The pdu_len(&self) function returns an error len issue

[ThinkCodeStudio]

Sorry, English is not my main language. The following content will be translated and modified by AI

Excuse me, is this issue a feature or a bug:

I passed in a 200-byte buff, but the function returned the len of the buff

let mut ret = Vec::new();
            let (event, pack) = self.extract_pack();
+            let mut wirte_buff: [u8; 200] = [0; 200];
            let handler_ret = match event {
                CmdTableWidgetEvent::Read => self.modbus_encoder(
                    modbus_client,
                    modbus_addr,
                    RequestPdu(modbus_core::Request::ReadHoldingRegisters(
                        pack[0].addr,
                        pack.len() as u16,
                    )),
                ),
                CmdTableWidgetEvent::Write => self.modbus_encoder(
                    modbus_client,
                    modbus_addr,
                    RequestPdu(if pack.len() > 1 {
                        let addr = pack[0].addr;
                        let words: Vec<u16> = pack.into_iter().map(|it| it.value).collect();
                        // TODO: unwrap() Risk
                        modbus_core::Request::WriteMultipleRegisters(
                            addr,
+                            Data::from_words(words.as_slice(), &mut wirte_buff).unwrap(),
                        )
                    } else {
                        modbus_core::Request::WriteSingleRegister(pack[0].addr, pack[0].value)
                    }),
                ),
            };

The problem lies here

# src/frame/mod.rs : 378
impl Request<'_> {
    /// Number of bytes required for a serialized PDU frame.
    #[must_use]
    pub const fn pdu_len(&self) -> usize {
        match *self {
            Self::ReadCoils(_, _)
            | Self::ReadDiscreteInputs(_, _)
            | Self::ReadInputRegisters(_, _)
            | Self::ReadHoldingRegisters(_, _)
            | Self::WriteSingleRegister(_, _)
            | Self::WriteSingleCoil(_, _) => 5,
            Self::WriteMultipleCoils(_, coils) => 6 + coils.packed_len(),
-           Self::WriteMultipleRegisters(_, words) => 6 + words.data.len(),
+          Self::WriteMultipleRegisters(_, words) => 6 + words.len(),
-           Self::ReadWriteMultipleRegisters(_, _, _, words) => 10 + words.data.len(),
+           Self::ReadWriteMultipleRegisters(_, _, _, words) => 10 + words.len(),
            Self::Custom(_, data) => 1 + data.len(),
            #[cfg(feature = "rtu")]
            _ => todo!(), // TODO
        }
    }
}

[flosse]

Excuse me, is this issue a feature or a bug:

It looks like it is a bug 🫢

[flosse]

@ThinkCodeStudio would you mind to test #34?

[ThinkCodeStudio]

OK! It's working properly in my APP.