From 0f7e01d81716399bab56faf290df45289002d007 Mon Sep 17 00:00:00 2001
From: Rob Hogan <2590098+robhogan@users.noreply.github.com>
Date: Wed, 4 Nov 2026 21:11:40 +0000
Subject: [PATCH] Give function type parameters descriptive names

Follow up to https://github.com/react/metro/pull/2169, which named every unnamed parameter in Flow function types `v`, `v<index>` or `rest`. This replaces those placeholders with descriptive names, taken from the implementation or call site wherever there is one.

The only change beyond names is dropping two `void` parameters that are never passed, on `resolve` in `IncrementalBundler` and `cb` in `bundle.flow.js`.

Changelog: Internal

Test plan:
Compiled each changed file outside `flow-typed/` with the repo's Babel config before and after this change, and the output is identical. API snapshots are unchanged.
---
 flow-typed/environment/node.js                | 16 +++----
 flow-typed/fb-watchman.js                     | 12 ++---
 flow-typed/jest-worker.js                     |  2 +-
 flow-typed/jest.js                            |  6 +--
 flow-typed/npm/babel-traverse_v7.x.x.js       |  2 +-
 flow-typed/npm/babel_v7.x.x.js                | 26 +++++------
 flow-typed/npm/ws_v7.x.x.js                   | 45 +++++++++++--------
 packages/buck-worker-tool/src/worker-tool.js  | 14 +++---
 packages/metro-config/src/loadConfig.js       |  4 +-
 packages/metro-core/src/Terminal.js           |  2 +-
 .../crawlers/__tests__/integration-test.js    |  2 +-
 .../crawlers/watchman/__tests__/index-test.js |  4 +-
 packages/metro-file-map/src/flow-types.js     |  6 +--
 packages/metro-file-map/src/index.js          |  4 +-
 .../metro-file-map/src/lib/FileProcessor.js   |  4 +-
 .../src/lib/__tests__/FileProcessor-test.js   |  4 +-
 .../src/lib/__tests__/RootPathUtils-test.js   |  2 +-
 .../src/lib/__tests__/TreeFS-test.js          |  2 +-
 .../metro-file-map/src/plugins/HastePlugin.js |  2 +-
 .../haste/__tests__/HastePlugin-test.js       |  2 +-
 .../mocks/__tests__/MockPlugin-test.js        |  2 +-
 .../src/watchers/FallbackWatcher.js           |  8 ++--
 .../watchers/__tests__/NativeWatcher-test.js  |  8 ++--
 .../__tests__/WatchmanWatcher-test.js         |  4 +-
 .../metro-resolver/src/__tests__/utils.js     |  2 +-
 .../src/modules/__tests__/HMRClient-test.js   |  6 +--
 .../metro-runtime/src/modules/asyncRequire.js |  4 +-
 .../__tests__/MetroFastRefreshMockRuntime.js  |  8 ++--
 .../metro-runtime/src/polyfills/require.js    |  4 +-
 .../metro-source-map/src/Consumer/search.js   |  2 +-
 .../src/generateFunctionMap.js                |  4 +-
 packages/metro-source-map/src/source-map.js   |  2 +-
 .../src/GoogleIgnoreListConsumer.js           |  4 +-
 .../src/SourceMetadataMapConsumer.js          |  4 +-
 packages/metro-transform-plugins/src/index.js |  2 +-
 packages/metro/src/Bundler/util.js            |  2 +-
 .../Serializers/getRamBundleInfo.js           |  4 +-
 .../Serializers/helpers/getSourceMapInfo.js   |  2 +-
 .../DeltaBundler/Serializers/helpers/js.js    |  2 +-
 .../Serializers/helpers/processModules.js     |  2 +-
 .../DeltaBundler/Serializers/hmrJSBundle.js   |  2 +-
 .../Serializers/sourceMapGenerator.js         |  4 +-
 .../metro/src/DeltaBundler/Transformer.js     |  2 +-
 .../metro/src/DeltaBundler/Worker.flow.js     | 12 ++---
 .../src/DeltaBundler/__tests__/Graph-test.js  |  2 +-
 .../src/DeltaBundler/__tests__/test-utils.js  |  2 +-
 .../metro/src/DeltaBundler/buildSubgraph.js   |  5 ++-
 packages/metro/src/DeltaBundler/types.js      |  4 +-
 packages/metro/src/HmrServer.js               |  9 ++--
 packages/metro/src/IncrementalBundler.js      |  2 +-
 .../ModuleGraph/worker/collectDependencies.js |  4 +-
 packages/metro/src/Server.js                  |  4 +-
 packages/metro/src/Server/symbolicate.js      |  4 +-
 .../metro/src/__tests__/HmrServer-test.js     |  4 +-
 packages/metro/src/lib/debounceAsyncQueue.js  | 32 ++++++-------
 packages/metro/src/lib/getAppendScripts.js    |  6 +--
 packages/metro/src/lib/pathUtils.js           |  2 +-
 .../output/RamBundle/as-indexed-file.js       | 12 ++---
 .../metro/src/shared/output/bundle.flow.js    |  4 +-
 private/metro-memory-fs/src/index.js          | 22 ++++-----
 scripts/generateTypeScriptDefinitions.js      |  2 +-
 61 files changed, 201 insertions(+), 176 deletions(-)

diff --git a/flow-typed/environment/node.js b/flow-typed/environment/node.js
index cb70c63a4e..e1bd0da5fd 100644
--- a/flow-typed/environment/node.js
+++ b/flow-typed/environment/node.js
@@ -2549,7 +2549,7 @@ declare module 'fs' {
       ...
     }>,
     writeFile(
-      v0: FSPromisePath | FileHandle,
+      file: FSPromisePath | FileHandle,
       data: string | Buffer | Uint8Array,
       options?: string | WriteOptions,
     ): Promise<void>,
@@ -3343,9 +3343,9 @@ declare module 'perf_hooks' {
     setResourceTimingBufferSize(maxSize: number): void;
     readonly timeOrigin: number;
     timerify<TArgs extends Iterable<unknown>, TReturn>(
-      fn: (...rest: TArgs) => TReturn,
+      fn: (...args: TArgs) => TReturn,
       options?: Readonly<{histogram?: RecordableHistogram}>,
-    ): (...rest: TArgs) => TReturn;
+    ): (...args: TArgs) => TReturn;
     toJSON(): unknown;
   }
 
@@ -3537,7 +3537,7 @@ type readline$InterfaceCompleter = (
   | [Array<string>, string]
   | ((
       line: string,
-      v1: (err: ?Error, data: [Array<string>, string]) => void,
+      callback: (err: ?Error, data: [Array<string>, string]) => void,
     ) => void);
 
 declare class readline$Interface extends events$EventEmitter {
@@ -5630,18 +5630,18 @@ declare class Process extends events$EventEmitter {
   emitWarning(warning: string | Error): void;
   emitWarning(
     warning: string,
-    typeOrCtor: string | ((...rest: empty) => unknown),
+    typeOrCtor: string | ((...args: empty) => unknown),
   ): void;
   emitWarning(
     warning: string,
     type: string,
-    codeOrCtor: string | ((...rest: empty) => unknown),
+    codeOrCtor: string | ((...args: empty) => unknown),
   ): void;
   emitWarning(
     warning: string,
     type: string,
     code: string,
-    ctor?: (...rest: empty) => unknown,
+    ctor?: (...args: empty) => unknown,
   ): void;
   execArgv: Array<string>;
   execPath: string;
@@ -5671,7 +5671,7 @@ declare class Process extends events$EventEmitter {
     },
     rss: () => number,
   };
-  nextTick: <T>(cb: (...rest: T) => unknown, ...rest: T) => void;
+  nextTick: <T>(cb: (...args: T) => unknown, ...args: T) => void;
   pid: number;
   platform: string;
   release: {
diff --git a/flow-typed/fb-watchman.js b/flow-typed/fb-watchman.js
index 209ada0e26..2cd56cfb17 100644
--- a/flow-typed/fb-watchman.js
+++ b/flow-typed/fb-watchman.js
@@ -235,14 +235,14 @@ declare module 'fb-watchman' {
     ): void;
     end(): void;
 
