Re-throw all errors from send strategies

src/drivers/send/index.js

@@ -1,7 +1,7 @@
 /* @flow */
 
 import { isWindowClosed, getDomain, type CrossDomainWindowType, type DomainMatcher } from 'cross-domain-utils/src';
-import { uniqueID } from 'belter/src';
+import { uniqueID, stringifyError } from 'belter/src';
 
 import { serializeMessage } from '../../serialize';
 import type { Message } from '../types';
@@ -22,19 +22,18 @@ export function sendMessage(win : CrossDomainWindowType, domain : DomainMatcher,
         }
     }, { on, send });
 
-    let success = false;
-    let error;
+    const strategies = Object.keys(SEND_MESSAGE_STRATEGIES);
+    const errors = [];
 
-    for (const strategyName of Object.keys(SEND_MESSAGE_STRATEGIES)) {
+    for (const strategyName of strategies) {
         try {
             SEND_MESSAGE_STRATEGIES[strategyName](win, serializedMessage, domain);
-            success = true;
         } catch (err) {
-            error = error || err;
+            errors.push(err);
         }
     }
 
-    if (!success) {
-        throw error;
+    if (errors.length === strategies.length) {
+        throw new Error(`All post-robot messaging strategies failed:\n\n${ errors.map(stringifyError).join('\n\n') }`);
     }
 }