Enable Flow on "subscribe-test.js" (#1865)

src/subscription/__tests__/subscribe-test.js

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @noflow
+ * @flow strict
  */
 
 import { expect } from 'chai';
@@ -129,6 +129,7 @@ async function createSubscription(pubsub, schema = emailSchema, ast, vars) {
   // `subscribe` returns Promise<AsyncIterator | ExecutionResult>
   return {
     sendImportantEmail,
+    // $FlowFixMe
     subscription: await subscribe(schema, ast || defaultAST, data, null, vars),
   };
 }
@@ -163,6 +164,7 @@ describe('Subscription Initialization Phase', () => {
       },
     });
 
+    // $FlowFixMe
     ai.return();
   });
 
@@ -224,6 +226,7 @@ describe('Subscription Initialization Phase', () => {
       importantEmail: {},
     });
 
+    // $FlowFixMe
     await subscription.next();
   });
 
@@ -257,6 +260,7 @@ describe('Subscription Initialization Phase', () => {
       importantEmail: {},
     });
 
+    // $FlowFixMe
     await subscription.next();
   });
 
@@ -297,6 +301,7 @@ describe('Subscription Initialization Phase', () => {
     `);
 
     const subscription = await subscribe(testSchema, ast);
+    // $FlowFixMe
     subscription.next(); // Ask for a result, but ignore it.
 
     expect(didResolveImportantEmail).to.equal(true);
@@ -314,23 +319,27 @@ describe('Subscription Initialization Phase', () => {
     `);
 
     await expectPromiseToThrow(
+      // $DisableFlowOnNegativeTest
       () => subscribe(null, document),
       'Expected null to be a GraphQL schema.',
     );
 
     await expectPromiseToThrow(
+      // $DisableFlowOnNegativeTest
       () => subscribe({ document }),
       'Expected undefined to be a GraphQL schema.',
     );
   });
 
   it('throws an error if document is missing', async () => {
     await expectPromiseToThrow(
+      // $DisableFlowOnNegativeTest
       () => subscribe(emailSchema, null),
       'Must provide document',
     );
 
     await expectPromiseToThrow(
+      // $DisableFlowOnNegativeTest
       () => subscribe({ schema: emailSchema }),
       'Must provide document',
     );
@@ -465,6 +474,7 @@ describe('Subscription Initialization Phase', () => {
       },
     };
 
+    // $FlowFixMe
     const result = await subscribe(emailSchema, ast, data, null, {
       priority: 'meow',
     });
@@ -831,6 +841,7 @@ describe('Subscription Publish Phase', () => {
       `),
     );
 
+    // $FlowFixMe
     const payload1 = await subscription.next();
     expect(payload1).to.deep.equal({
       done: false,
@@ -902,6 +913,7 @@ describe('Subscription Publish Phase', () => {
       `),
     );
 
+    // $FlowFixMe
     const payload1 = await subscription.next();
     expect(payload1).to.deep.equal({
       done: false,