feat: Waku v2 bridge

Issue #12610

vendor/github.com/anacrolix/missinggo/expvarIndentMap.go

@@ -0,0 +1,35 @@
+package missinggo
+
+import (
+	"bytes"
+	"expvar"
+	"fmt"
+)
+
+type IndentMap struct {
+	expvar.Map
+}
+
+var _ expvar.Var = (*IndentMap)(nil)
+
+func NewExpvarIndentMap(name string) *IndentMap {
+	v := new(IndentMap)
+	v.Init()
+	expvar.Publish(name, v)
+	return v
+}
+
+func (v *IndentMap) String() string {
+	var b bytes.Buffer
+	fmt.Fprintf(&b, "{")
+	first := true
+	v.Do(func(kv expvar.KeyValue) {
+		if !first {
+			fmt.Fprintf(&b, ",")
+		}
+		fmt.Fprintf(&b, "\n\t%q: %v", kv.Key, kv.Value)
+		first = false
+	})
+	fmt.Fprintf(&b, "}")
+	return b.String()
+}