internal/fuzz: trim carriage return from version line

On windows hosts, when code is checked out using git with the default
setting of autocrlf=true, carriage returns are appended to source lines
which then prevent the version check from being successful. This removes
carriage returns to allow version matching.

Fixes #52268

Change-Id: I9acc4e907c93a20305f8742cc01687a122a88645
Reviewed-on: https://go-review.googlesource.com/c/go/+/402074
Reviewed-by: Roland Shoemaker <roland@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Dan Kortschak <dan@kortschak.io>
Reviewed-by: Ian Lance Taylor <iant@google.com>

src/internal/fuzz/encoding.go

@@ -12,6 +12,7 @@ import (
 	"go/token"
 	"math"
 	"strconv"
+	"strings"
 	"unicode/utf8"
 )
 
@@ -106,8 +107,9 @@ func unmarshalCorpusFile(b []byte) ([]any, error) {
 	if len(lines) < 2 {
 		return nil, fmt.Errorf("must include version and at least one value")
 	}
-	if string(lines[0]) != encVersion1 {
-		return nil, fmt.Errorf("unknown encoding version: %s", lines[0])
+	version := strings.TrimSuffix(string(lines[0]), "\r")
+	if version != encVersion1 {
+		return nil, fmt.Errorf("unknown encoding version: %s", version)
 	}
 	var vals []any
 	for _, line := range lines[1:] {

src/internal/fuzz/encoding_test.go

@@ -214,6 +214,11 @@ uint(18446744073709551615)`
 				}
 			}(),
 		},
+		{
+			desc: "windows new line",
+			in:   "go test fuzz v1\r\nint(0)\r\n",
+			want: "go test fuzz v1\nint(0)",
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.desc, func(t *testing.T) {