From 7167d4e4c76333e1a2d7cd420ea18104ade7bbc6 Mon Sep 17 00:00:00 2001
From: Emmanuel Odeke <emm.odeke@gmail.com>
Date: Tue, 12 Dec 2017 01:15:36 -0700
Subject: [PATCH] types: compile type assertions to avoid sneaky runtime
 surprises

Ensure that the types in result.go implement both
json.Marshaler and json.Unmarshaler
and thus avoid any accidental deletions of their respective
methods which would then cause surprises at runtime.
---
 types/result.go | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/types/result.go b/types/result.go
index 782dbac6a..34df4a046 100644
--- a/types/result.go
+++ b/types/result.go
@@ -2,6 +2,7 @@ package types
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 
 	"github.com/gogo/protobuf/jsonpb"
@@ -137,3 +138,18 @@ func (r *ResponseCommit) UnmarshalJSON(b []byte) error {
 	reader := bytes.NewBuffer(b)
 	return jsonpbUnmarshaller.Unmarshal(reader, r)
 }
+
+// Some compile time assertions to ensure we don't
+// have accidental runtime surprises later on.
+
+// jsonEncodingRoundTripper ensures that asserted
+// interfaces implement both MarshalJSON and UnmarshalJSON
+type jsonRoundTripper interface {
+	json.Marshaler
+	json.Unmarshaler
+}
+
+var _ jsonRoundTripper = (*ResponseCommit)(nil)
+var _ jsonRoundTripper = (*ResponseQuery)(nil)
+var _ jsonRoundTripper = (*ResponseDeliverTx)(nil)
+var _ jsonRoundTripper = (*ResponseSetOption)(nil)