Function trapping

tests/all/call_hook.rs:415–545

()

#[test]
fn trapping() -> Result<(), Error> {
    const TRAP_IN_F: i32 = 0;
    const TRAP_NEXT_CALL_HOST: i32 = 1;
    const TRAP_NEXT_RETURN_HOST: i32 = 2;
    const TRAP_NEXT_CALL_WASM: i32 = 3;
    const TRAP_NEXT_RETURN_WASM: i32 = 4;

    let engine = Engine::default();

    let mut linker = Linker::new(&engine);

    linker.func_wrap(
        "host",
        "f",
        |mut caller: Caller<State>, action: i32, recur: i32| -> Result<()> {
            assert_eq!(caller.data().context.last(), Some(&Context::Host));
            assert_eq!(caller.data().calls_into_host, caller.data().calls_into_wasm);

            match action {
                TRAP_IN_F => bail!("trapping in f"),
                TRAP_NEXT_CALL_HOST => caller.data_mut().trap_next_call_host = true,
                TRAP_NEXT_RETURN_HOST => caller.data_mut().trap_next_return_host = true,
                TRAP_NEXT_CALL_WASM => caller.data_mut().trap_next_call_wasm = true,
                TRAP_NEXT_RETURN_WASM => caller.data_mut().trap_next_return_wasm = true,
                _ => {} // Do nothing
            }

            // recur so that we can trigger a next call.
            // propagate its trap, if it traps!
            if recur > 0 {
                let _ = caller
                    .get_export("export")
                    .expect("caller exports \"export\"")
                    .into_func()
                    .expect("export is a func")
                    .typed::<(i32, i32), ()>(&caller)
                    .expect("export typing")
                    .call(&mut caller, (action, 0))?;
            }

            Ok(())
        },
    )?;

    let wat = r#"
        (module
            (import "host" "f"
                (func $f (param i32) (param i32)))
            (func (export "export") (param i32) (param i32)
                (call $f (local.get 0) (local.get 1)))
        )
    "#;
    let module = Module::new(&engine, wat)?;

    let run = |action: i32, recur: bool| -> (State, Option<Error>) {
        let mut store = Store::new(&engine, State::default());
        store.call_hook(sync_call_hook);
        let inst = linker