From 3affc2e066de0253810b8ca2d3c1af827817e8d2 Mon Sep 17 00:00:00 2001
From: Nick Craig-Wood <nick@craig-wood.com>
Date: Tue, 1 Sep 2020 17:55:06 +0100
Subject: [PATCH] fspath: make JoinRootPath convert backslashes to slashes on
 Windows

The function is used for contructing remotes which may have
backslashes in on Windows.
---
 fs/fspath/path.go      | 13 ++++++++++---
 fs/fspath/path_test.go |  2 ++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/fs/fspath/path.go b/fs/fspath/path.go
index d16c29310..a07b7ceea 100644
--- a/fs/fspath/path.go
+++ b/fs/fspath/path.go
@@ -105,14 +105,21 @@ func Split(remote string) (parent string, leaf string, err error) {
 // JoinRootPath joins any number of path elements into a single path, adding a
 // separating slash if necessary. The result is Cleaned; in particular,
 // all empty strings are ignored.
+//
 // If the first non empty element has a leading "//" this is preserved.
+//
+// If the path contains \ these will be converted to / on Windows.
 func JoinRootPath(elem ...string) string {
-	for i, e := range elem {
+	es := make([]string, len(elem))
+	for i := range es {
+		es[i] = filepath.ToSlash(elem[i])
+	}
+	for i, e := range es {
 		if e != "" {
 			if strings.HasPrefix(e, "//") {
-				return "/" + path.Clean(strings.Join(elem[i:], "/"))
+				return "/" + path.Clean(strings.Join(es[i:], "/"))
 			}
-			return path.Clean(strings.Join(elem[i:], "/"))
+			return path.Clean(strings.Join(es[i:], "/"))
 		}
 	}
 	return ""
diff --git a/fs/fspath/path_test.go b/fs/fspath/path_test.go
index 135708ec8..c07379030 100644
--- a/fs/fspath/path_test.go
+++ b/fs/fspath/path_test.go
@@ -2,6 +2,7 @@ package fspath
 
 import (
 	"fmt"
+	"path/filepath"
 	"runtime"
 	"strings"
 	"testing"
@@ -153,6 +154,7 @@ func TestJoinRootPath(t *testing.T) {
 		{[]string{"", "//server/sub", "path"}, "//server/sub/path"},
 		{[]string{"", "//server", "//path"}, "//server/path"},
 		{[]string{"", "//server/sub", "//path"}, "//server/sub/path"},
+		{[]string{"", filepath.FromSlash("//server/sub"), filepath.FromSlash("//path")}, "//server/sub/path"},
 	} {
 		got := JoinRootPath(test.elements...)
 		assert.Equal(t, test.want, got)