-    on(v0: 'connect', v1: () => void): void;
-    on(v0: 'end', v1: () => void): void;
-    on(v0: 'error', v1: (error: Error) => void): void;
+    on(event: 'connect', listener: () => void): void;
+    on(event: 'end', listener: () => void): void;
+    on(event: 'error', listener: (error: Error) => void): void;
     on(
-      v0: 'subscription',
-      v1: (event: WatchmanSubscriptionEvent) => void,
+      event: 'subscription',
+      listener: (event: WatchmanSubscriptionEvent) => void,
     ): void;
-    on(v0: 'log', v1: (event: WatchmanLogEvent) => void): void;
+    on(event: 'log', listener: (event: WatchmanLogEvent) => void): void;
     removeAllListeners: (eventName?: string) => void;
   }
 
diff --git a/flow-typed/jest-worker.js b/flow-typed/jest-worker.js
index 86f0e4a682..cdbb8d8a72 100644
--- a/flow-typed/jest-worker.js
+++ b/flow-typed/jest-worker.js
@@ -263,7 +263,7 @@ declare module 'jest-worker' {
 
   declare export class Worker<
     TExposed extends Readonly<{
-      [string]: (...rest: Array<$FlowFixMe>) => Promise<$FlowFixMe>,
+      [string]: (...args: Array<$FlowFixMe>) => Promise<$FlowFixMe>,
     }> = {},
     TSetupArgs extends ReadonlyArray<unknown> = ReadonlyArray<unknown>,
   > {
diff --git a/flow-typed/jest.js b/flow-typed/jest.js
index 41eb31eeaf..d07660caea 100644
--- a/flow-typed/jest.js
+++ b/flow-typed/jest.js
@@ -1191,9 +1191,9 @@ type JestPrettyFormatColors = {
   ...
 };
 
-type JestPrettyFormatIndent = (v: string) => string;
+type JestPrettyFormatIndent = (str: string) => string;
 type JestPrettyFormatRefs = Array<any>;
-type JestPrettyFormatPrint = (v: any) => string;
+type JestPrettyFormatPrint = (val: any) => string;
 type JestPrettyFormatStringOrNull = string | null;
 
 type JestPrettyFormatOptions = {|
@@ -1224,7 +1224,7 @@ type JestPrettyFormatPlugin = {
     opts: JestPrettyFormatOptions,
     colors: JestPrettyFormatColors,
   ) => string,
-  test: (v: any) => boolean,
+  test: (val: any) => boolean,
   ...
 };
 
diff --git a/flow-typed/npm/babel-traverse_v7.x.x.js b/flow-typed/npm/babel-traverse_v7.x.x.js
index 93dbe352d2..c5988473f3 100644
--- a/flow-typed/npm/babel-traverse_v7.x.x.js
+++ b/flow-typed/npm/babel-traverse_v7.x.x.js
@@ -631,7 +631,7 @@ declare module '@babel/traverse' {
 
     constructor(hub: HubInterface, parent: BabelNode): NodePath<TNode>;
 
-    static get(v: {
+    static get(options: {
       hub: HubInterface,
       parentPath: ?NodePath<>,
       parent: BabelNode,
diff --git a/flow-typed/npm/babel_v7.x.x.js b/flow-typed/npm/babel_v7.x.x.js
index c3a6e73508..d15984eaa0 100644
--- a/flow-typed/npm/babel_v7.x.x.js
+++ b/flow-typed/npm/babel_v7.x.x.js
@@ -387,7 +387,7 @@ declare module '@babel/core' {
     buildCodeFrameError<TError extends Error>(
       node: BabelNode,
       msg: string,
-      v2: Class<TError>,
+      Error: Class<TError>,
     ): TError;
 
     mergeSourceMap(map: _BabelSourceMap): _BabelSourceMap;
@@ -408,7 +408,7 @@ declare module '@babel/core' {
 
     parseShebang(): void;
 
-    makeResult<T>(v: TransformResult<T>): TransformResult<T>;
+    makeResult<T>(result: TransformResult<T>): TransformResult<T>;
 
     generate(): TransformResult<>;
   }
@@ -955,8 +955,8 @@ declare module '@babel/core' {
   |};
 
   declare type TransformCallback<TMetadata> =
-    | ((v0: Error, v1: null) => unknown)
-    | ((v0: null, v1: TransformResult<TMetadata> | null) => unknown);
+    | ((error: Error, result: null) => unknown)
+    | ((error: null, result: TransformResult<TMetadata> | null) => unknown);
 
   /**
    * Transforms the passed in code. Calling a callback with an object with the generated code, source map, and AST.
@@ -1043,7 +1043,7 @@ declare module '@babel/core' {
     code: string,
     options?: BabelCoreOptions,
     callback:
-      ((error: Error) => void) | ((v0: void, v1: BabelNodeFile) => void),
+      ((error: Error) => void) | ((error: void, ast: BabelNodeFile) => void),
   ): void;
 
   declare export function parseSync(
@@ -1097,8 +1097,8 @@ declare module '@babel/core' {
   declare export function loadOptions(
     options?: unknown,
     callback:
-      | ((error: Error, v1: null) => unknown)
-      | ((v0: null, config: ResolvedConfig | null) => unknown),
+      | ((error: Error, config: null) => unknown)
+      | ((error: null, config: ResolvedConfig | null) => unknown),
   ): void;
   declare export function loadOptionsSync(
     options?: unknown,
@@ -1126,8 +1126,8 @@ declare module '@babel/core' {
   declare export function loadPartialConfig(
     options?: unknown,
     callback:
-      | ((error: Error, v1: null) => unknown)
-      | ((v0: null, config: PartialConfig | null) => unknown),
+      | ((error: Error, config: null) => unknown)
+      | ((error: null, config: PartialConfig | null) => unknown),
   ): void;
   declare export function loadPartialConfigSync(
     options?: unknown,
@@ -1315,13 +1315,13 @@ declare module '@babel/template' {
     (opts: PublicOpts): TemplateBuilder<T>,
 
     // Building from a string produces an AST builder function by default.
-    (tpl: string, opts: ?PublicOpts): (v: ?PublicReplacements) => T,
+    (tpl: string, opts: ?PublicOpts): (replacements: ?PublicReplacements) => T,
 
     // Building from a template literal produces an AST builder function by default.
     (
       tpl: Array<string>,
       ...args: Array<unknown>
-    ): (v: ?PublicReplacements) => T,
+    ): (replacements: ?PublicReplacements) => T,
 
     // Allow users to explicitly create templates that produce ASTs, skipping
     // the need for an intermediate function.
@@ -1354,13 +1354,13 @@ declare module '@babel/template' {
     (
       tpl: string,
       opts: ?PublicOpts,
-    ): (v: ?PublicReplacements) => Statement | Array<Statement>,
+    ): (replacements: ?PublicReplacements) => Statement | Array<Statement>,
 
     // Building from a template literal produces an AST builder function by default.
     (
       tpl: Array<string>,
       ...args: Array<unknown>
-    ): (v: ?PublicReplacements) => Statement | Array<Statement>,
+    ): (replacements: ?PublicReplacements) => Statement | Array<Statement>,
 
     // Allow users to explicitly create templates that produce ASTs, skipping
     // the need for an intermediate function.
diff --git a/flow-typed/npm/ws_v7.x.x.js b/flow-typed/npm/ws_v7.x.x.js
index 4dc479b4fd..32ef350263 100644
--- a/flow-typed/npm/ws_v7.x.x.js
+++ b/flow-typed/npm/ws_v7.x.x.js
@@ -47,20 +47,23 @@ declare class ws$WebSocketServer extends events$EventEmitter {
   /**
    * Emitted when the server closes.
    */
-  on(event: 'close', v1: () => unknown): this;
+  on(event: 'close', listener: () => unknown): this;
 
   /**
    * Emitted when the handshake is complete.
    */
   on(
     event: 'connection',
-    v1: (socket: ws$WebSocket, request: http$IncomingMessage<>) => unknown,
+    listener: (
+      socket: ws$WebSocket,
+      request: http$IncomingMessage<>,
+    ) => unknown,
   ): this;
 
   /**
    * Emitted when an error occurs on the underlying server.
    */
-  on(event: 'error', v1: (error: Error) => unknown): this;
+  on(event: 'error', listener: (error: Error) => unknown): this;
 
   /**
    * Emitted before the response headers are written to the socket as part of
@@ -68,13 +71,16 @@ declare class ws$WebSocketServer extends events$EventEmitter {
    */
   on(
     event: 'headers',
-    v1: (headers: Array<string>, request: http$IncomingMessage<>) => unknown,
+    listener: (
+      headers: Array<string>,
+      request: http$IncomingMessage<>,
+    ) => unknown,
   ): this;
 
