From 15f3b35f4bd3609fcfbe4ed862eea748e340bf62 Mon Sep 17 00:00:00 2001
From: Luna Ruan <luna@fb.com>
Date: Wed, 16 Dec 2020 11:53:51 -0800
Subject: [PATCH] clone json obj in react native flight client host config
 parser (#20474)

As per Seb's comment in #20465, we need to do the same thing in React Native as we do in Relay.

When `parseModel` suspends because of missing dependencies, it will exit and retry to parse later. However, in the relay implementation, the model is an object that we modify in place when we parse it, so when we we retry, part of the model might be parsed already into React elements, which will error because the parsing code expect a Flight model. This diff clones instead of mutating the original model, which fixes this error.
---
 .../src/ReactFlightNativeRelayClientHostConfig.js   | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/packages/react-server-native-relay/src/ReactFlightNativeRelayClientHostConfig.js b/packages/react-server-native-relay/src/ReactFlightNativeRelayClientHostConfig.js
index b13d18b3c4098..7ff02159bb7ef 100644
--- a/packages/react-server-native-relay/src/ReactFlightNativeRelayClientHostConfig.js
+++ b/packages/react-server-native-relay/src/ReactFlightNativeRelayClientHostConfig.js
@@ -36,18 +36,25 @@ function parseModelRecursively(response: Response, parentObj, value) {
   }
   if (typeof value === 'object' && value !== null) {
     if (Array.isArray(value)) {
+      const parsedValue = [];
       for (let i = 0; i < value.length; i++) {
-        (value: any)[i] = parseModelRecursively(response, value, value[i]);
+        (parsedValue: any)[i] = parseModelRecursively(
+          response,
+          value,
+          value[i],
+        );
       }
-      return parseModelTuple(response, value);
+      return parseModelTuple(response, parsedValue);
     } else {
+      const parsedValue = {};
       for (const innerKey in value) {
-        (value: any)[innerKey] = parseModelRecursively(
+        (parsedValue: any)[innerKey] = parseModelRecursively(
           response,
           value,
           value[innerKey],
         );
       }
+      return parsedValue;
     }
   }
   return value;