From 1cb11ad8add274cfb727bf41c2933903848d5b9a Mon Sep 17 00:00:00 2001
From: Michael Eischer <michael.eischer@fau.de>
Date: Mon, 1 May 2023 18:03:17 +0200
Subject: [PATCH] mount: enable debug logging for the flaky TestMount test

The test case fails from time to time with an Input/Output error while
trying to access the snapshots directory.
---
 cmd/restic/integration_fuse_test.go |  6 ++++++
 internal/debug/testing.go           | 23 +++++++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 internal/debug/testing.go

diff --git a/cmd/restic/integration_fuse_test.go b/cmd/restic/integration_fuse_test.go
index a99064b8f..b69886024 100644
--- a/cmd/restic/integration_fuse_test.go
+++ b/cmd/restic/integration_fuse_test.go
@@ -12,6 +12,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/restic/restic/internal/debug"
 	"github.com/restic/restic/internal/repository"
 	"github.com/restic/restic/internal/restic"
 	rtest "github.com/restic/restic/internal/test"
@@ -159,6 +160,11 @@ func TestMount(t *testing.T) {
 		t.Skip("Skipping fuse tests")
 	}
 
+	debugEnabled := debug.TestLogToStderr(t)
+	if debugEnabled {
+		defer debug.TestDisableLog(t)
+	}
+
 	env, cleanup := withTestEnvironment(t)
 	// must list snapshots more than once
 	env.gopts.backendTestHook = nil
diff --git a/internal/debug/testing.go b/internal/debug/testing.go
new file mode 100644
index 000000000..c9ceae0ea
--- /dev/null
+++ b/internal/debug/testing.go
@@ -0,0 +1,23 @@
+package debug
+
+import (
+	"log"
+	"os"
+	"testing"
+)
+
+// TestLogToStderr configures debug to log to stderr if not the debug log is
+// not already configured and returns whether logging was enabled.
+func TestLogToStderr(t testing.TB) bool {
+	if opts.isEnabled {
+		return false
+	}
+	opts.logger = log.New(os.Stderr, "", log.LstdFlags)
+	opts.isEnabled = true
+	return true
+}
+
+func TestDisableLog(t testing.TB) {
+	opts.logger = nil
+	opts.isEnabled = false
+}