Support yield in do expression (#10101)

Co-authored-by: Huáng Jùnliàng <jlhwung@gmail.com>

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/await-yield/exec.js

@@ -0,0 +1,15 @@
+async function* asyncGenerator(x) {
+  const y = do {
+    let z;
+    yield 3;
+    yield await x;
+  };
+
+  return y;
+}
+
+const promise = Promise.resolve(5);
+const gen = asyncGenerator(promise);
+expect(gen.next()).resolves.toMatchObject({ value: 3, done: false });
+expect(gen.next()).resolves.toMatchObject({ value: 5, done: false });
+expect(gen.next(10)).resolves.toMatchObject({ value: 10, done: true });

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/await-yield/input.js

@@ -0,0 +1,8 @@
+async function* asyncGenerator(x) {
+  const y = do {
+    let z;
+    yield await x;
+  };
+
+  return y;
+}

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/await-yield/options.json

@@ -0,0 +1,3 @@
+{
+  "minNodeVersion": "10.0.0"
+}

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/await-yield/output.js

@@ -0,0 +1,7 @@
+async function* asyncGenerator(x) {
+  const y = yield* async function* () {
+    let z;
+    return yield await x;
+  }();
+  return y;
+}

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/yield/exec.js

@@ -0,0 +1,14 @@
+function * generator() {
+  yield 1;
+  const y = do {
+    let z;
+    yield 2;
+  };
+
+  return y;
+}
+
+const gen = generator();
+expect(gen.next().value).toBe(1);
+expect(gen.next().value).toBe(2);
+expect(gen.next(3).value).toBe(3);

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/yield/input.js

@@ -0,0 +1,8 @@
+function * g() {
+  const y = do {
+    let z;
+    yield 1;
+  };
+
+  return y;
+}

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/yield/options.json

@@ -0,0 +1,3 @@
+{
+  "minNodeVersion": "8.0.0"
+}

packages/babel-plugin-proposal-do-expressions/test/fixtures/do-expressions/yield/output.js

@@ -0,0 +1,7 @@
+function* g() {
+  const y = yield* function* () {
+    let z;
+    return yield 1;
+  }();
+  return y;
+}