono_04.rs:37
  18: postgres_types::FromSql::from_sql_nullable
             at /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/postgres-types-0.1.2/src/lib.rs:451
  19: tokio_postgres::row::Row::get_inner
             at /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-postgres-0.5.5/src/row.rs:181
  20: tokio_postgres::row::Row::get
             at /home/benesch/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-postgres-0.5.5/src/row.rs:148
  21: rust_postgres_play::main
             at src/main.rs:5
  22: std::rt::lang_start::{{closure}}
             at /rustc/c7087fe00d2ba919df1d813c040a5d47e43b0fe7/src/libstd/rt.rs:67
  23: std::rt::lang_start_internal::{{closure}}
             at src/libstd/rt.rs:52
  24: std::panicking::try::do_call
             at src/libstd/panicking.rs:331
  25: std::panicking::try
             at src/libstd/panicking.rs:274
  26: std::panic::catch_unwind
             at src/libstd/panic.rs:394
  27: std::rt::lang_start_internal
             at src/libstd/rt.rs:51
  28: std::rt::lang_start
             at /rustc/c7087fe00d2ba919df1d813c040a5d47e43b0fe7/src/libstd/rt.rs:67
  29: main
  30: __libc_start_main
  31: _start
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.