Implicit instantiation codemod

Summary:
This diff adds explicit type arguments to polymorphic function calls that do not constrain their types. This codemod will reduce the error burden that will come in a future version of flow.

This specific diff was generated by running:
```
flow codemod annotate-implicit-instantiations --write .
flow --json --pretty | jq '.errors | .[] | .message | .[] | .loc |.source' | sort | uniq | sed -e 's/"//g' | xargs hg revert
hg st -n | xargs grep "generated" | sed -e 's/:.*//g' | xargs hg revert
arc f
```

So these are the codemod results that introduced no new errors and no generated files.

Changelog: [Internal]

drop-conflicts

Reviewed By: SamChou19815

Differential Revision: D40413074

fbshipit-source-id: 42b52719978f1098169662b503dbcfd8cefdad53

packages/metro-file-map/src/ModuleMap.js

@@ -23,7 +23,7 @@ import H from './constants';
 import * as fastPath from './lib/fast_path';
 
 const EMPTY_OBJ: {[string]: ModuleMetaData} = {};
-const EMPTY_MAP = new Map();
+const EMPTY_MAP = new Map<'g' | 'native' | string, ?DuplicatesSet>();
 
 export default class ModuleMap implements IModuleMap<SerializableModuleMap> {
   static DuplicateHasteCandidatesError: Class<DuplicateHasteCandidatesError>;
@@ -191,7 +191,7 @@ export default class ModuleMap implements IModuleMap<SerializableModuleMap> {
     }
     // Force flow refinement
     const previousSet = relativePathSet;
-    const duplicates = new Map();
+    const duplicates = new Map<string, number>();
 
     for (const [relativePath, type] of previousSet) {
       const duplicatePath = fastPath.resolve(this._raw.rootDir, relativePath);

packages/metro-file-map/src/crawlers/node.js

@@ -9,6 +9,7 @@
  * @oncall react_native
  */
 
+import type {Path, FileMetaData} from '../flow-types';
 import type {
   CrawlerOptions,
   FileData,
@@ -224,7 +225,7 @@ module.exports = async function nodeCrawl(options: CrawlerOptions): Promise<{
 
   return new Promise(resolve => {
     const callback = (list: Result) => {
-      const files = new Map();
+      const files = new Map<Path, FileMetaData>();
       const removedFiles = new Map(data.files);
       list.forEach(fileData => {
         const [filePath, mtime, size] = fileData;

packages/metro-react-native-interop-tools/src/type-comparison.js

@@ -171,8 +171,8 @@ function compareObjectType(
   right: ObjectTypeAnnotation,
   isInFunctionReturn: boolean,
 ): Array<ComparisonResult> {
-  const leftProps = new Map();
-  const rightProps = new Map();
+  const leftProps = new Map<string, ObjectTypeProperty>();
+  const rightProps = new Map<string, ObjectTypeProperty>();
   const finalResult = [];
   left.properties.forEach(prop => {
     leftProps.set(prop.name, prop);

packages/metro-resolver/src/__tests__/index-test.js

@@ -22,7 +22,7 @@ type FileTreeNode = $ReadOnly<{
 }>;
 
 const CONTEXT: ResolutionContext = (() => {
-  const fileSet = new Set();
+  const fileSet = new Set<string>();
   (function fillFileSet(fileTree: FileTreeNode, prefix: string) {
     for (const entName in fileTree) {
       const entPath = path.join(prefix, entName);

packages/metro-runtime/src/modules/HMRClient.js

@@ -147,9 +147,9 @@ class HMRClient extends EventEmitter {
 }
 
 function mergeUpdates(base: HmrUpdate, next: HmrUpdate): HmrUpdate {
-  const addedIDs = new Set();
-  const deletedIDs = new Set();
-  const moduleMap = new Map();
+  const addedIDs = new Set<number>();
+  const deletedIDs = new Set<number>();
+  const moduleMap = new Map<number, HmrModule>();
 
