add Fuzz testing for ParseTraceHeader

xray/fuzz_test.go

@@ -4,6 +4,7 @@
 package xray
 
 import (
+	"reflect"
 	"regexp"
 	"strings"
 	"testing"
@@ -23,3 +24,25 @@ func FuzzSanitizeSegmentName(f *testing.F) {
 		}
 	})
 }
+
+func FuzzParseTraceHeader(f *testing.F) {
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5")
+	f.Add("ROOT=1-5E645F3E-1DFAD076A177C5CCC5DE12F5")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;Parent=03babb4ba280be51")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;Sampled=1")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;Sampled=0")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;Sampled=?")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;foo=bar;hoge=fuga")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;foo")
+	f.Add("Root=1-5e645f3e-1dfad076a177c5ccc5de12f5;Sampled=invalid")
+	f.Add("foo=bar;hoge=fuga;Sampled=1;Parent=03babb4ba280be51;Root=1-5e645f3e-1dfad076a177c5ccc5de12f5")
+
+	f.Fuzz(func(t *testing.T, s string) {
+		h0 := ParseTraceHeader(s)
+		h1 := ParseTraceHeader(h0.String())
+		if !reflect.DeepEqual(h0, h1) {
+			t.Errorf("parsing result not match: %q and %q: input %q", h0, h1, s)
+		}
+	})
+}

xray/testdata/fuzz/FuzzParseTraceHeader/6365bf7e9c6aed1b5da879a515c5306c3a101d1ccd9fe5f337dd55b8d7b5e9f3

@@ -0,0 +1,2 @@
+go test fuzz v1
+string("0; =")

xray/trace_header.go

@@ -43,6 +43,7 @@ func ParseTraceHeader(s string) TraceHeader {
 	var header TraceHeader
 	s = strings.TrimSpace(s)
 	for _, kv := range strings.Split(s, ";") {
+		kv := strings.TrimSpace(kv)
 		idx := strings.IndexByte(kv, '=')
 		if idx < 0 {
 			// ignore invalid parameter