Handle errors despite timeouts (#71)

* Ensures that timeouts don't prevent errors from getting into the _errors array.

* Replaces a test that used internal knowledge with a test targeted towards actual use cases.

Co-authored-by: Danny Rivers <drivers@roirevolution.com>

lib/retry_operation.js

@@ -50,6 +50,7 @@ RetryOperation.prototype.retry = function(err) {
   }
   var currentTime = new Date().getTime();
   if (err && currentTime - this._operationStart >= this._maxRetryTime) {
+    this._errors.push(err);
     this._errors.unshift(new Error('RetryOperation timeout occurred'));
     return false;
   }

test/integration/test-retry-operation.js

@@ -256,3 +256,38 @@ var retry = require(common.dir.lib + '/retry');
 
   fn();
 })();
+
+(function testErrorsPreservedWhenMaxRetryTimeExceeded() {
+  var error = new Error('some error');
+  var maxRetryTime = 30;
+  var operation = retry.operation({
+      minTimeout: 1,
+      maxRetryTime: maxRetryTime
+  });
+
+  var finalCallback = fake.callback('finalCallback');
+  fake.expectAnytime(finalCallback);
+
+  var longAsyncFunction = function (wait, callback){
+    setTimeout(callback, wait);
+  };
+
+  var fn = function() {
+    var startTime = new Date().getTime();
+    operation.attempt(function() {
+
+      var curTime = new Date().getTime();
+      longAsyncFunction(maxRetryTime - (curTime - startTime - 1), function(){
+        if (operation.retry(error)) {
+          assert.fail('timeout should be occurred');
+          return;
+        }
+
+        assert.strictEqual(operation.mainError(), error);
+        finalCallback();
+      });
+    });
+  };
+
+  fn();
+})();