   // Fill in the temporary maps and sets from both updates in their order.
   applyUpdateLocally(base);

packages/metro-runtime/src/polyfills/require.js

@@ -558,7 +558,7 @@ if (__DEV__) {
     }
 
     const Refresh = requireRefresh();
-    const refreshBoundaryIDs = new Set();
+    const refreshBoundaryIDs = new Set<ModuleID>();
 
     // In this loop, we will traverse the dependency tree upwards from the
     // changed module. Updates "bubble" up to the closest accepted parent.
@@ -646,7 +646,7 @@ if (__DEV__) {
 
     // If we reached here, it is likely that hot reload will be successful.
     // Run the actual factories.
-    const seenModuleIDs = new Set();
+    const seenModuleIDs = new Set<ModuleID>();
     for (let i = 0; i < updatedModuleIDs.length; i++) {
       const updatedID = updatedModuleIDs[i];
       if (seenModuleIDs.has(updatedID)) {
@@ -754,8 +754,8 @@ if (__DEV__) {
     earlyStop: T => boolean,
   ): Array<T> {
     const result = [];
-    const visited = new Set();
-    const stack = new Set();
+    const visited = new Set<mixed>();
+    const stack = new Set<mixed>();
     function traverseDependentNodes(node: T) {
       if (stack.has(node)) {
         throw CYCLE_DETECTED;
@@ -902,7 +902,7 @@ if (__DEV__) {
       if (key === '__esModule') {
         continue;
       }
-      const desc = Object.getOwnPropertyDescriptor(moduleExports, key);
+      const desc = Object.getOwnPropertyDescriptor<any>(moduleExports, key);
       if (desc && desc.get) {
         // Don't invoke getters as they may have side effects.
         return false;
@@ -949,7 +949,7 @@ if (__DEV__) {
       if (key === '__esModule') {
         continue;
       }
-      const desc = Object.getOwnPropertyDescriptor(moduleExports, key);
+      const desc = Object.getOwnPropertyDescriptor<any>(moduleExports, key);
       if (desc && desc.get) {
         continue;
       }
@@ -972,7 +972,7 @@ if (__DEV__) {
       return;
     }
     for (const key in moduleExports) {
-      const desc = Object.getOwnPropertyDescriptor(moduleExports, key);
+      const desc = Object.getOwnPropertyDescriptor<any>(moduleExports, key);
       if (desc && desc.get) {
         // Don't invoke getters as they may have side effects.
         continue;

packages/metro-source-map/src/Consumer/MappingsConsumer.js

@@ -104,7 +104,7 @@ class MappingsConsumer extends AbstractConsumer implements IConsumer {
 
     const {mappings: mappingsRaw, names} = this._sourceMap;
     let next;
-    const vlqCache = new Map();
+    const vlqCache = new Map<string, any>();
     for (let i = 0; i < mappingsRaw.length; i = next) {
       switch (mappingsRaw[i]) {
         case ';':

packages/metro-transform-plugins/src/import-export-plugin.js

@@ -267,7 +267,7 @@ function importExportPlugin({types: t}: {types: Types, ...}): PluginObj<State> {
 
             if (remote.type === 'StringLiteral') {
               // https://babeljs.io/docs/en/babel-plugin-syntax-module-string-names
-              throw path.buildCodeFrameError(
+              throw path.buildCodeFrameError<$FlowFixMeEmpty>(
                 'Module string names are not supported',
               );
             }

packages/metro/src/Assets.js

@@ -90,7 +90,7 @@ function buildAssetMap(
   const assets = files.map((file: string) =>
     AssetPaths.tryParse(file, platforms),
   );
-  const map = new Map();
+  const map = new Map<string, {files: Array<string>, scales: Array<number>}>();
   assets.forEach(function (asset: ?AssetPath, i: number) {
     if (asset == null) {
       return;

packages/metro/src/Bundler/util.js

@@ -194,7 +194,7 @@ function createRamBundleGroups<T: ModuleTransportLike>(
 
   if (ramGroups.length > 1) {
     // build a map of all grouped module IDs to an array of group root IDs
-    const all = new ArrayMap();
+    const all = new ArrayMap<number, number>();
     for (const [parent, children] of result) {
       for (const module of children) {
         all.get(module).push(parent);

