Silver panics on some git repository

Step to reproduce:

cd into problematic git repository (*)
notice silver panics instead of showing prompt

Environment:

FreeBSD 12.1-STABLE amd64
rustc 1.41.1

Backtrace (RUST_BACKTRACE=full) :

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Error { code: -1, klass: 9, message: "object not found - no match for id (e5824806aef1edb462faf1dc540b6538ba3acb0e)" }', src/libcore/result.rs:1188:5
stack backtrace:
   0:          0x170eec7 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h32d82dc921588b09
   1:          0x1728e71 - core::fmt::write::h3db4515aabc4ffad
   2:          0x170ce12 - std::io::Write::write_fmt::h7fd707b71dba37a5
   3:          0x170f8c6 - std::panicking::default_hook::{{closure}}::h611a75bca87583cb
   4:          0x170f561 - std::panicking::default_hook::h73492732b8fc4af1
   5:          0x170ff8f - std::panicking::rust_panic_with_hook::he2e64fc0f6c38bec
   6:          0x170fb53 - rust_begin_unwind
   7:          0x172b3dd - core::panicking::panic_fmt::h50e2d5c221f03579
   8:          0x17286ba - core::result::unwrap_failed::h1e281a90569cce12
   9:          0x12ab841 - core::result::Result<T,E>::unwrap::h302d8abdea227165
                               at /wrkdirs/usr/ports/lang/rust/work/rustc-1.41.1-src/src/libcore/result.rs:956
  10:          0x12a4ee9 - silver::modules::git::segment::ha2446e0eba359d68
                               at src/modules/git.rs:38
  11:          0x12abf69 - silver::modules::handle::ha81b7b61b1d87426
                               at src/modules/mod.rs:19
  12:          0x129ca05 - silver::print::prompt::h3694d5e51ae69af8
                               at src/print.rs:19
  13:          0x129ecff - silver::main::hea77f2ffdf7d4df9
                               at src/main.rs:67
  14:          0x12b6d62 - std::rt::lang_start::{{closure}}::h3272b0ed79d86ac6
                               at /wrkdirs/usr/ports/lang/rust/work/rustc-1.41.1-src/src/libstd/rt.rs:67
  15:          0x170f9d8 - std::panicking::try::do_call::hda18895706f3c060
  16:          0x171087f - __rust_maybe_catch_panic
  17:          0x1706a18 - std::rt::lang_start_internal::hc08c9bcf7cbc0352
  18:          0x12b6d33 - std::rt::lang_start::h240f09e66096250f
                               at /wrkdirs/usr/ports/lang/rust/work/rustc-1.41.1-src/src/libstd/rt.rs:67
  19:          0x129edeb - main
  20:          0x129a10d - _start
                               at /usr/src/lib/csu/amd64/crt1.c:76

reujab / silver

Silver panics on some git repository #28