   /**
    * Emitted when the underlying server has been bound.
    */
-  on(event: 'listening', v1: () => unknown): this;
+  on(event: 'listening', listener: () => unknown): this;
 
   /**
    * Returns the bound address, the address family name, and port of the server
@@ -102,7 +108,7 @@ declare class ws$WebSocketServer extends events$EventEmitter {
     request: http$IncomingMessage<>,
     socket: net$Socket,
     head: Buffer,
-    callback: (v: ?ws$WebSocket) => unknown,
+    callback: (socket: ?ws$WebSocket) => unknown,
   ): void;
 
   /**
@@ -137,8 +143,8 @@ declare type ws$MessageListener = (
   isBinary: boolean,
 ) => unknown;
 declare type ws$OpenListener = () => unknown;
-declare type ws$PingListener = (v: Buffer) => unknown;
-declare type ws$PongListener = (v: Buffer) => unknown;
+declare type ws$PingListener = (data: Buffer) => unknown;
+declare type ws$PongListener = (data: Buffer) => unknown;
 declare type ws$UnexpectedResponseListener = (
   request: http$ClientRequest<>,
   response: http$IncomingMessage<>,
@@ -173,44 +179,47 @@ declare class ws$WebSocket extends events$EventEmitter {
   /*
    * Emitted when the connection is closed.
    */
-  on(v0: 'close', v1: ws$CloseListener): this;
+  on(event: 'close', listener: ws$CloseListener): this;
 
   /*
    * Emitted when an error occurs.
    */
-  on(v0: 'error', v1: ws$ErrorListener): this;
+  on(event: 'error', listener: ws$ErrorListener): this;
 
   /*
    * Emitted when a message is received from the server.
    */
-  on(v0: 'message', v1: ws$MessageListener): this;
+  on(event: 'message', listener: ws$MessageListener): this;
 
   /*
    * Emitted when the connection is established.
    */
-  on(v0: 'open', v1: ws$OpenListener): this;
+  on(event: 'open', listener: ws$OpenListener): this;
 
   /*
    * Emitted when a ping is received from the server.
    */
-  on(v0: 'ping', v1: ws$PingListener): this;
+  on(event: 'ping', listener: ws$PingListener): this;
 
   /*
    * Emitted when a pong is received from the server.
    */
-  on(v0: 'pong', v1: ws$PongListener): this;
+  on(event: 'pong', listener: ws$PongListener): this;
 
   /*
    * Emitted when the server response is not the expected one,
    * for example a 401 response.
    */
-  on(v0: 'unexpected-response', v1: ws$UnexpectedResponseListener): this;
+  on(
+    event: 'unexpected-response',
+    listener: ws$UnexpectedResponseListener,
+  ): this;
 
   /*
    * Emitted when response headers are received from the server as part of the
    * handshake.
    */
-  on(v0: 'upgrade', v1: ws$UpgradeListener): this;
+  on(event: 'upgrade', listener: ws$UpgradeListener): this;
 
   /**
    * Register an event listener emulating the `EventTarget` interface.
@@ -247,7 +256,7 @@ declare class ws$WebSocket extends events$EventEmitter {
   ): this;
   addEventListener(
     type: 'unexpected-response',
-    v1: ws$UnexpectedResponseListener,
+    listener: ws$UnexpectedResponseListener,
     options?: {once?: boolean},
   ): this;
   addEventListener(
@@ -313,7 +322,7 @@ declare class ws$WebSocket extends events$EventEmitter {
   removeEventListener(type: 'pong', listener: ws$PongListener): this;
   removeEventListener(
     type: 'unexpected-response',
-    v1: ws$UnexpectedResponseListener,
+    listener: ws$UnexpectedResponseListener,
   ): this;
   removeEventListener(type: 'upgrade', listener: ws$UpgradeListener): this;
 
diff --git a/packages/buck-worker-tool/src/worker-tool.js b/packages/buck-worker-tool/src/worker-tool.js
index 9212c23c1a..034332e00d 100644
--- a/packages/buck-worker-tool/src/worker-tool.js
+++ b/packages/buck-worker-tool/src/worker-tool.js
@@ -67,20 +67,20 @@ type IncomingMessage = HandshakeMessage | CommandMessage;
 type Response = HandshakeResponse | CommandResponse | ErrorResponse;
 type RespondFn = (response: Response) => void;
 
-type JSONReaderDataHandler = (v: IncomingMessage) => unknown;
+type JSONReaderDataHandler = (message: IncomingMessage) => unknown;
 type JSONReaderEndHandler = () => unknown;
 
 type JSONReaderDataListener = (
-  v0: 'data',
-  v1: JSONReaderDataHandler,
+  event: 'data',
+  handler: JSONReaderDataHandler,
 ) => JSONReader;
 type JSONReaderEndListener = (
-  v0: 'end',
-  v1: JSONReaderEndHandler,
+  event: 'end',
+  handler: JSONReaderEndHandler,
 ) => JSONReader;
 type JSONReaderRootEndListener = (
-  v0: 'root_end',
-  v1: JSONReaderEndHandler,
+  event: 'root_end',
+  handler: JSONReaderEndHandler,
 ) => JSONReader;
 type JSONReaderListener = JSONReaderDataListener &
   JSONReaderEndListener &
diff --git a/packages/metro-config/src/loadConfig.js b/packages/metro-config/src/loadConfig.js
index 03024d0285..7749eba6f5 100644
--- a/packages/metro-config/src/loadConfig.js
+++ b/packages/metro-config/src/loadConfig.js
@@ -246,7 +246,9 @@ function concatUnique<T>(
 async function mergeConfigAsync<T extends InputConfigT>(
   baseConfig: Promise<T>,
   ...reversedConfigs: ReadonlyArray<
-    InputConfigT | ((v: T) => InputConfigT) | ((v: T) => Promise<InputConfigT>),
+    | InputConfigT
+    | ((baseConfig: T) => InputConfigT)
+    | ((baseConfig: T) => Promise<InputConfigT>),
   >
 ): Promise<T> {
   let currentConfig: T = await baseConfig;
diff --git a/packages/metro-core/src/Terminal.js b/packages/metro-core/src/Terminal.js
index e6402ad90c..5ef2e0b6d7 100644
--- a/packages/metro-core/src/Terminal.js
+++ b/packages/metro-core/src/Terminal.js
@@ -104,7 +104,7 @@ export default class Terminal {
   #isUpdating: boolean;
   #hasPendingUpdate: boolean;
   #isFlushRequested: boolean;
-  #writeNonTTYStatusThrottled: (v: string) => void;
+  #writeNonTTYStatusThrottled: (status: string) => void;
   #bytesWrittenAfterStatus: ?number;
 
   constructor(stream: UnderlyingStream, opts: {ttyPrint?: boolean} = {}) {
diff --git a/packages/metro-file-map/src/crawlers/__tests__/integration-test.js b/packages/metro-file-map/src/crawlers/__tests__/integration-test.js
index fc937e6386..58bfe529bc 100644
--- a/packages/metro-file-map/src/crawlers/__tests__/integration-test.js
+++ b/packages/metro-file-map/src/crawlers/__tests__/integration-test.js
@@ -54,7 +54,7 @@ declare var expect: {
   extend(matchers: {[name: string]: JestMatcher, ...}): void,
   assertions(expectedAssertions: number): void,
   any(value: unknown): JestAsymmetricEqualityType,
-  oneOf: (v0: unknown, v1: unknown) => boolean,
+  oneOf: (first: unknown, second: unknown) => boolean,
   ...
 };
 
diff --git a/packages/metro-file-map/src/crawlers/watchman/__tests__/index-test.js b/packages/metro-file-map/src/crawlers/watchman/__tests__/index-test.js
index 80e030bd6c..a035fe5b2b 100644
--- a/packages/metro-file-map/src/crawlers/watchman/__tests__/index-test.js
+++ b/packages/metro-file-map/src/crawlers/watchman/__tests__/index-test.js
@@ -28,11 +28,11 @@ jest.mock('fb-watchman', () => ({
 }));
 
 // /some/path on posix, c:\some\path on Windows
-const systemPath: (v: string) => string = filePath =>
+const systemPath: (filePath: string) => string = filePath =>
   watchmanPath(filePath).replace(/\//g, path.sep);
 
