Retrying without an error code (#82)

src/watch.js

@@ -205,14 +205,24 @@ const DOCUMENT_WATCH_COMPARATOR = (doc1, doc2) => {
 };
 
 /**
- * Determines whether a GRPC Error is considered permanent and should not be
- * retried.
+ * Determines whether an error is considered permanent and should not be
+ * retried. Errors that don't provide a GRPC error code are always considered
+ * transient in this context.
  *
  * @private
- * @param {Error} error A GRPC Error object that exposes an error code.
+ * @param {Error} error An error object.
  * @return {boolean} Whether the error is permanent.
  */
 function isPermanentError(error) {
+  if (error.code === undefined) {
+    Firestore.log(
+      'Watch.onSnapshot',
+      'Unable to determine error code: ',
+      error
+    );
+    return false;
+  }
+
   switch (error.code) {
     case GRPC_STATUS_CODE.CANCELLED:
     case GRPC_STATUS_CODE.UNKNOWN:

test/watch.js

@@ -819,6 +819,18 @@ describe('Query watch', function() {
     return result;
   });
 
+  it('retries with unknown code', function() {
+    return watchHelper.runTest(collQueryJSON(), () => {
+      watchHelper.sendAddTarget();
+      watchHelper.sendCurrent();
+      watchHelper.sendSnapshot(1, [0xabcd]);
+      return watchHelper.await('snapshot').then(() => {
+        streamHelper.destroyStream(new Error('Unknown'));
+        return streamHelper.awaitReopen();
+      });
+    });
+  });
+
   it('handles changing a doc', function() {
     return watchHelper.runTest(collQueryJSON(), () => {
       // Mock the server responding to the query.