From 85f9bd1abf9ec4ec2a187294de01bbd759183746 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Wed, 19 Aug 2020 18:04:16 +0100
Subject: [PATCH] union: fix tests by looking for fs.ErrorDirNotFound found in
 Purge and About

Before this change we errored out if one upstream errored in Purge or
About.

This change checks for fs.ErrorDirNotFound and skips that backend in
this case.
---
 backend/union/union.go             | 6 ++++++
 backend/union/upstream/upstream.go | 3 +++
 2 files changed, 9 insertions(+)

diff --git a/backend/union/union.go b/backend/union/union.go
index a803a7e51..1c178d9ab 100644
--- a/backend/union/union.go
+++ b/backend/union/union.go
@@ -181,6 +181,9 @@ func (f *Fs) Purge(ctx context.Context, dir string) error {
 	errs := Errors(make([]error, len(upstreams)))
 	multithread(len(upstreams), func(i int) {
 		err := upstreams[i].Features().Purge(ctx, dir)
+		if errors.Cause(err) == fs.ErrorDirNotFound {
+			err = nil
+		}
 		errs[i] = errors.Wrap(err, upstreams[i].Name())
 	})
 	return errs.Err()
@@ -504,6 +507,9 @@ func (f *Fs) About(ctx context.Context) (*fs.Usage, error) {
 	}
 	for _, u := range f.upstreams {
 		usg, err := u.About(ctx)
+		if errors.Cause(err) == fs.ErrorDirNotFound {
+			continue
+		}
 		if err != nil {
 			return nil, err
 		}
diff --git a/backend/union/upstream/upstream.go b/backend/union/upstream/upstream.go
index 2a58048e8..d8679a091 100644
--- a/backend/union/upstream/upstream.go
+++ b/backend/union/upstream/upstream.go
@@ -335,6 +335,9 @@ func (f *Fs) updateUsageCore(lock bool) error {
 	usage, err := f.RootFs.Features().About(ctx)
 	if err != nil {
 		f.cacheUpdate = false
+		if errors.Cause(err) == fs.ErrorDirNotFound {
+			err = nil
+		}
 		return err
 	}
 	if lock {