 // /some/path on posix, c:/some/path on Windows. Relative unchanged.
-const watchmanPath: (v: string) => string = filePath =>
+const watchmanPath: (filePath: string) => string = filePath =>
   filePath.replace(/^\//, 'C:/');
 
 const DEFAULT_OPTIONS: CrawlerOptions = {
diff --git a/packages/metro-file-map/src/flow-types.js b/packages/metro-file-map/src/flow-types.js
index cdd7eebb4c..633a328bf3 100644
--- a/packages/metro-file-map/src/flow-types.js
+++ b/packages/metro-file-map/src/flow-types.js
@@ -277,7 +277,7 @@ export type FileMapPluginWorker = Readonly<{
    * This applies to files under node_modules too, which a plugin may reject
    * using `isNodeModules`.
    */
-  filter: (v: {normalPath: string, isNodeModules: boolean}) => boolean,
+  filter: (file: {normalPath: string, isNodeModules: boolean}) => boolean,
   /**
    * If true, the worker is not run on files as they are crawled or changed,
    * and `filter` is not consulted. It runs only on the files the plugin asks
@@ -316,8 +316,8 @@ export type InputFileMapPlugin = FileMapPlugin<empty, empty>;
 
 export interface MetadataWorker {
   processFile(
-    v0: WorkerMessage,
-    v1: Readonly<{getContent: () => Buffer}>,
+    data: WorkerMessage,
+    utils: Readonly<{getContent: () => Buffer}>,
   ): V8Serializable;
 }
 
diff --git a/packages/metro-file-map/src/index.js b/packages/metro-file-map/src/index.js
index 8812ca6c30..f0132e8457 100644
--- a/packages/metro-file-map/src/index.js
+++ b/packages/metro-file-map/src/index.js
@@ -1325,8 +1325,8 @@ const toPublicMetadata = (
 
 // TODO: Replace with it.map() from Node 22+
 const mapIterable: <T, S>(
-  v0: Iterable<T>,
-  v1: (v: T) => S,
+  it: Iterable<T>,
+  fn: (item: T) => S,
 ) => IteratorObject<S> = (it, fn) =>
   (function* mapped() {
     for (const item of it) {
diff --git a/packages/metro-file-map/src/lib/FileProcessor.js b/packages/metro-file-map/src/lib/FileProcessor.js
index e5133d4319..a61a19f8bf 100644
--- a/packages/metro-file-map/src/lib/FileProcessor.js
+++ b/packages/metro-file-map/src/lib/FileProcessor.js
@@ -41,7 +41,7 @@ type ProcessFileRequest = Readonly<{
 }>;
 
 interface AsyncWorker {
-  readonly processFile: (v: WorkerMessage) => Promise<WorkerMetadata>;
+  readonly processFile: (message: WorkerMessage) => Promise<WorkerMetadata>;
   readonly end: () => Promise<void>;
 }
 
@@ -237,7 +237,7 @@ export class FileProcessor {
     debug('Creating worker farm of %d worker threads', numWorkers);
     this.#perfLogger?.point('initWorkers_start');
     const jestWorker = new JestWorker<{
-      processFile: (v: WorkerMessage) => Promise<WorkerMetadata>,
+      processFile: (message: WorkerMessage) => Promise<WorkerMetadata>,
     }>(workerPath, {
       exposedMethods: ['processFile'],
       maxRetries: 3,
diff --git a/packages/metro-file-map/src/lib/__tests__/FileProcessor-test.js b/packages/metro-file-map/src/lib/__tests__/FileProcessor-test.js
index c0e21100fe..f1c9582717 100644
--- a/packages/metro-file-map/src/lib/__tests__/FileProcessor-test.js
+++ b/packages/metro-file-map/src/lib/__tests__/FileProcessor-test.js
@@ -29,7 +29,7 @@ const mockWorkerFn = jest.fn().mockReturnValue({});
 
 // Convenience function to write paths with posix separators but convert them
 // to system separators
-const p: (v: string) => string = filePath =>
+const p: (filePath: string) => string = filePath =>
   process.platform === 'win32'
     ? filePath.replace(/\//g, '\\').replace(/^\\/, 'C:\\')
     : filePath;
@@ -54,7 +54,7 @@ describe('processBatch', () => {
       setup: () => {},
       processFile: mockWorkerFn,
       Worker: class {
-        processFile: (v: WorkerMessage) => WorkerMetadata = mockWorkerFn;
+        processFile: (message: WorkerMessage) => WorkerMetadata = mockWorkerFn;
       },
     }));
     FileProcessor = require('../FileProcessor').FileProcessor;
diff --git a/packages/metro-file-map/src/lib/__tests__/RootPathUtils-test.js b/packages/metro-file-map/src/lib/__tests__/RootPathUtils-test.js
index e20667f4f3..d489c22063 100644
--- a/packages/metro-file-map/src/lib/__tests__/RootPathUtils-test.js
+++ b/packages/metro-file-map/src/lib/__tests__/RootPathUtils-test.js
@@ -17,7 +17,7 @@ jest.mock('node:path', () => mockPathModule);
 describe.each([['win32'], ['posix']])('RootPathUtils on %s', platform => {
   // Convenience function to write paths with posix separators but convert them
   // to system separators
-  const p: (v: string) => string = filePath =>
+  const p: (filePath: string) => string = filePath =>
     platform === 'win32'
       ? filePath.replace(/\//g, '\\').replace(/^\\/, 'C:\\')
       : filePath;
diff --git a/packages/metro-file-map/src/lib/__tests__/TreeFS-test.js b/packages/metro-file-map/src/lib/__tests__/TreeFS-test.js
index 356aab4f10..1e90ebbf79 100644
--- a/packages/metro-file-map/src/lib/__tests__/TreeFS-test.js
+++ b/packages/metro-file-map/src/lib/__tests__/TreeFS-test.js
@@ -31,7 +31,7 @@ jest.mock('node:path', () => mockPathModule);
 describe.each([['win32'], ['posix']])('TreeFS on %s', platform => {
   // Convenience function to write paths with posix separators but convert them
   // to system separators
-  const p: (v: string) => string = filePath =>
+  const p: (filePath: string) => string = filePath =>
     platform === 'win32'
       ? filePath.replace(/\//g, '\\').replace(/^\\/, 'C:\\')
       : filePath;
diff --git a/packages/metro-file-map/src/plugins/HastePlugin.js b/packages/metro-file-map/src/plugins/HastePlugin.js
index 24d76f0c65..6baed05b50 100644
--- a/packages/metro-file-map/src/plugins/HastePlugin.js
+++ b/packages/metro-file-map/src/plugins/HastePlugin.js
@@ -61,7 +61,7 @@ export default class HastePlugin
   readonly #duplicates: DuplicatesIndex = new Map();
   readonly #enableHastePackages: boolean;
   readonly #failValidationOnConflicts: boolean;
-  #getModuleNameByPath: (v: string) => ?string;
+  #getModuleNameByPath: (mixedPath: string) => ?string;
   readonly #hasteImplModulePath: ?string;
   readonly #map: Map<string, HasteMapItem> = new Map();
   readonly #pathUtils: RootPathUtils;
diff --git a/packages/metro-file-map/src/plugins/haste/__tests__/HastePlugin-test.js b/packages/metro-file-map/src/plugins/haste/__tests__/HastePlugin-test.js
index 90edd2e3a9..00421797d7 100644
--- a/packages/metro-file-map/src/plugins/haste/__tests__/HastePlugin-test.js
+++ b/packages/metro-file-map/src/plugins/haste/__tests__/HastePlugin-test.js
@@ -19,7 +19,7 @@ let mockPathModule;
 jest.mock('node:path', () => mockPathModule);
 
 describe.each([['win32'], ['posix']])('HastePlugin on %s', platform => {
-  const p: (v: string) => string = filePath =>
+  const p: (filePath: string) => string = filePath =>
     platform === 'win32'
       ? filePath.replace(/\//g, '\\').replace(/^\\/, 'C:\\')
       : filePath;
diff --git a/packages/metro-file-map/src/plugins/mocks/__tests__/MockPlugin-test.js b/packages/metro-file-map/src/plugins/mocks/__tests__/MockPlugin-test.js
index 6bbc3f0787..97701b17e1 100644
--- a/packages/metro-file-map/src/plugins/mocks/__tests__/MockPlugin-test.js
+++ b/packages/metro-file-map/src/plugins/mocks/__tests__/MockPlugin-test.js
@@ -15,7 +15,7 @@ let mockPathModule;
 jest.mock('node:path', () => mockPathModule);
 
