From b05c9fdf1ba34be6be287d8ae1ddb289db15c824 Mon Sep 17 00:00:00 2001
From: Yash Sharma <yashrsharma44@gmail.com>
Date: Thu, 11 Mar 2021 13:52:27 +0530
Subject: [PATCH] use the main branch's implementation of MultiError

Signed-off-by: Yash Sharma <yashrsharma44@gmail.com>
---
 pkg/errutil/multierror.go |  5 -----
 pkg/route/error.go        |  2 +-
 pkg/route/handler.go      |  2 +-
 pkg/route/handler_test.go | 26 +++++++++++++-------------
 4 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/pkg/errutil/multierror.go b/pkg/errutil/multierror.go
index 23c0cafad7f..aa53706dde6 100644
--- a/pkg/errutil/multierror.go
+++ b/pkg/errutil/multierror.go
@@ -32,11 +32,6 @@ func (es MultiError) Err() error {
 	return NonNilMultiError(es)
 }
 
-// Error implements the error interface.
-func (es MultiError) Error() string {
-	return es.Err().Error()
-}
-
 type NonNilMultiError MultiError
 
 // Returns a concatenated string of the contained errors.
diff --git a/pkg/route/error.go b/pkg/route/error.go
index 3fca4d17c58..a17aacd301f 100644
--- a/pkg/route/error.go
+++ b/pkg/route/error.go
@@ -38,7 +38,7 @@ func determineWriteErrorCause(err error, threshold int) error {
 	}
 
 	unwrappedErr := errors.Cause(err)
-	errs, ok := unwrappedErr.(errutil.MultiError)
+	errs, ok := unwrappedErr.(errutil.NonNilMultiError)
 	if !ok {
 		errs = []error{unwrappedErr}
 	}
diff --git a/pkg/route/handler.go b/pkg/route/handler.go
index 8eda6258540..79e06c548e6 100644
--- a/pkg/route/handler.go
+++ b/pkg/route/handler.go
@@ -486,7 +486,7 @@ func (h *Handler) fanoutForward(pctx context.Context, tenant string, replicas ma
 			return fctx.Err()
 		case err, more := <-ec:
 			if !more {
-				return errs
+				return errs.Err()
 			}
 			if err == nil {
 				success++
diff --git a/pkg/route/handler_test.go b/pkg/route/handler_test.go
index e0220c41cc4..ff73da7261d 100644
--- a/pkg/route/handler_test.go
+++ b/pkg/route/handler_test.go
@@ -49,7 +49,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "nil multierror",
-			err:  errutil.MultiError([]error{}),
+			err:  errutil.NonNilMultiError([]error{}),
 		},
 		{
 			name:      "matching simple",
@@ -59,7 +59,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "non-matching multierror",
-			err: errutil.MultiError([]error{
+			err: errutil.NonNilMultiError([]error{
 				errors.New("foo"),
 				errors.New("bar"),
 			}),
@@ -67,7 +67,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "nested non-matching multierror",
-			err: errors.Wrap(errutil.MultiError([]error{
+			err: errors.Wrap(errutil.NonNilMultiError([]error{
 				errors.New("foo"),
 				errors.New("bar"),
 			}), "baz"),
@@ -76,9 +76,9 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "deep nested non-matching multierror",
-			err: errors.Wrap(errutil.MultiError([]error{
+			err: errors.Wrap(errutil.NonNilMultiError([]error{
 				errors.New("foo"),
-				errutil.MultiError([]error{
+				errutil.NonNilMultiError([]error{
 					errors.New("bar"),
 					errors.New("qux"),
 				}),
@@ -88,7 +88,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "matching multierror",
-			err: errutil.MultiError([]error{
+			err: errutil.NonNilMultiError([]error{
 				storage.ErrOutOfOrderSample,
 				errors.New("foo"),
 				errors.New("bar"),
@@ -98,7 +98,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "matching but below threshold multierror",
-			err: errutil.MultiError([]error{
+			err: errutil.NonNilMultiError([]error{
 				storage.ErrOutOfOrderSample,
 				errors.New("foo"),
 				errors.New("bar"),
@@ -108,7 +108,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "matching multierror many",
-			err: errutil.MultiError([]error{
+			err: errutil.NonNilMultiError([]error{
 				storage.ErrOutOfOrderSample,
 				errConflict,
 				status.Error(codes.AlreadyExists, "conflict"),
@@ -120,7 +120,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "matching multierror many, one above threshold",
-			err: errutil.MultiError([]error{
+			err: errutil.NonNilMultiError([]error{
 				storage.ErrOutOfOrderSample,
 				errConflict,
 				tsdb.ErrNotReady,
@@ -133,7 +133,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "matching multierror many, both above threshold, conflict have precedence",
-			err: errutil.MultiError([]error{
+			err: errutil.NonNilMultiError([]error{
 				storage.ErrOutOfOrderSample,
 				errConflict,
 				tsdb.ErrNotReady,
@@ -147,7 +147,7 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "nested matching multierror",
-			err: errors.Wrap(errors.Wrap(errutil.MultiError([]error{
+			err: errors.Wrap(errors.Wrap(errutil.NonNilMultiError([]error{
 				storage.ErrOutOfOrderSample,
 				errors.New("foo"),
 				errors.New("bar"),
@@ -157,8 +157,8 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 		},
 		{
 			name: "deep nested matching multierror",
-			err: errors.Wrap(errutil.MultiError([]error{
-				errutil.MultiError([]error{
+			err: errors.Wrap(errutil.NonNilMultiError([]error{
+				errutil.NonNilMultiError([]error{
 					errors.New("qux"),
 					status.Error(codes.AlreadyExists, "conflict"),
 					status.Error(codes.AlreadyExists, "conflict"),