zstd feature does not work on wasm

[matthiasbeyer]

Describe the bug

The README says that I can enable the "zstd" feature also for WASM, but that leads to a compile error because the zstd lib cannot be linked.

To Reproduce
Steps to reproduce the behavior:

1. Use this as a dependency with the "zstd" feature
2. Compile for wasm

[Its-Just-Nans]

Hi

Could you give us your Cargo.toml ?
Also the compilation error?

Thanks

cargo new testing
cd testing

cargo add zip --features zstd
cargo build --target wasm32-unknown-unknown

[Its-Just-Nans]

On my side, my personal project https://github.com/Its-Just-Nans/whatisthis is able to compile

(Also it can handle a zstd)

fn main() {
    const IPSUM: &[u8] = b"Lorem ipsum dolor sit amet, consectetur adipiscing elit.";
    use std::io::Write;
    let file = std::fs::File::create("zstd.zip").unwrap();
    let mut zip = zip::ZipWriter::new(file);
    zip.start_file(
        "ipsum.txt",
        zip::write::SimpleFileOptions::default().compression_method(zip::CompressionMethod::Zstd),
    )
    .unwrap();
    zip.write_all(IPSUM).unwrap();

    zip.finish().unwrap();
}