From 252ba39c27c8fe3e88488391b7c8189f53e4cc0f Mon Sep 17 00:00:00 2001
From: Pat Hickey <phickey@fastly.com>
Date: Thu, 21 Oct 2021 14:15:53 -0700
Subject: [PATCH] implement table _async methods, test passes now

---
 crates/wasmtime/src/externals.rs | 50 ++++++++++++++++++++++++++++++++
 tests/all/limits.rs              | 14 +++++----
 2 files changed, 58 insertions(+), 6 deletions(-)

diff --git a/crates/wasmtime/src/externals.rs b/crates/wasmtime/src/externals.rs
index d267bf14a7..686b154472 100644
--- a/crates/wasmtime/src/externals.rs
+++ b/crates/wasmtime/src/externals.rs
@@ -436,6 +436,31 @@ impl Table {
         Table::_new(store.as_context_mut().0, ty, init)
     }
 
+    /// Async variant of [`Table::new`]. You must use this variant with [`Store`]s which have a
+    /// [`ResourceLimiterAsync`].
+    ///
+    /// # Panics
+    ///
+    /// This function will panic when used with a non-async [`Store`].
+    #[cfg(feature = "async")]
+    pub async fn new_async<T>(
+        mut store: impl AsContextMut<Data = T>,
+        ty: TableType,
+        init: Val,
+    ) -> Result<Table>
+    where
+        T: Send,
+    {
+        let mut store = store.as_context_mut();
+        assert!(
+            store.0.async_support(),
+            "cannot use `new_async` without enabling async support on the config"
+        );
+        store
+            .on_fiber(|store| Table::_new(store.0, ty, init))
+            .await?
+    }
+
     fn _new(store: &mut StoreOpaque, ty: TableType, init: Val) -> Result<Table> {
         let wasmtime_export = generate_table_export(store, &ty)?;
         let init = init.into_table_element(store, ty.element())?;
@@ -562,6 +587,31 @@ impl Table {
         }
     }
 
+    /// Async variant of [`Table::grow`]. Required when using a [`ResourceLimiterAsync`].
+    ///
+    /// # Panics
+    ///
+    /// This function will panic when used with a non-async [`Store`].
+    #[cfg(feature = "async")]
+    pub async fn grow_async<T>(
+        &self,
+        mut store: impl AsContextMut<Data = T>,
+        delta: u32,
+        init: Val,
+    ) -> Result<u32>
+    where
+        T: Send,
+    {
+        let mut store = store.as_context_mut();
+        assert!(
+            store.0.async_support(),
+            "cannot use `grow_async` without enabling async support on the config"
+        );
+        store
+            .on_fiber(|store| self.grow(store, delta, init))
+            .await?
+    }
+
     /// Copy `len` elements from `src_table[src_index..]` into
     /// `dst_table[dst_index..]`.
     ///
diff --git a/tests/all/limits.rs b/tests/all/limits.rs
index 3a5388cf20..c19ab4b047 100644
--- a/tests/all/limits.rs
+++ b/tests/all/limits.rs
@@ -134,19 +134,21 @@ async fn test_limits_async() -> Result<()> {
     // Test instance exports and host objects hitting the limit
     for table in std::array::IntoIter::new([
         instance.get_table(&mut store, "t").unwrap(),
-        Table::new(
+        Table::new_async(
             &mut store,
             TableType::new(ValType::FuncRef, 0, None),
             Val::FuncRef(None),
-        )?,
+        )
+        .await?,
     ]) {
-        table.grow(&mut store, 2, Val::FuncRef(None))?;
-        table.grow(&mut store, 1, Val::FuncRef(None))?;
-        table.grow(&mut store, 2, Val::FuncRef(None))?;
+        table.grow_async(&mut store, 2, Val::FuncRef(None)).await?;
+        table.grow_async(&mut store, 1, Val::FuncRef(None)).await?;
+        table.grow_async(&mut store, 2, Val::FuncRef(None)).await?;
 
         assert_eq!(
             table
-                .grow(&mut store, 1, Val::FuncRef(None))
+                .grow_async(&mut store, 1, Val::FuncRef(None))
+                .await
                 .map_err(|e| e.to_string())
                 .unwrap_err(),
             "failed to grow table by `1`"