Flow: switched to exact object by default (#3085)

In preparation for TS migration

.eslintrc.yml

@@ -464,7 +464,7 @@ overrides:
       flowtype/no-unused-expressions: off
       flowtype/no-weak-types: [error, { any: false }]
       flowtype/require-compound-type-alias: off
-      flowtype/require-exact-type: off
+      flowtype/require-exact-type: [error, never]
       flowtype/require-indexer-name: error
       flowtype/require-inexact-type: off # checked by Flow
       flowtype/require-parameter-type: off

.flowconfig

@@ -5,10 +5,7 @@
 [include]
 
 [lints]
-sketchy-null-bool=error
-sketchy-null-string=error
-sketchy-null-number=error
-sketchy-null-mixed=error
+sketchy-null=error
 sketchy-number=error
 untyped-type-import=error
 nonstrict-import=off
@@ -20,8 +17,8 @@ unsafe-getters-setters=error
 unnecessary-optional-chain=error
 unnecessary-invariant=error
 signature-verification-failure=error
-implicit-inexact-object=error
-ambiguous-object-type=error
+implicit-inexact-object=off
+ambiguous-object-type=off
 uninitialized-instance-property=error
 default-import-access=error
 invalid-import-star-use=error
@@ -33,6 +30,7 @@ export-renamed-default=error
 [options]
 all=true
 module.use_strict=true
+exact_by_default=true
 experimental.const_params=true
 include_warnings=true
 no_flowlib=true

src/__testUtils__/__tests__/genFuzzStrings-test.js

@@ -3,10 +3,10 @@ import { describe, it } from 'mocha';
 
 import { genFuzzStrings } from '../genFuzzStrings';
 
-function expectFuzzStrings(options: {|
+function expectFuzzStrings(options: {
   allowedChars: Array<string>,
   maxLength: number,
-|}) {
+}) {
   return expect([...genFuzzStrings(options)]);
 }
 

src/__testUtils__/genFuzzStrings.js

@@ -1,10 +1,10 @@
 /**
  * Generator that produces all possible combinations of allowed characters.
  */
-export function* genFuzzStrings(options: {|
+export function* genFuzzStrings(options: {
   allowedChars: Array<string>,
   maxLength: number,
-|}): Generator<string, void, void> {
+}): Generator<string, void, void> {
   const { allowedChars, maxLength } = options;
   const numAllowedChars = allowedChars.length;
 

src/__tests__/starWarsData.js

@@ -10,23 +10,23 @@ export type Character = {
   ...
 };
 
-export type Human = {|
+export type Human = {
   type: 'Human',
   id: string,
   name: string,
   friends: Array<string>,
   appearsIn: Array<number>,
   homePlanet?: string,
-|};
+};
 
-export type Droid = {|
+export type Droid = {
   type: 'Droid',
   id: string,
   name: string,
   friends: Array<string>,
   appearsIn: Array<number>,
   primaryFunction: string,
-|};
+};
 
 /**
  * This defines a basic set of data for our Star Wars Schema.
@@ -79,7 +79,7 @@ const tarkin: Human = {
   appearsIn: [4],
 };
 
-const humanData: {| [id: string]: Human |} = {
+const humanData: { [id: string]: Human } = {
   [luke.id]: luke,
   [vader.id]: vader,
   [han.id]: han,
@@ -105,7 +105,7 @@ const artoo: Droid = {
   primaryFunction: 'Astromech',
 };
 
-const droidData: {| [id: string]: Droid |} = {
+const droidData: { [id: string]: Droid } = {
   [threepio.id]: threepio,
   [artoo.id]: artoo,
 };

src/error/formatError.js

@@ -23,7 +23,7 @@ export function formatError(error: GraphQLError): GraphQLFormattedError {
 /**
  * @see https://github.com/graphql/graphql-spec/blob/master/spec/Section%207%20--%20Response.md#errors
  */
-export type GraphQLFormattedError = {|
+export type GraphQLFormattedError = {
   /**
    * A short, human-readable summary of the problem that **SHOULD NOT** change
    * from occurrence to occurrence of the problem, except for purposes of
@@ -47,4 +47,4 @@ export type GraphQLFormattedError = {|
    * and hence there are no additional restrictions on its contents.
    */
   +extensions?: { [key: string]: mixed, ... },
-|};
+};

src/execution/__tests__/abstract-test.js

@@ -17,11 +17,11 @@ import { buildSchema } from '../../utilities/buildASTSchema';
 
 import { executeSync, execute } from '../execute';
 
-async function executeQuery(args: {|
+async function executeQuery(args: {
   schema: GraphQLSchema,
   query: string,
   rootValue?: mixed,
-|}) {
+}) {
   const { schema, query, rootValue } = args;
   const document = parse(query);
   const result = executeSync({
@@ -534,7 +534,7 @@ describe('Execute: Handles execution of abstract types', () => {
       }
     `);
 
