bug: opendal compat doesn't work as expected

[Xuanwo]

Describe the bug

Rust doesn't make sure to generate the same layout for the same struct defination.

Read https://rust-lang.github.io/unsafe-code-guidelines/layout/structs-and-tuples.html for more.

[src/v0_50_to_v0_49.rs:69:9] &new_info = AccessorInfo {
    scheme: Memory,
    root: "/",
    name: "0x7f3a1c00bc60",
    native_capability: { Stat | Read | Write | Delete | List | Blocking },
    full_capability: { Stat | Read | Write | CreateDir | Delete | List | Blocking },
}
[src/v0_50_to_v0_49.rs:71:9] &old_info = AccessorInfo {
    scheme: Memory,
    root: "/",
    name: "0x7f3a1c00bc60",
    native_capability: { Stat | List | Presign },
    full_capability: { Stat | Rename | List | Presign },
}

Steps to Reproduce

use opendal_v0_50 as new_o;

#[tokio::test]
async fn test_read() {
    let new_op = new_o::Operator::from_config(new_o::services::MemoryConfig::default())
        .unwrap()
        .finish();
    let old_op = opendal_compat::v0_50_to_v0_49(new_op);

    old_op.write("test", "hello, world!").await.unwrap();
    let bs = old_op.read("test").await.unwrap();
    assert_eq!(String::from_utf8_lossy(&bs.to_vec()), "hello, world!");
}

This test will failed for:

called `Result::unwrap()` on an `Err` value: Unsupported (permanent) at write => service memory doesn't support operation write

note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace


failures:
    v0_50_to_v0_49::tests::test_read

Expected Behavior

We expect both read and write can work correctly.

Additional Context

No response

Are you willing to submit a PR to fix this bug?

• Yes, I would like to submit a PR.