0001-test-case-for-lz4.patch

From 38d43e436f9401cc38f2a4d78ca9d17dd521a611 Mon Sep 17 00:00:00 2001
From: Chris Koch <chrisko@google.com>
Date: Sun, 19 Feb 2023 16:38:50 -0800
Subject: [PATCH] Test case for failure to legacy-compress and
 non-legacy-decompress

---
 reader_test.go | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/reader_test.go b/reader_test.go
index 143642c..9b2e008 100644
--- a/reader_test.go
+++ b/reader_test.go
@@ -6,11 +6,13 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"math/rand"
 	"os"
 	"reflect"
 	"runtime"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/pierrec/lz4/v4"
 )
@@ -326,3 +328,44 @@ func TestValidFrameHeader(t *testing.T) {
 		})
 	}
 }
+
+const choices = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+// randomString generates random string of fixed length in a fast and simple way.
+func randomString(l int) string {
+	rand.Seed(time.Now().UnixNano())
+	r := make([]byte, l)
+	for i := 0; i < l; i++ {
+		r[i] = byte(choices[rand.Intn(len(choices))])
+	}
+	return string(r)
+}
+
+func TestLegacyCompressionNonLegacyReader(t *testing.T) {
+	var b bytes.Buffer
+	lz4w := lz4.NewWriter(&b)
+	lz4w.Apply(lz4.LegacyOption(true))
+
+	data := randomString(1024)
+
+	n, err := io.Copy(lz4w, strings.NewReader(data))
+	if err != nil {
+		t.Fatalf("io.Copy = %v", err)
+	}
+	if n != int64(len(data)) {
+		t.Fatalf("Got %d bytes compressed, want %d", n, len(data))
+	}
+	if err := lz4w.Close(); err != nil {
+		t.Fatalf("Failed to close lz4 writer: %v", err)
+	}
+
+	src := lz4.NewReader(bytes.NewReader(b.Bytes()))
+	var buf strings.Builder
+	if _, err := io.Copy(&buf, src); err != nil {
+		t.Errorf("io.Copy = %v", err)
+	}
+	if buf.String() != data {
+		t.Errorf("got %s, want %s", buf.String(), data)
+	}
+
+}
-- 
2.39.2.637.g21b0678d19-goog