Panic on non-UTF-8 tags in music file

[linkmauve]

I have a music file I can’t modify, which contains SHIFT_JIS-encoded tags (it’s a Wave file containing INAM=東方紅魔郷).

What would be your preferred way to handle this issue? Asking the user to provide the encoding, guessing it, or even to ignore any non-UTF-8 tag and act as if it wasn’t present?

I personally don’t need the tags, but other users might.

Here is the full traceback:

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Utf8Error { valid_up_to: 0, error_len: Some(1) }', /home/linkmauve/.cargo/registry/src/github.com-1ecc6299db9ec823/ears-0.7.0/src/sndfile.rs:383:17
stack backtrace:
r   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/libunwind.rs:88
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:77
   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:1052
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1426
   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:204
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:224
  10: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:472
  11: rust_begin_unwind
             at src/libstd/panicking.rs:380
  12: core::panicking::panic_fmt
             at src/libcore/panicking.rs:85
  13: core::option::expect_none_failed
             at src/libcore/option.rs:1199
  14: core::result::Result<T,E>::unwrap
             at /rustc/c2d141df59703393c0c683abc259f9a8c3be041a/src/libcore/result.rs:963
  15: ears::sndfile::SndFile::get_string
             at /home/linkmauve/.cargo/registry/src/github.com-1ecc6299db9ec823/ears-0.7.0/src/sndfile.rs:383
  16: ears::audio_tags::get_sound_tags
             at /home/linkmauve/.cargo/registry/src/github.com-1ecc6299db9ec823/ears-0.7.0/src/audio_tags.rs:84
  17: ears::music::Music::new
             at /home/linkmauve/.cargo/registry/src/github.com-1ecc6299db9ec823/ears-0.7.0/src/music.rs:132
  18: menu::main
             at examples/menu.rs:119
  19: std::rt::lang_start::{{closure}}
             at /rustc/c2d141df59703393c0c683abc259f9a8c3be041a/src/libstd/rt.rs:67
  20: std::rt::lang_start_internal::{{closure}}
             at src/libstd/rt.rs:52
  21: std::panicking::try::do_call
             at src/libstd/panicking.rs:305
  22: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:86
  23: std::panicking::try
             at src/libstd/panicking.rs:281
  24: std::panic::catch_unwind
             at src/libstd/panic.rs:394
  25: std::rt::lang_start_internal
             at src/libstd/rt.rs:51
  26: std::rt::lang_start
             at /rustc/c2d141df59703393c0c683abc259f9a8c3be041a/src/libstd/rt.rs:67
  27: main
  28: __libc_start_main
  29: _start
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

[nickbrowne]

Ah that's definitely not ideal...

I think for now treating non-UTF-8 tags as empty is fine, and a lot better than a panic. If someone really needs to read non-UTF-8 tags then we can possibly add something more elaborate in the future.