1 files changed, 29 insertions, 0 deletions
diff --git a/_content/doc/tutorial/fuzz/reverse_test.go b/_content/doc/tutorial/fuzz/reverse_test.go
new file mode 100644
index 0000000..929e340
--- /dev/null
+++ b/_content/doc/tutorial/fuzz/reverse_test.go
@@ -0,0 +1,29 @@
+package main
+
+import (
+	"testing"
+	"unicode/utf8"
+)
+
+func FuzzReverse(f *testing.F) {
+	testcases := []string{"Hello, world", " ", "!12345"}
+	for _, tc := range testcases {
+		f.Add(tc) // Use f.Add to provide a seed corpus
+	}
+	f.Fuzz(func(t *testing.T, orig string) {
+		rev, err1 := Reverse(orig)
+		if err1 != nil {
+			return
+		}
+		doubleRev, err2 := Reverse(rev)
+		if err2 != nil {
+			return
+		}
+		if orig != doubleRev {
+			t.Errorf("Before: %q, after: %q", orig, doubleRev)
+		}
+		if utf8.ValidString(orig) && !utf8.ValidString(rev) {
+			t.Errorf("Reverse produced invalid UTF-8 string %q", rev)
+		}
+	})
+}