You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: vm.rs
    path of file: ./repos/wasmer/lib/api/src/js
    
    the code of the file until where you have to start completion: /// This module is mainly used to create the `VM` types that will hold both
/// the JS values of the `Memory`, `Table`, `Global` and `Function` and also
/// it's types.
/// This module should not be needed any longer (with the exception of the memory)
/// once the type reflection is added to the WebAssembly JS API.
/// https://github.com/WebAssembly/js-types/
use std::{any::Any, fmt};

use js_sys::{
    Function as JsFunction,
    WebAssembly::{self, Memory as JsMemory, Table as JsTable},
};
use serde::{Deserialize, Serialize};
use tracing::trace;
use wasm_bindgen::{JsCast, JsValue};
use wasmer_types::{
    FunctionType, GlobalType, MemoryError, MemoryType, Pages, RawValue, TableType, WASM_PAGE_SIZE,
};

use crate::js::{js_handle::JsHandle, wasm_bindgen_polyfill::Global as JsGlobal};

/// Represents linear memory that is managed by the javascript runtime
#[derive(Clone, Debug, PartialEq)]
pub struct VMMemory {
    pub(crate) memory: JsHandle<JsMemory>,
    pub(crate) ty: MemoryType,
}

unsafe impl Send for VMMemory {}
unsafe impl Sync for VMMemory {}

#[derive(Serialize, Deserialize)]
struct DummyBuffer {
    #[serde(rename = "byteLength")]
    byte_length: u32,
}

impl VMMemory {
    /// Creates a new memory directly from a WebAssemb
    
    pub fn copy(&mut self) -> Result<VMMemory, wasmer_types::MemoryError> {
        let new_memory = crate::js::externals::memory::Memory::js_memory_from_type(&self.ty)?;

        let src = crate::js::externals::memory_view::MemoryView::new_raw(&self.memory);
        let amount = src.data_size() as usize;

        trace!(%amount, "memory copy started");

        let mut dst = crate::js::externals::memory_view::MemoryView::new_raw(&new_memory);
        let dst_size = dst.data_size() as usize;

        if amount > dst_size {
            let delta = amount - dst_size;
            let pages = ((delta - 1) / WASM_PAGE_SIZE) + 1;

            let our_js_memory: &crate::js::externals::memory::JSMemory =
                JsCast::unchecked_from_js_ref(&new_memory);
            our_js_memory.grow(pages as u32).map_err(|err| {
                if err.is_instance_of::<js_sys::RangeError>() {
                    let cur_pages = dst_size;
                    MemoryError::CouldNotGrow {
                        current: Pages(cur_pages as u32),
                        attempted_delta: Pages(pages as u32),
                    }
                } else {
                    MemoryError::Generic(err.as_string().unwrap())
                }
            })?;

            dst = crate::js::externals::memory_view::MemoryView::new_raw(&new_memory);
        }

        src.copy_to_memory(amount as u64, &dst).map_err(|err| {
            wasmer_types::MemoryError::Generic(format!("failed to copy the memory - {}", err))
        })?;

        trace!("memory copy finished (size={})", dst.size().bytes().0);

        Ok(Self {
            memory: JsHandle::new(new_memory),
            ty: self.ty.clone(),
        })
    }