Process futures before using as function arguments

Closes #1538

lib/src/sql/function.rs

@@ -113,6 +113,8 @@ impl Function {
 	) -> Result<Value, Error> {
 		// Prevent long function chains
 		let opt = &opt.dive(1)?;
+		// Ensure futures are run
+		let opt = &opt.futures(true);
 		// Process the function type
 		match self {
 			Self::Cast(s, x) => {

lib/tests/future.rs

@@ -33,3 +33,35 @@ async fn future_function_simple() -> Result<(), Error> {
 	//
 	Ok(())
 }
+
+#[tokio::test]
+async fn future_function_arguments() -> Result<(), Error> {
+	let sql = "
+		UPDATE future:test SET
+			a = 'test@surrealdb.com',
+			b = <future> { 'test@surrealdb.com' },
+			x = 'a-' + parse::email::user(a),
+			y = 'b-' + parse::email::user(b)
+		;
+	";
+	let dbs = Datastore::new("memory").await?;
+	let ses = Session::for_kv().with_ns("test").with_db("test");
+	let res = &mut dbs.execute(&sql, &ses, None, false).await?;
+	assert_eq!(res.len(), 1);
+	//
+	let tmp = res.remove(0).result?;
+	let val = Value::parse(
+		"[
+			{
+				a: 'test@surrealdb.com',
+				b: 'test@surrealdb.com',
+				id: 'future:test',
+				x: 'a-test',
+				y: 'b-test',
+			}
+		]",
+	);
+	assert_eq!(tmp, val);
+	//
+	Ok(())
+}