BzEncoder::new with Compression::none fails with -2

[igankevich]

While I was fuzzying my project I noticed that BzEncoder does not accept Compression::none(), although the documentation mentions 0 as a valid value.

Here is the code to reproduce the error.

use bzip2::write::BzEncoder;
use bzip2::Compression;

fn main() {
    let mut _encoder = BzEncoder::new(Vec::new(), Compression::none());
}

And here is the output.

thread 'main' panicked at /src/index.crates.io-6f17d22bba15001f/bzip2-0.4.4/src/mem.rs:123:13:
assertion `left == right` failed
  left: -2
 right: 0
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::assert_failed_inner
   3: core::panicking::assert_failed
             at /tmp/guix-build-rust-1.80.0.drv-0/rustc-1.80.0-src/library/core/src/panicking.rs:363:5
   4: bzip2::mem::Compress::new
             at /src/index.crates.io-6f17d22bba15001f/bzip2-0.4.4/src/mem.rs:123:13
   5: bzip2::write::BzEncoder<W>::new
             at /src/index.crates.io-6f17d22bba15001f/bzip2-0.4.4/src/write.rs:36:19
   6: bzip_test::main
             at ./src/main.rs:5:24
   7: core::ops::function::FnOnce::call_once
             at /tmp/guix-build-rust-1.80.0.drv-0/rustc-1.80.0-src/library/core/src/ops/function.rs:250:5

So, either the documentation or the code is wrong 😃