1 files changed, 51 insertions, 0 deletions
diff --git a/internal/config/fuzz_test.go b/internal/config/fuzz_test.go
new file mode 100644
index 0000000..32926d6
--- /dev/null
+++ b/internal/config/fuzz_test.go
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package config
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+	"time"
+)
+
+// FuzzParseSize: a size either fails to parse or is a non-negative number
+// of bytes that reads back the same written as plain digits - no overflow
+// ever wraps a huge size negative.
+func FuzzParseSize(f *testing.F) {
+	for _, s := range []string{"50M", "0", "1T", "9223372036854775807", "8388608T", "8388607T", "-1", "1.5G", "", "G", "007K"} {
+		f.Add(s)
+	}
+	f.Fuzz(func(t *testing.T, s string) {
+		v, err := ParseSize(s)
+		if err != nil {
+			return
+		}
+		if v < 0 {
+			t.Fatalf("ParseSize(%q) = %d, negative", s, v)
+		}
+		if back, err := ParseSize(strconv.FormatInt(v, 10)); err != nil || back != v {
+			t.Fatalf("ParseSize(%q) = %d, which reads back as %d, %v", s, v, back, err)
+		}
+	})
+}
+
+// FuzzParseDuration: a duration either fails to parse or is a non-negative
+// whole number of seconds that reads back the same written in seconds.
+func FuzzParseDuration(f *testing.F) {
+	for _, s := range []string{"30d", "0s", "2m", "1w", "15250284452w", "9223372036s", "d", "", "-1d", "1.5h"} {
+		f.Add(s)
+	}
+	f.Fuzz(func(t *testing.T, s string) {
+		d, err := ParseDuration(s)
+		if err != nil {
+			return
+		}
+		if d < 0 || d%time.Second != 0 {
+			t.Fatalf("ParseDuration(%q) = %v", s, d)
+		}
+		if back, err := ParseDuration(fmt.Sprintf("%ds", d/time.Second)); err != nil || back != d {
+			t.Fatalf("ParseDuration(%q) = %v, which reads back as %v, %v", s, d, back, err)
+		}
+	})
+}