Make flow check async

Libraries/JavaScriptAppEngine/Initialization/InitializeJavaScriptAppEngine.js

@@ -59,6 +59,13 @@ function setUpRedBoxConsoleErrorHandler() {
   }
 }
 
+function setupFlowChecker() {
+  if (__DEV__) {
+    var checkFlowAtRuntime = require('checkFlowAtRuntime');
+    checkFlowAtRuntime();
+  }
+}
+
 /**
  * Sets up a set of window environment wrappers that ensure that the
  * BatchedBridge is flushed after each tick. In both the case of the
@@ -143,3 +150,4 @@ setUpGeolocation();
 setUpWebSockets();
 setupProfile();
 setUpProcessEnv();
+setupFlowChecker();

Libraries/JavaScriptAppEngine/Initialization/checkFlowAtRuntime.js

@@ -0,0 +1,59 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @providesModule checkFlowAtRuntime
+ *
+ */
+'use strict';
+
+function checkFlowAtRuntime() {
+  var url = getPackagerURL();
+  if (!url) {
+    return;
+  }
+  fetch(url + 'flow/')
+    .then(response => response.json())
+    .then(response => {
+      if (response.silentError) {
+        return;
+      }
+      throw {
+        message: response.message,
+        stack: response.errors.map(err => {
+          return {
+            ...err,
+            methodName: err.description,
+            file: err.filename,
+          };
+        }),
+      };
+    },
+    () => {
+    //if fetch fails, silently give up
+    })
+    .done();
+}
+
+function getPackagerURL() {
+  var NativeModules = require('NativeModules');
+  var scriptURL = (NativeModules
+    && NativeModules.SourceCode
+    && NativeModules.SourceCode.scriptURL)
+    || '';
+
+  // extract the url of the packager from the whole scriptURL
+  // we match until the first / after http(s)://
+  // i.e. http://www.mypackger.com/debug/my/bundle -> http://www.mypackger.com/
+  return getFirstOrNull(scriptURL.match(/^https?:\/\/[^/]+\//));
+}
+
+function getFirstOrNull(ar) {
+  return ar ? ar[0] : null;
+}
+
+module.exports = checkFlowAtRuntime;

Libraries/JavaScriptAppEngine/Initialization/parseErrorStack.js

@@ -32,7 +32,7 @@ function parseErrorStack(e, sourceMapInstance) {
     return [];
   }
 
-  var stack = stacktraceParser.parse(e.stack);
+  var stack = Array.isArray(e.stack) ? e.stack : stacktraceParser.parse(e.stack);
 
   var framesToPop = e.framesToPop || 0;
   while (framesToPop--) {