 describe.each([['win32'], ['posix']])('MockPlugin on %s', platform => {
-  const p: (v: string) => string = filePath =>
+  const p: (filePath: string) => string = filePath =>
     platform === 'win32'
       ? filePath.replace(/\//g, '\\').replace(/^\\/, 'C:\\')
       : filePath;
diff --git a/packages/metro-file-map/src/watchers/FallbackWatcher.js b/packages/metro-file-map/src/watchers/FallbackWatcher.js
index 47fc5d8c18..eac161e2ea 100644
--- a/packages/metro-file-map/src/watchers/FallbackWatcher.js
+++ b/packages/metro-file-map/src/watchers/FallbackWatcher.js
@@ -499,10 +499,10 @@ function isIgnorableFileError(error: Error | {code: string}) {
  */
 async function recReaddir(
   root: string,
-  dirCallback: (v0: string, v1: Stats) => void,
-  fileCallback: (v0: string, v1: Stats) => void,
-  symlinkCallback: (v0: string, v1: Stats) => void,
-  errorCallback: (v: Error) => void,
+  dirCallback: (dirPath: string, stats: Stats) => void,
+  fileCallback: (filePath: string, stats: Stats) => void,
+  symlinkCallback: (symlinkPath: string, stats: Stats) => void,
+  errorCallback: (error: Error) => void,
   ignored: ?RegExp,
 ): Promise<void> {
   const pending = [root];
diff --git a/packages/metro-file-map/src/watchers/__tests__/NativeWatcher-test.js b/packages/metro-file-map/src/watchers/__tests__/NativeWatcher-test.js
index 7365812c7f..7d5683f899 100644
--- a/packages/metro-file-map/src/watchers/__tests__/NativeWatcher-test.js
+++ b/packages/metro-file-map/src/watchers/__tests__/NativeWatcher-test.js
@@ -24,13 +24,13 @@ const ROOT = resolve('/', 'project');
 
 type Deferred<T> = {
   promise: Promise<T>,
-  resolve: (v: T) => void,
-  reject: (v: Error) => void,
+  resolve: (value: T) => void,
+  reject: (error: Error) => void,
 };
 
 function deferred<T>(): Deferred<T> {
-  let resolve: (v: T) => void = () => {};
-  let reject: (v: Error) => void = () => {};
+  let resolve: (value: T) => void = () => {};
+  let reject: (error: Error) => void = () => {};
   const promise = new Promise<T>((res, rej) => {
     resolve = res;
     reject = rej;
diff --git a/packages/metro-file-map/src/watchers/__tests__/WatchmanWatcher-test.js b/packages/metro-file-map/src/watchers/__tests__/WatchmanWatcher-test.js
index 7850e1f89d..63a0e9b90f 100644
--- a/packages/metro-file-map/src/watchers/__tests__/WatchmanWatcher-test.js
+++ b/packages/metro-file-map/src/watchers/__tests__/WatchmanWatcher-test.js
@@ -31,7 +31,7 @@ const cmdCallback = <T>(err: ?Error, result: Partial<T>): void => {
 // Convenience function to write paths with posix separators but convert them
 // to system separators, and prepend a mock drive letter to absolute paths on
 // Windows.
-const p: (v: string) => string = filePath =>
+const p: (filePath: string) => string = filePath =>
   process.platform === 'win32'
     ? filePath.replaceAll('/', '\\').replace(/^\\/, 'C:\\')
     : filePath;
@@ -39,7 +39,7 @@ const p: (v: string) => string = filePath =>
 // Format a posix path as a Watchman-native path on the current platform, i.e.,
 // on Windows, drive letters on absolute paths, but posix-style separators.
 // This should be used for mocking Watchman *output*.
-const wp: (v: string) => string = filePath =>
+const wp: (filePath: string) => string = filePath =>
   process.platform === 'win32' ? filePath.replace(/^\//, 'C:/') : filePath;
 
 jest.mock('fb-watchman', () => ({
diff --git a/packages/metro-resolver/src/__tests__/utils.js b/packages/metro-resolver/src/__tests__/utils.js
index 9a19328d2a..5615d24472 100644
--- a/packages/metro-resolver/src/__tests__/utils.js
+++ b/packages/metro-resolver/src/__tests__/utils.js
@@ -160,7 +160,7 @@ export function createPackageAccessors(
   };
 }
 
-export const posixToSystemPath: (v: string) => string =
+export const posixToSystemPath: (filePath: string) => string =
   process.platform === 'win32'
     ? filePath => filePath.replaceAll('/', '\\').replace(/^\\/, 'C:\\')
     : filePath => filePath;
diff --git a/packages/metro-runtime/src/modules/__tests__/HMRClient-test.js b/packages/metro-runtime/src/modules/__tests__/HMRClient-test.js
index 76643c8f05..84d18ab041 100644
--- a/packages/metro-runtime/src/modules/__tests__/HMRClient-test.js
+++ b/packages/metro-runtime/src/modules/__tests__/HMRClient-test.js
@@ -17,10 +17,10 @@ const HMRClient = require('../HMRClient');
 
 let mockSocket: ?{
   onclose: () => void,
-  onmessage: (v: {data: string}) => void,
-  onerror: (v: {data: string}) => void,
+  onmessage: (event: {data: string}) => void,
+  onerror: (event: {data: string}) => void,
   close: () => void,
-  mockEmit: (v0: string, v1: {data: string}) => void,
+  mockEmit: (type: string, event: {data: string}) => void,
 } = null;
 let evaledCode = '';
 
diff --git a/packages/metro-runtime/src/modules/asyncRequire.js b/packages/metro-runtime/src/modules/asyncRequire.js
index ae1a568797..c7ef012543 100644
--- a/packages/metro-runtime/src/modules/asyncRequire.js
+++ b/packages/metro-runtime/src/modules/asyncRequire.js
@@ -10,8 +10,8 @@
  */
 
 type MetroRequire = {
-  (v: number): unknown,
-  importAll: <T>(v: number) => T,
+  (moduleID: number): unknown,
+  importAll: <T>(moduleID: number) => T,
   ...
 };
 
diff --git a/packages/metro-runtime/src/polyfills/__tests__/MetroFastRefreshMockRuntime.js b/packages/metro-runtime/src/polyfills/__tests__/MetroFastRefreshMockRuntime.js
index 23b71c088a..dd6df4f2a5 100644
--- a/packages/metro-runtime/src/polyfills/__tests__/MetroFastRefreshMockRuntime.js
+++ b/packages/metro-runtime/src/polyfills/__tests__/MetroFastRefreshMockRuntime.js
@@ -198,10 +198,10 @@ const moduleSystemCode = (() => {
 // instead of `__ReactRefresh.performFullRefresh`.
 const createModuleSystem: (
   this: any,
-  v0: RuntimeGlobal,
-  v1: boolean,
-  v2: string,
-  v3: void,
+  global: RuntimeGlobal,
+  __DEV__: boolean,
+  __METRO_GLOBAL_PREFIX__: string,
+  window: void,
 ) => unknown =
   // eslint-disable-next-line no-new-func
   new Function(
diff --git a/packages/metro-runtime/src/polyfills/require.js b/packages/metro-runtime/src/polyfills/require.js
index 2da9533949..facd886012 100644
--- a/packages/metro-runtime/src/polyfills/require.js
+++ b/packages/metro-runtime/src/polyfills/require.js
@@ -839,8 +839,8 @@ if (__DEV__) {
 
   const topologicalSort = function <T>(
     roots: Array<T>,
-    getEdges: (v: T) => Array<T>,
-    earlyStop: (v: T) => boolean,
+    getEdges: (node: T) => Array<T>,
+    earlyStop: (node: T) => boolean,
   ): Array<T> {
     const result = [];
     const visited = new Set<unknown>();
diff --git a/packages/metro-source-map/src/Consumer/search.js b/packages/metro-source-map/src/Consumer/search.js
index 6fc57fda2a..7561ecbad1 100644
--- a/packages/metro-source-map/src/Consumer/search.js
+++ b/packages/metro-source-map/src/Consumer/search.js
@@ -12,7 +12,7 @@
 export function greatestLowerBound<T, U>(
   elements: ReadonlyArray<T>,
   target: U,
-  comparator: (v0: U, v1: T) => number,
+  comparator: (target: U, element: T) => number,
 ): ?number {
   let first = 0;
   let it = 0;
diff --git a/packages/metro-source-map/src/generateFunctionMap.js b/packages/metro-source-map/src/generateFunctionMap.js
index 9f3089f05c..4c065435c9 100644
--- a/packages/metro-source-map/src/generateFunctionMap.js
+++ b/packages/metro-source-map/src/generateFunctionMap.js
@@ -159,7 +159,7 @@ function functionMapBabelPlugin(): PluginObj<> {
 
