Drop 'Array.from' polyfill (#2912)

src/execution/execute.js

@@ -1,5 +1,3 @@
-import arrayFrom from '../polyfills/arrayFrom';
-
 import type { Path } from '../jsutils/Path';
 import type { ObjMap } from '../jsutils/ObjMap';
 import type { PromiseOrValue } from '../jsutils/PromiseOrValue';
@@ -833,7 +831,7 @@ function completeListValue(
   // where the list contains no Promises by avoiding creating another Promise.
   const itemType = returnType.ofType;
   let containsPromise = false;
-  const completedResults = arrayFrom(result, (item, index) => {
+  const completedResults = Array.from(result, (item, index) => {
     // No need to modify the info object containing the path,
     // since from here on it is not ever accessed by resolver functions.
     const itemPath = addPath(path, index, undefined);

src/jsutils/isCollection.js

@@ -21,7 +21,11 @@ import { SYMBOL_ITERATOR } from '../polyfills/symbols';
  *   An Object value which might implement the Iterable or Array-like protocols.
  * @return {boolean} true if Iterable or Array-like Object.
  */
-export default function isCollection(obj: mixed): boolean {
+declare function isCollection(value: mixed): boolean %checks(value instanceof
+  Iterable);
+
+// eslint-disable-next-line no-redeclare
+export default function isCollection(obj) {
   if (obj == null || typeof obj !== 'object') {
     return false;
   }

src/type/schema.js

@@ -1,4 +1,3 @@
-import arrayFrom from '../polyfills/arrayFrom';
 import objectValues from '../polyfills/objectValues';
 import { SYMBOL_TO_STRING_TAG } from '../polyfills/symbols';
 
@@ -207,7 +206,7 @@ export class GraphQLSchema {
     // Keep track of all implementations by interface name.
     this._implementationsMap = Object.create(null);
 
-    for (const namedType of arrayFrom(allReferencedTypes)) {
+    for (const namedType of Array.from(allReferencedTypes)) {
       if (namedType == null) {
         continue;
       }

src/utilities/astFromValue.js

@@ -1,4 +1,3 @@
-import arrayFrom from '../polyfills/arrayFrom';
 import objectValues from '../polyfills/objectValues';
 
 import inspect from '../jsutils/inspect';
@@ -67,7 +66,7 @@ export function astFromValue(value: mixed, type: GraphQLInputType): ?ValueNode {
       const valuesNodes = [];
       // Since we transpile for-of in loose mode it doesn't support iterators
       // and it's required to first convert iteratable into array
-      for (const item of arrayFrom(value)) {
+      for (const item of Array.from(value)) {
         const itemNode = astFromValue(item, itemType);
         if (itemNode != null) {
           valuesNodes.push(itemNode);

src/utilities/coerceInputValue.js

@@ -1,4 +1,3 @@
-import arrayFrom from '../polyfills/arrayFrom';
 import objectValues from '../polyfills/objectValues';
 
 import type { Path } from '../jsutils/Path';
@@ -79,7 +78,7 @@ function coerceInputValueImpl(
   if (isListType(type)) {
     const itemType = type.ofType;
     if (isCollection(inputValue)) {
-      return arrayFrom(inputValue, (itemValue, index) => {
+      return Array.from(inputValue, (itemValue, index) => {
         const itemPath = addPath(path, index, undefined);
         return coerceInputValueImpl(itemValue, itemType, onError, itemPath);
       });

src/validation/rules/FieldsOnCorrectTypeRule.js

@@ -1,5 +1,3 @@
-import arrayFrom from '../../polyfills/arrayFrom';
-
 import didYouMean from '../../jsutils/didYouMean';
 import suggestionList from '../../jsutils/suggestionList';
 import naturalCompare from '../../jsutils/naturalCompare';
@@ -107,7 +105,7 @@ function getSuggestedTypeNames(
     }
   }
 
-  return arrayFrom(suggestedTypes)
+  return Array.from(suggestedTypes)
     .sort((typeA, typeB) => {
       // Suggest both interface and object types based on how common they are.
       const usageCountDiff = usageCount[typeB.name] - usageCount[typeA.name];