-    function expectError({ forTypeName }: {| forTypeName: mixed |}) {
+    function expectError({ forTypeName }: { forTypeName: mixed }) {
       const rootValue = { pet: { __typename: forTypeName } };
       const result = executeSync({ schema, document, rootValue });
       return {

src/execution/__tests__/lists-test.js

@@ -65,7 +65,7 @@ describe('Execute: Accepts any iterable as list value', () => {
 });
 
 describe('Execute: Handles list nullability', () => {
-  async function complete(args: {| listField: mixed, as: string |}) {
+  async function complete(args: { listField: mixed, as: string }) {
     const { listField, as } = args;
     const schema = buildSchema(`type Query { listField: ${as} }`);
     const document = parse('{ listField }');

src/execution/__tests__/resolve-test.js

@@ -64,7 +64,7 @@ describe('Execute: resolve function', () => {
         this._num = num;
       }
 
-      test(args: {| addend1: number |}, context: {| addend2: number |}) {
+      test(args: { addend1: number }, context: { addend2: number }) {
         return this._num + args.addend1 + context.addend2;
       }
     }

src/execution/execute.js

@@ -92,7 +92,7 @@ import {
  * Namely, schema of the type system that is currently executing,
  * and the fragments defined in the query document
  */
-export type ExecutionContext = {|
+export type ExecutionContext = {
   schema: GraphQLSchema,
   fragments: ObjMap<FragmentDefinitionNode>,
   rootValue: mixed,
@@ -102,7 +102,7 @@ export type ExecutionContext = {|
   fieldResolver: GraphQLFieldResolver<any, any>,
   typeResolver: GraphQLTypeResolver<any, any>,
   errors: Array<GraphQLError>,
-|};
+};
 
 /**
  * The result of GraphQL execution.
@@ -111,19 +111,19 @@ export type ExecutionContext = {|
  *   - `data` is the result of a successful execution of the query.
  *   - `extensions` is reserved for adding non-standard properties.
  */
-export type ExecutionResult = {|
+export type ExecutionResult = {
   errors?: $ReadOnlyArray<GraphQLError>,
   data?: ObjMap<mixed> | null,
   extensions?: ObjMap<mixed>,
-|};
+};
 
-export type FormattedExecutionResult = {|
+export type FormattedExecutionResult = {
   errors?: $ReadOnlyArray<GraphQLFormattedError>,
   data?: ObjMap<mixed> | null,
   extensions?: ObjMap<mixed>,
-|};
+};
 
-export type ExecutionArgs = {|
+export type ExecutionArgs = {
   schema: GraphQLSchema,
   document: DocumentNode,
   rootValue?: mixed,
@@ -132,7 +132,7 @@ export type ExecutionArgs = {|
   operationName?: ?string,
   fieldResolver?: ?GraphQLFieldResolver<any, any>,
   typeResolver?: ?GraphQLTypeResolver<any, any>,
-|};
+};
 
 /**
  * Implements the "Evaluating requests" section of the GraphQL specification.

src/execution/values.js

@@ -23,8 +23,8 @@ import { valueFromAST } from '../utilities/valueFromAST';
 import { coerceInputValue } from '../utilities/coerceInputValue';
 
 type CoercedVariableValues =
-  | {| errors: $ReadOnlyArray<GraphQLError> |}
-  | {| coerced: { [variable: string]: mixed, ... } |};
+  | { errors: $ReadOnlyArray<GraphQLError> }
+  | { coerced: { [variable: string]: mixed, ... } };
 
 /**
  * Prepares an object map of variableValues of the correct type based on the
@@ -41,7 +41,7 @@ export function getVariableValues(
   schema: GraphQLSchema,
   varDefNodes: $ReadOnlyArray<VariableDefinitionNode>,
   inputs: { +[variable: string]: mixed, ... },
-  options?: {| maxErrors?: number |},
+  options?: { maxErrors?: number },
 ): CoercedVariableValues {
   const errors = [];
   const maxErrors = options?.maxErrors;

src/graphql.js

@@ -55,7 +55,7 @@ import { execute } from './execution/execute';
  *    If not provided, the default type resolver is used (which looks for a
  *    `__typename` field or alternatively calls the `isTypeOf` method).
  */
-export type GraphQLArgs = {|
+export type GraphQLArgs = {
   schema: GraphQLSchema,
   source: string | Source,
   rootValue?: mixed,
@@ -64,7 +64,7 @@ export type GraphQLArgs = {|
   operationName?: ?string,
   fieldResolver?: ?GraphQLFieldResolver<any, any>,
   typeResolver?: ?GraphQLTypeResolver<any, any>,
-|};
+};
 
 export function graphql(args: GraphQLArgs): Promise<ExecutionResult> {
   // Always return a Promise for a consistent API.

src/jsutils/Path.js

@@ -1,8 +1,8 @@
-export type Path = {|
+export type Path = {
   +prev: Path | void,
   +key: string | number,
   +typename: string | void,
-|};
+};
 
 /**
  * Given a Path and a key, return a new Path containing the new key.

src/language/__tests__/source-test.js

@@ -25,7 +25,7 @@ describe('Source', () => {
   });
 
   it('rejects invalid locationOffset', () => {
-    function createSource(locationOffset: {| line: number, column: number |}) {
+    function createSource(locationOffset: { line: number, column: number }) {
       return new Source('', '', locationOffset);
     }