 function getFunctionMapVisitor(
   context: ?Context,
-  pushMapping: (v: RangeMapping) => void,
+  pushMapping: (mapping: RangeMapping) => void,
 ): FunctionMapVisitor {
   const nameStack: Array<{loc: BabelNodeSourceLocation, name: string}> = [];
   let tailPos = {line: 1, column: 0};
@@ -223,7 +223,7 @@ function getFunctionMapVisitor(
 function forEachMapping(
   ast: BabelNode,
   context: ?Context,
-  pushMapping: (v: RangeMapping) => void,
+  pushMapping: (mapping: RangeMapping) => void,
 ) {
   const visitor = getFunctionMapVisitor(context, pushMapping);
 
diff --git a/packages/metro-source-map/src/source-map.js b/packages/metro-source-map/src/source-map.js
index 7f911f73ae..457b7f7527 100644
--- a/packages/metro-source-map/src/source-map.js
+++ b/packages/metro-source-map/src/source-map.js
@@ -187,7 +187,7 @@ function isVlqMap(
 
 function fromRawMappingsImpl(
   isBlocking: boolean,
-  onDone: (v: Generator) => void,
+  onDone: (generator: Generator) => void,
   modules: ReadonlyArray<RawMappingsModule>,
   offsetLines: number,
 ): void {
diff --git a/packages/metro-symbolicate/src/GoogleIgnoreListConsumer.js b/packages/metro-symbolicate/src/GoogleIgnoreListConsumer.js
index 67c4ec6b0a..b638846f87 100644
--- a/packages/metro-symbolicate/src/GoogleIgnoreListConsumer.js
+++ b/packages/metro-symbolicate/src/GoogleIgnoreListConsumer.js
@@ -14,8 +14,8 @@ import type {BasicSourceMap, IndexMap, MixedSourceMap} from 'metro-source-map';
 import {normalizeSourcePath} from 'metro-source-map';
 
 type SourceNameNormalizer = (
-  v0: string,
-  v1: {readonly sourceRoot?: ?string, ...},
+  sourceInput: string,
+  map: {readonly sourceRoot?: ?string, ...},
 ) => string;
 
 /**
diff --git a/packages/metro-symbolicate/src/SourceMetadataMapConsumer.js b/packages/metro-symbolicate/src/SourceMetadataMapConsumer.js
index cda9a04f93..ded7d45d2f 100644
--- a/packages/metro-symbolicate/src/SourceMetadataMapConsumer.js
+++ b/packages/metro-symbolicate/src/SourceMetadataMapConsumer.js
@@ -35,8 +35,8 @@ type FunctionMapping = {
   ...
 };
 type SourceNameNormalizer = (
-  v0: string,
-  v1: {readonly sourceRoot?: ?string, ...},
+  sourceInput: string,
+  map: {readonly sourceRoot?: ?string, ...},
 ) => string;
 type MetadataMap = {[source: string]: ?FBSourceMetadata, ...};
 
diff --git a/packages/metro-transform-plugins/src/index.js b/packages/metro-transform-plugins/src/index.js
index c439c872a9..1cf817d61f 100644
--- a/packages/metro-transform-plugins/src/index.js
+++ b/packages/metro-transform-plugins/src/index.js
@@ -24,7 +24,7 @@ export type {Options as InlinePluginOptions} from './inline-plugin';
 export type {PluginOptions as InlineRequiresPluginOptions} from './inline-requires-plugin';
 
 type TransformPlugins = {
-  addParamsToDefineCall(v: string, ...rest: Array<unknown>): string,
+  addParamsToDefineCall(code: string, ...paramsToAdd: Array<unknown>): string,
   constantFoldingPlugin: ConstantFoldingPlugin,
   importExportPlugin: ImportExportPlugin,
   inlinePlugin: InlinePlugin,
diff --git a/packages/metro/src/Bundler/util.js b/packages/metro/src/Bundler/util.js
index 56e5a49e78..ee88d9baef 100644
--- a/packages/metro/src/Bundler/util.js
+++ b/packages/metro/src/Bundler/util.js
@@ -124,7 +124,7 @@ export function createRamBundleGroups<T extends ModuleTransportLike>(
 
 function* filter<A extends number, B extends number>(
   iterator: ArrayMap<A, B>,
-  predicate: (v: [A, Array<B>]) => boolean,
+  predicate: (entry: [A, Array<B>]) => boolean,
 ): Generator<[A, Array<B>], void, void> {
   for (const value of iterator) {
     if (predicate(value)) {
diff --git a/packages/metro/src/DeltaBundler/Serializers/getRamBundleInfo.js b/packages/metro/src/DeltaBundler/Serializers/getRamBundleInfo.js
index f81ac4f5b8..8a39ebc2e8 100644
--- a/packages/metro/src/DeltaBundler/Serializers/getRamBundleInfo.js
+++ b/packages/metro/src/DeltaBundler/Serializers/getRamBundleInfo.js
@@ -30,7 +30,7 @@ type Options = Readonly<{
 }>;
 
 export type RamBundleInfo = {
-  getDependencies: (v: string) => Set<string>,
+  getDependencies: (filePath: string) => Set<string>,
   startupModules: ReadonlyArray<ModuleTransportLike>,
   lazyModules: ReadonlyArray<ModuleTransportLike>,
   groups: Map<number, Set<number>>,
@@ -139,7 +139,7 @@ async function _getRamOptions(
     platform: ?string,
     ...
   },
-  getDependencies: (v: string) => Iterable<string>,
+  getDependencies: (filePath: string) => Iterable<string>,
   getTransformOptions: ?GetTransformOptions,
 ): Promise<
   Readonly<{
diff --git a/packages/metro/src/DeltaBundler/Serializers/helpers/getSourceMapInfo.js b/packages/metro/src/DeltaBundler/Serializers/helpers/getSourceMapInfo.js
index 352ad7a595..cb05bb0a07 100644
--- a/packages/metro/src/DeltaBundler/Serializers/helpers/getSourceMapInfo.js
+++ b/packages/metro/src/DeltaBundler/Serializers/helpers/getSourceMapInfo.js
@@ -22,7 +22,7 @@ export default function getSourceMapInfo(
   module: Module<>,
   options: {
     readonly excludeSource: boolean,
-    readonly shouldAddToIgnoreList: (v: Module<>) => boolean,
+    readonly shouldAddToIgnoreList: (module: Module<>) => boolean,
     getSourceUrl: ?(module: Module<>) => string,
   },
 ): {
diff --git a/packages/metro/src/DeltaBundler/Serializers/helpers/js.js b/packages/metro/src/DeltaBundler/Serializers/helpers/js.js
index dab09f90c8..fe4f7ebcdc 100644
--- a/packages/metro/src/DeltaBundler/Serializers/helpers/js.js
+++ b/packages/metro/src/DeltaBundler/Serializers/helpers/js.js
@@ -31,7 +31,7 @@ import {addParamsToDefineCall} from 'metro-transform-plugins';
 import path from 'node:path';
 
 export type Options = Readonly<{
-  createModuleId: (v: string) => number | string,
+  createModuleId: (absolutePath: string) => number | string,
   dev: boolean,
   includeAsyncPaths: boolean,
   projectRoot: string,
diff --git a/packages/metro/src/DeltaBundler/Serializers/helpers/processModules.js b/packages/metro/src/DeltaBundler/Serializers/helpers/processModules.js
index 174d9556e2..ba44c1eb49 100644
--- a/packages/metro/src/DeltaBundler/Serializers/helpers/processModules.js
+++ b/packages/metro/src/DeltaBundler/Serializers/helpers/processModules.js
@@ -29,7 +29,7 @@ export default function processModules(
     unstable_getAsyncDependencyPath,
   }: Readonly<{
     filter?: (module: Module<>) => boolean,
-    createModuleId: (v: string) => number,
+    createModuleId: (absolutePath: string) => number,
     dev: boolean,
     includeAsyncPaths: boolean,
     projectRoot: string,
diff --git a/packages/metro/src/DeltaBundler/Serializers/hmrJSBundle.js b/packages/metro/src/DeltaBundler/Serializers/hmrJSBundle.js
index 62fb82ab3a..60f22a9390 100644
--- a/packages/metro/src/DeltaBundler/Serializers/hmrJSBundle.js
+++ b/packages/metro/src/DeltaBundler/Serializers/hmrJSBundle.js
@@ -27,7 +27,7 @@ const debug = debugModule('Metro:HMR');
 
