perf: Improve jsonpath speed (#348)

jsonpath/jsonpath_bench_test.go

@@ -0,0 +1,11 @@
+package jsonpath
+
+import "testing"
+
+func BenchmarkEval(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Eval("ids[0]", []byte(`{"ids": [1, 2]}`))
+		Eval("long.simple.walk", []byte(`{"long": {"simple": {"walk": "value"}}}`))
+		Eval("data[0].apps[1].name", []byte(`{"data": [{"apps": [{"name":"app1"}, {"name":"app2"}, {"name":"app3"}]}]}`))
+	}
+}