From 1ed7c52b29e15057f31d8146c0ec9fd8b5d26308 Mon Sep 17 00:00:00 2001
From: Daniel Olano <daniel@olanod.com>
Date: Mon, 4 Jan 2021 18:34:49 +0100
Subject: [PATCH] Add stream feature to futures crate

---
 crates/futures/Cargo.toml     | 5 ++++-
 crates/futures/README.md      | 3 +++
 crates/futures/src/lib.rs     | 1 +
 crates/futures/tests/tests.rs | 8 ++++++--
 4 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/crates/futures/Cargo.toml b/crates/futures/Cargo.toml
index 28b1cd1d253d..641a96c6800a 100644
--- a/crates/futures/Cargo.toml
+++ b/crates/futures/Cargo.toml
@@ -14,7 +14,10 @@ edition = "2018"
 cfg-if = "1.0.0"
 js-sys = { path = "../js-sys", version = '0.3.46' }
 wasm-bindgen = { path = "../..", version = '0.2.69' }
-futures-core =  { version = '0.3.8', default-features = false }
+futures-core =  { version = '0.3.8', default-features = false, optional = true }
+
+[features]
+stream = ['futures-core']
 
 [target.'cfg(target_feature = "atomics")'.dependencies.web-sys]
 path = "../web-sys"
diff --git a/crates/futures/README.md b/crates/futures/README.md
index 9f6518fef81d..0c0bffe7a213 100644
--- a/crates/futures/README.md
+++ b/crates/futures/README.md
@@ -8,6 +8,9 @@ This crate bridges the gap between a Rust `Future` and a JavaScript
 1. From a JavaScript `Promise` into a Rust `Future`.
 2. From a Rust `Future` into a JavaScript `Promise`.
 
+Additionally under the feature flag `stream` there is experimental 
+support for `AsyncIterator` to `Stream` conversion.
+
 See the [API documentation][docs] for more info.
 
 [docs]: https://rustwasm.github.io/wasm-bindgen/api/wasm_bindgen_futures/
diff --git a/crates/futures/src/lib.rs b/crates/futures/src/lib.rs
index 26ee20dc9c24..03eb0f2682f1 100644
--- a/crates/futures/src/lib.rs
+++ b/crates/futures/src/lib.rs
@@ -43,6 +43,7 @@ use std::task::{Context, Poll, Waker};
 use wasm_bindgen::prelude::*;
 
 mod queue;
+#[cfg(feature = "stream")]
 pub mod stream;
 
 mod task {
diff --git a/crates/futures/tests/tests.rs b/crates/futures/tests/tests.rs
index ad95736722fe..a400e003412e 100644
--- a/crates/futures/tests/tests.rs
+++ b/crates/futures/tests/tests.rs
@@ -3,8 +3,8 @@
 wasm_bindgen_test::wasm_bindgen_test_configure!(run_in_browser);
 
 use futures_channel::oneshot;
-use wasm_bindgen::{prelude::*, JsCast};
-use wasm_bindgen_futures::{future_to_promise, spawn_local, stream::JsStream, JsFuture};
+use wasm_bindgen::prelude::*;
+use wasm_bindgen_futures::{future_to_promise, spawn_local, JsFuture};
 use wasm_bindgen_test::*;
 
 #[wasm_bindgen_test]
@@ -89,9 +89,13 @@ async fn can_create_multiple_futures_from_same_promise() {
     b.await.unwrap();
 }
 
+#[cfg(feature = "stream")]
 #[wasm_bindgen_test]
 async fn can_use_an_async_iterable_as_stream() {
     use futures_lite::stream::StreamExt;
+    use wasm_bindgen::JsCast;
+    use wasm_bindgen_futures::stream::JsStream;
+
     let async_iter = js_sys::Function::new_no_args(
         "return async function*() { 
             yield 42;