 type Options = Readonly<{
   clientUrl: URL,
-  createModuleId: (v: string) => number,
+  createModuleId: (absolutePath: string) => number,
   includeAsyncPaths: boolean,
   projectRoot: string,
   serverRoot: string,
diff --git a/packages/metro/src/DeltaBundler/Serializers/sourceMapGenerator.js b/packages/metro/src/DeltaBundler/Serializers/sourceMapGenerator.js
index 9ff9908936..3e582af7a3 100644
--- a/packages/metro/src/DeltaBundler/Serializers/sourceMapGenerator.js
+++ b/packages/metro/src/DeltaBundler/Serializers/sourceMapGenerator.js
@@ -24,7 +24,9 @@ export type SourceMapGeneratorOptions = Readonly<{
 
 function getSourceMapInfosImpl(
   isBlocking: boolean,
-  onDone: (v: ReadonlyArray<ReturnType<typeof getSourceMapInfo>>) => void,
+  onDone: (
+    sourceMapInfos: ReadonlyArray<ReturnType<typeof getSourceMapInfo>>,
+  ) => void,
   modules: ReadonlyArray<Module<>>,
   options: SourceMapGeneratorOptions,
 ): void {
diff --git a/packages/metro/src/DeltaBundler/Transformer.js b/packages/metro/src/DeltaBundler/Transformer.js
index bba83acf90..c268d2ed78 100644
--- a/packages/metro/src/DeltaBundler/Transformer.js
+++ b/packages/metro/src/DeltaBundler/Transformer.js
@@ -28,7 +28,7 @@ import path from 'node:path';
 const debug = debugModule('Metro:Transformer');
 
 type GetOrComputeSha1Fn = (
-  v: string,
+  filePath: string,
 ) => Promise<Readonly<{content?: Buffer, sha1: string}>>;
 
 export default class Transformer {
diff --git a/packages/metro/src/DeltaBundler/Worker.flow.js b/packages/metro/src/DeltaBundler/Worker.flow.js
index f373da8321..c26dbf155a 100644
--- a/packages/metro/src/DeltaBundler/Worker.flow.js
+++ b/packages/metro/src/DeltaBundler/Worker.flow.js
@@ -25,12 +25,12 @@ export type {JsTransformOptions as TransformOptions} from 'metro-transform-worke
 
 type TransformerInterface = {
   transform(
-    v0: JsTransformerConfig,
-    v1: string,
-    v2: string,
-    v3: Buffer,
-    v4: JsTransformOptions,
-    v5: ?string,
+    config: JsTransformerConfig,
+    projectRoot: string,
+    projectRelativePath: string,
+    data: Buffer,
+    options: JsTransformOptions,
+    assetUrlPath: ?string,
   ): Promise<TransformResult<>>,
 };
 
diff --git a/packages/metro/src/DeltaBundler/__tests__/Graph-test.js b/packages/metro/src/DeltaBundler/__tests__/Graph-test.js
index 869a687e68..8d72419ae6 100644
--- a/packages/metro/src/DeltaBundler/__tests__/Graph-test.js
+++ b/packages/metro/src/DeltaBundler/__tests__/Graph-test.js
@@ -469,7 +469,7 @@ Generate the initial dependency graph:
 Paths are given as posix and mapped through `p`, so that tests exercising
 path-sensitive logic can use system paths.
 */
-function setUpInitialGraph(p: (v: string) => string) {
+function setUpInitialGraph(p: (posixPath: string) => string) {
   mockedDependencies = new Set();
   mockedDependencyTree = new Map();
 
diff --git a/packages/metro/src/DeltaBundler/__tests__/test-utils.js b/packages/metro/src/DeltaBundler/__tests__/test-utils.js
index 1419c96be0..8c2e22a331 100644
--- a/packages/metro/src/DeltaBundler/__tests__/test-utils.js
+++ b/packages/metro/src/DeltaBundler/__tests__/test-utils.js
@@ -63,7 +63,7 @@ export const createPathNormalizer = (
   platform: 'win32' | 'posix' = process.platform === 'win32'
     ? 'win32'
     : 'posix',
-): ((v: string) => string) =>
+): ((posixPath: string) => string) =>
   platform === 'win32'
     ? posixPath => posixPath.replace(/^\//, 'C:\\').replaceAll('/', '\\')
     : posixPath => posixPath;
diff --git a/packages/metro/src/DeltaBundler/buildSubgraph.js b/packages/metro/src/DeltaBundler/buildSubgraph.js
index b3a4a98730..b274923c88 100644
--- a/packages/metro/src/DeltaBundler/buildSubgraph.js
+++ b/packages/metro/src/DeltaBundler/buildSubgraph.js
@@ -27,7 +27,10 @@ import path from 'node:path';
 type Parameters<T> = Readonly<{
   resolve: ResolveFn,
   transform: TransformFn<T>,
-  shouldTraverse: (v0: ResolvedDependency, v1: ?VirtualSource) => boolean,
+  shouldTraverse: (
+    dependency: ResolvedDependency,
+    virtualSource: ?VirtualSource,
+  ) => boolean,
 }>;
 
 // The source hash seen for each virtual module, to catch edges that disagree.
diff --git a/packages/metro/src/DeltaBundler/types.js b/packages/metro/src/DeltaBundler/types.js
index dbdd53eeb2..9aa22b4f0d 100644
--- a/packages/metro/src/DeltaBundler/types.js
+++ b/packages/metro/src/DeltaBundler/types.js
@@ -158,8 +158,8 @@ export type TransformResultWithSource<T = MixedOutput> = Readonly<{
 }>;
 
 export type TransformFn<T = MixedOutput> = (
-  v0: string,
-  v1: ?VirtualSource,
+  modulePath: string,
+  virtualSource: ?VirtualSource,
 ) => Promise<TransformResultWithSource<T>>;
 
 export type ResolveFn = (
diff --git a/packages/metro/src/HmrServer.js b/packages/metro/src/HmrServer.js
index 4a5408625d..f80f290bb1 100644
--- a/packages/metro/src/HmrServer.js
+++ b/packages/metro/src/HmrServer.js
@@ -42,7 +42,7 @@ const {createActionStartEntry, createActionEndEntry, log} = Logger;
 export type Client = {
   optedIntoHMR: boolean,
   revisionIds: Array<RevisionId>,
-  readonly sendFn: (v: string) => void,
+  readonly sendFn: (message: string) => void,
 };
 
 type ClientGroup = {
@@ -53,9 +53,12 @@ type ClientGroup = {
   readonly graphOptions: GraphOptions,
 };
 
-function send(sendFns: Array<(v: string) => void>, message: HmrMessage): void {
+function send(
+  sendFns: Array<(message: string) => void>,
+  message: HmrMessage,
+): void {
   const strMessage = JSON.stringify(message);
-  sendFns.forEach((sendFn: (v: string) => void) => sendFn(strMessage));
+  sendFns.forEach((sendFn: (message: string) => void) => sendFn(strMessage));
 }
 
 /**
diff --git a/packages/metro/src/IncrementalBundler.js b/packages/metro/src/IncrementalBundler.js
index a8745f2702..e3d0fc8051 100644
--- a/packages/metro/src/IncrementalBundler.js
+++ b/packages/metro/src/IncrementalBundler.js
@@ -350,7 +350,7 @@ export default class IncrementalBundler {
       absoluteEntryFiles.map(
         (entryFile: string) =>
           new Promise(
-            (resolve: (v: void) => void, reject: (v: unknown) => unknown) => {
+            (resolve: () => void, reject: (reason: unknown) => unknown) => {
               // This should throw an error if the file doesn't exist.
               // Using this instead of fs.exists to account for SimLinks.
               fs.realpath(entryFile, err => {
diff --git a/packages/metro/src/ModuleGraph/worker/collectDependencies.js b/packages/metro/src/ModuleGraph/worker/collectDependencies.js
index 33ecef3385..c5a561da83 100644
--- a/packages/metro/src/ModuleGraph/worker/collectDependencies.js
+++ b/packages/metro/src/ModuleGraph/worker/collectDependencies.js
@@ -96,7 +96,7 @@ export type State = {
   allowOptionalDependencies: AllowOptionalDependencies,
   /** Enable `require.context` statements which can be used to import multiple files in a directory. */
   unstable_allowRequireContext: boolean,
-  unstable_isESMImportAtSource: ?(v: ReadonlySourceLocation) => boolean,
+  unstable_isESMImportAtSource: ?(location: ReadonlySourceLocation) => boolean,
 };
 