packages/metro/src/DeltaBundler/Serializers/getRamBundleInfo.js

@@ -110,7 +110,7 @@ async function getRamBundleInfo(
       dependenciesByPath: Map<string, ModuleTransportLike>,
     ): Set<number> => {
       const deps = getTransitiveDependencies(module.sourcePath, graph);
-      const output = new Set();
+      const output = new Set<number>();
 
       for (const dependency of deps) {
         const module = dependenciesByPath.get(dependency);

packages/metro/src/DeltaBundler/__tests__/DeltaCalculator-test.js

@@ -9,7 +9,7 @@
  * @oncall react_native
  */
 
-import type {Module, Options} from '../types.flow';
+import type {Module, Options, Dependency} from '../types.flow';
 import type {Result} from '../Graph';
 import CountingSet from '../../lib/CountingSet';
 import {Graph} from '../Graph';
@@ -124,21 +124,21 @@ describe('DeltaCalculator', () => {
         getSource: () => Buffer.of(),
       };
       barModule = {
-        dependencies: new Map(),
+        dependencies: new Map<string, Dependency>(),
         inverseDependencies: new CountingSet(['/bundle']),
         output: [],
         path: '/bar',
         getSource: () => Buffer.of(),
       };
       bazModule = {
-        dependencies: new Map(),
+        dependencies: new Map<string, Dependency>(),
         inverseDependencies: new CountingSet(['/bundle']),
         output: [],
         path: '/baz',
         getSource: () => Buffer.of(),
       };
       quxModule = {
-        dependencies: new Map(),
+        dependencies: new Map<string, Dependency>(),
         inverseDependencies: new CountingSet(['/foo']),
         output: [],
         path: '/qux',
@@ -346,7 +346,7 @@ describe('DeltaCalculator', () => {
     });
 
     const quxModule: Module<$FlowFixMe> = {
-      dependencies: new Map(),
+      dependencies: new Map<string, Dependency>(),
       inverseDependencies: new CountingSet(),
       output: [],
       path: '/qux',

packages/metro/src/DeltaBundler/__tests__/Graph-test.js

@@ -43,7 +43,7 @@ let mockedDependencyTree: Map<
     }>,
   >,
 > = new Map();
-const files = new Set();
+const files = new Set<string>();
 let graph: TestGraph;
 let options;
 
@@ -190,9 +190,9 @@ function computeDelta(
   modules2: ReadOnlyDependencies<>,
   modifiedPaths: Set<string>,
 ) {
-  const added = new Set();
-  const modified = new Set();
-  const deleted = new Set();
+  const added = new Set<string>();
+  const modified = new Set<string>();
+  const deleted = new Set<string>();
 
   for (const id of modules1.keys()) {
     if (!modules2.has(id)) {
@@ -219,7 +219,7 @@ function computeInverseDependencies(
   graph: ReadOnlyGraph<>,
   options: Options<>,
 ) {
-  const allInverseDependencies = new Map();
+  const allInverseDependencies = new Map<string, Set<string>>();
   for (const path of graph.dependencies.keys()) {
     allInverseDependencies.set(path, new Set());
   }
@@ -267,7 +267,7 @@ class TestGraph extends Graph<> {
       this,
       options,
     );
-    const actualInverseDependencies = new Map();
+    const actualInverseDependencies = new Map<string, Set<string>>();
     for (const [path, module] of graph.dependencies) {
       actualInverseDependencies.set(path, new Set(module.inverseDependencies));
     }
@@ -278,7 +278,7 @@ class TestGraph extends Graph<> {
 }
 
