From ce81cc0802e3968bafcfb765d8c7aa023ac8996d Mon Sep 17 00:00:00 2001
From: Phil Pluckthun <phil@kitten.sh>
Date: Tue, 21 Jul 2020 20:34:25 +0100
Subject: [PATCH] (graphcache) - Mute warnings when using built-in fields

See: https://spectrum.chat/urql/help/is-there-a-way-to-access-cache-directly~40669292-345e-4c02-b5ca-64c95f776762?m=MTU5NTIzMDA5MDQ0Ng==
---
 .changeset/chatty-poems-rescue.md                | 5 +++++
 exchanges/graphcache/src/ast/schemaPredicates.ts | 6 ++++--
 2 files changed, 9 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/chatty-poems-rescue.md

diff --git a/.changeset/chatty-poems-rescue.md b/.changeset/chatty-poems-rescue.md
new file mode 100644
index 0000000000..bb4113b61a
--- /dev/null
+++ b/.changeset/chatty-poems-rescue.md
@@ -0,0 +1,5 @@
+---
+'@urql/exchange-graphcache': patch
+---
+
+Mute warning when using built-in GraphQL fields, like `__type`
diff --git a/exchanges/graphcache/src/ast/schemaPredicates.ts b/exchanges/graphcache/src/ast/schemaPredicates.ts
index f936711d5d..906e650904 100644
--- a/exchanges/graphcache/src/ast/schemaPredicates.ts
+++ b/exchanges/graphcache/src/ast/schemaPredicates.ts
@@ -17,12 +17,14 @@ import {
   OptimisticMutationConfig,
 } from '../types';
 
+const BUILTIN_FIELD_RE = /^__/;
+
 export const isFieldNullable = (
   schema: GraphQLSchema,
   typename: string,
   fieldName: string
 ): boolean => {
-  if (fieldName === '__schema') return true;
+  if (BUILTIN_FIELD_RE.test(fieldName)) return true;
   const field = getField(schema, typename, fieldName);
   return !!field && isNullableType(field.type);
 };
@@ -43,7 +45,7 @@ export const isFieldAvailableOnType = (
   typename: string,
   fieldName: string
 ): boolean => {
-  if (fieldName === '__schema') return true;
+  if (BUILTIN_FIELD_RE.test(fieldName)) return true;
   return !!getField(schema, typename, fieldName);
 };