fix(coerce-input-value): input object coercion rejects arrays (#4367)

Author: JoviDeCroock

src/utilities/__tests__/coerceInputValue-test.ts

@@ -122,11 +122,19 @@ describe('coerceInputValue', () => {
   });
 
   describe('for GraphQLInputObject', () => {
+    const DeepObject = new GraphQLInputObjectType({
+      name: 'DeepObject',
+      fields: {
+        foo: { type: new GraphQLNonNull(GraphQLInt) },
+        bar: { type: GraphQLInt },
+      },
+    });
     const TestInputObject = new GraphQLInputObjectType({
       name: 'TestInputObject',
       fields: {
         foo: { type: new GraphQLNonNull(GraphQLInt) },
         bar: { type: GraphQLInt },
+        deepObject: { type: DeepObject },
       },
     });
 
@@ -153,6 +161,14 @@ describe('coerceInputValue', () => {
     it('invalid for an unknown field', () => {
       test({ foo: 123, unknownField: 123 }, TestInputObject, undefined);
     });
+
+    it('invalid for an array type', () => {
+      test([{ foo: 1 }, { bar: 1 }], TestInputObject, undefined);
+    });
+
+    it('invalid for an array type on a nested field', () => {
+      test({ foo: 1, deepObject: [1, 2, 3] }, TestInputObject, undefined);
+    });
   });
 
   describe('for GraphQLInputObject that isOneOf', () => {

src/utilities/coerceInputValue.ts

@@ -64,8 +64,8 @@ export function coerceInputValue(
   }
 
   if (isInputObjectType(type)) {
-    if (!isObjectLike(inputValue)) {
-      return; // Invalid: intentionally return no value.
+    if (!isObjectLike(inputValue) || Array.isArray(inputValue)) {
+      return;
     }
 
     const coercedValue: any = {};