 function getMatchingContextModules<T>(graph: Graph<T>, filePath: string) {
-  const contextPaths = new Set();
+  const contextPaths = new Set<string>();
   graph.markModifiedContextModules(filePath, contextPaths);
   return contextPaths;
 }
@@ -2816,7 +2816,7 @@ describe('optional dependencies', () => {
   let localGraph;
   let localOptions;
   const getAllDependencies = () => {
-    const all = new Set();
+    const all = new Set<string>();
     mockedDependencyTree.forEach(deps => {
       deps.forEach(r => all.add(r.name));
     });

packages/metro/src/DeltaBundler/mergeDeltas.js

@@ -20,9 +20,9 @@ function mergeDeltas(delta1: DeltaBundle, delta2: DeltaBundle): DeltaBundle {
   const added2 = new Map(delta2.added);
   const modified2 = new Map(delta2.modified);
   const deleted2 = new Set(delta2.deleted);
-  const added = new Map();
-  const modified = new Map();
-  const deleted = new Set();
+  const added = new Map<number, string>();
+  const modified = new Map<number, string>();
+  const deleted = new Set<number>();
 
   for (const [id, code] of added1) {
     if (!deleted2.has(id) && !modified2.has(id)) {

packages/metro/src/ModuleGraph/node-haste/HasteFS.js

@@ -72,7 +72,7 @@ module.exports = class HasteFS {
 };
 
 function buildDirectorySet(files: Array<string>): Set<string> {
-  const directories = new Set();
+  const directories = new Set<string>();
   files.forEach((path: string) => {
     const parsedPath = parse(path);
     const root = parsedPath.root;
@@ -88,7 +88,7 @@ function buildDirectorySet(files: Array<string>): Set<string> {
 function buildDirectoryEntries(
   files: Array<pathParseResult>,
 ): Map<string, Array<string>> {
-  const directoryEntries = new Map();
+  const directoryEntries = new Map<string, Array<string>>();
   files.forEach(({base, dir}) => {
     const entries = directoryEntries.get(dir);
     if (entries) {

packages/metro/src/ModuleGraph/node-haste/node-haste.js

@@ -91,7 +91,7 @@ const createModuleMap = ({
     (platforms ?? defaults.platforms).concat([NATIVE_PLATFORM]),
   );
 
-  const map = new Map();
+  const map = new Map<string, ModuleMapItem>();
 
   files.forEach((filePath: string) => {
     if (isNodeModules(filePath)) {

packages/metro/src/ModuleGraph/output/multiple-files-ram-bundle.js

@@ -55,7 +55,7 @@ function asMultipleFilesRamBundle({
     .join('\n');
 
   // Write one file per module, wrapped with __d() call if it proceeds.
-  const extraFiles = new Map();
+  const extraFiles = new Map<string, string | Buffer>();
   deferredModules.forEach(deferredModule => {
     extraFiles.set(
       path.join(JS_MODULES, deferredModule.id + '.js'),

packages/metro/src/ModuleGraph/output/util.js

@@ -286,7 +286,7 @@ exports.concat = function* concat<T>(
 // Creates an idempotent function that returns numeric IDs for objects based
 // on their `path` property.
 exports.createIdForPathFn = (): (({path: string, ...}) => number) => {
-  const seen = new Map();
+  const seen = new Map<string, number>();
   let next = 0;
   return ({path}) => {
     let id = seen.get(path);

packages/metro/src/ModuleGraph/worker/collectDependencies.js

@@ -161,7 +161,7 @@ function collectDependencies<TSplitCondition = void>(
   ast: BabelNodeFile,
   options: Options<TSplitCondition>,
 ): CollectedDependencies<TSplitCondition> {
-  const visited = new WeakSet();
+  const visited = new WeakSet<BabelNodeCallExpression>();
 
   const state: State<TSplitCondition> = {
     asyncRequireModulePathStringLiteral: null,

packages/metro/src/Server.js

@@ -1158,7 +1158,7 @@ class Server {
         return frame;
       });
       // In case of multiple bundles / HMR, some stack frames can have different URLs from others
-      const urls = new Set();
+      const urls = new Set<string>();
 
       stack.forEach(frame => {
         const sourceUrl = frame.file;