 export type Options = Readonly<{
@@ -109,7 +109,7 @@ export type Options = Readonly<{
   dependencyTransformer?: DependencyTransformer,
   /** Enable `require.context` statements which can be used to import multiple files in a directory. */
   unstable_allowRequireContext: boolean,
-  unstable_isESMImportAtSource?: ?(v: ReadonlySourceLocation) => boolean,
+  unstable_isESMImportAtSource?: ?(location: ReadonlySourceLocation) => boolean,
 }>;
 
 export type CollectedDependencies = Readonly<{
diff --git a/packages/metro/src/Server.js b/packages/metro/src/Server.js
index 98db21b3ad..1582eb04ec 100644
--- a/packages/metro/src/Server.js
+++ b/packages/metro/src/Server.js
@@ -604,7 +604,7 @@ export default class Server {
   ) => void = (
     req: IncomingMessage,
     res: ServerResponse,
-    next: (v: ?Error) => void,
+    next: (error: ?Error) => void,
   ) => {
     this._processRequest(req, res, next).catch(next);
   };
@@ -627,7 +627,7 @@ export default class Server {
   async _processRequest(
     req: IncomingMessage,
     res: ServerResponse,
-    next: (v: ?Error) => void,
+    next: (error: ?Error) => void,
   ): Promise<void> {
     const originalUrl = req.url;
     debug('Handling request:    %s', originalUrl);
diff --git a/packages/metro/src/Server/symbolicate.js b/packages/metro/src/Server/symbolicate.js
index e59ada4a0d..31add751f4 100644
--- a/packages/metro/src/Server/symbolicate.js
+++ b/packages/metro/src/Server/symbolicate.js
@@ -108,7 +108,7 @@ function originalPositionInTuples(
 
 function createFunctionNameGetter(
   module: ExplodedSourceMapModule,
-): (v: Position) => ?string {
+): (position: Position) => ?string {
   const consumer = new SourceMetadataMapConsumer(
     {
       version: 3,
@@ -144,7 +144,7 @@ export default async function symbolicate(
       readonly map: Array<MetroSourceMapSegmentTuple> | VlqMap,
       readonly path: string,
     },
-    (v: Position) => ?string,
+    (position: Position) => ?string,
   >();
 
   function findModule(frame: StackFrameInput): ?ExplodedSourceMapModule {
diff --git a/packages/metro/src/__tests__/HmrServer-test.js b/packages/metro/src/__tests__/HmrServer-test.js
index c4c8b7782a..d4bd0c577f 100644
--- a/packages/metro/src/__tests__/HmrServer-test.js
+++ b/packages/metro/src/__tests__/HmrServer-test.js
@@ -169,7 +169,7 @@ describe('HmrServer', () => {
 
     connect = async (
       relativeUrl: string,
-      sendFn?: (v: string) => void,
+      sendFn?: (message: string) => void,
       {baseUrl = 'ws://localhost'}: {baseUrl?: string} = {},
     ) => {
       const absoluteUrl = baseUrl + relativeUrl;
@@ -191,7 +191,7 @@ describe('HmrServer', () => {
     message = async (
       client: Client,
       message: HmrClientMessage,
-      sendFn?: (v: string) => void,
+      sendFn?: (message: string) => void,
     ) => {
       await hmrServer.onClientMessage(
         client,
diff --git a/packages/metro/src/lib/debounceAsyncQueue.js b/packages/metro/src/lib/debounceAsyncQueue.js
index 73df7e2001..aceb857a84 100644
--- a/packages/metro/src/lib/debounceAsyncQueue.js
+++ b/packages/metro/src/lib/debounceAsyncQueue.js
@@ -18,14 +18,14 @@ export default function debounceAsyncQueue<T>(
   let timeout;
   let waiting = false;
   let executing = false;
-  let callbacks: Array<(v: T) => void> = [];
+  let callbacks: Array<(result: T) => void> = [];
 
   async function execute(): Promise<void> {
     const currentCallbacks = callbacks;
     callbacks = [];
     executing = true;
     const res = await fn();
-    currentCallbacks.forEach((c: (v: T) => void) => c(res));
+    currentCallbacks.forEach((c: (result: T) => void) => c(res));
     executing = false;
     if (callbacks.length > 0) {
       await execute();
@@ -33,19 +33,21 @@ export default function debounceAsyncQueue<T>(
   }
 
   return () =>
-    new Promise((resolve: (v: T) => void, reject: (v: unknown) => void) => {
-      callbacks.push(resolve);
+    new Promise(
+      (resolve: (result: T) => void, reject: (reason: unknown) => void) => {
+        callbacks.push(resolve);
 
-      if (!executing) {
-        if (waiting) {
-          clearTimeout(timeout);
-        } else {
-          waiting = true;
+        if (!executing) {
+          if (waiting) {
+            clearTimeout(timeout);
+          } else {
+            waiting = true;
+          }
+          timeout = setTimeout(async () => {
+            waiting = false;
+            await execute();
+          }, delay);
         }
-        timeout = setTimeout(async () => {
-          waiting = false;
-          await execute();
-        }, delay);
-      }
-    });
+      },
+    );
 }
diff --git a/packages/metro/src/lib/getAppendScripts.js b/packages/metro/src/lib/getAppendScripts.js
index a20121c369..8eb0943fe7 100644
--- a/packages/metro/src/lib/getAppendScripts.js
+++ b/packages/metro/src/lib/getAppendScripts.js
@@ -20,17 +20,17 @@ import nullthrows from 'nullthrows';
 
 type Options<T extends number | string> = Readonly<{
   asyncRequireModulePath: string,
-  createModuleId: (v: string) => T,
+  createModuleId: (absolutePath: string) => T,
   getRunModuleStatement: (moduleId: T, globalPrefix: string) => string,
   globalPrefix: string,
   inlineSourceMap: ?boolean,
   processModuleFilter: (module: Module<>) => boolean,
   runBeforeMainModule: ReadonlyArray<string>,
   runModule: boolean,
-  shouldAddToIgnoreList: (v: Module<>) => boolean,
+  shouldAddToIgnoreList: (module: Module<>) => boolean,
   sourceMapUrl: ?string,
   sourceUrl: ?string,
-  getSourceUrl: ?(v: Module<>) => string,
+  getSourceUrl: ?(module: Module<>) => string,
   ...
 }>;
 
diff --git a/packages/metro/src/lib/pathUtils.js b/packages/metro/src/lib/pathUtils.js
index 1e2e3ef6de..ae7b7bf84d 100644
--- a/packages/metro/src/lib/pathUtils.js
+++ b/packages/metro/src/lib/pathUtils.js
@@ -10,7 +10,7 @@
 
 import * as path from 'node:path';
 
-export const normalizePathSeparatorsToPosix: (v: string) => string =
+export const normalizePathSeparatorsToPosix: (filePath: string) => string =
   path.sep === '/'
     ? filePath => filePath
     : filePath => filePath.replaceAll('\\', '/');
diff --git a/packages/metro/src/shared/output/RamBundle/as-indexed-file.js b/packages/metro/src/shared/output/RamBundle/as-indexed-file.js
index ba4ff703b6..9eb9d95568 100644
--- a/packages/metro/src/shared/output/RamBundle/as-indexed-file.js
+++ b/packages/metro/src/shared/output/RamBundle/as-indexed-file.js
@@ -96,11 +96,13 @@ function writeBuffers(
   buffers: Array<Buffer>,
 ): Promise<void> {
   buffers.forEach((buffer: Buffer) => stream.write(buffer));
-  return new Promise((resolve: () => void, reject: (v: unknown) => unknown) => {
-    stream.on('error', reject);
-    stream.on('finish', () => resolve());
-    stream.end();
-  });
+  return new Promise(
+    (resolve: () => void, reject: (reason: unknown) => unknown) => {
+      stream.on('error', reject);
+      stream.on('finish', () => resolve());
+      stream.end();
+    },
+  );
 }
 
 function nullTerminatedBuffer(
diff --git a/packages/metro/src/shared/output/bundle.flow.js b/packages/metro/src/shared/output/bundle.flow.js
index c36abd997d..b96cc6ff07 100644
--- a/packages/metro/src/shared/output/bundle.flow.js
+++ b/packages/metro/src/shared/output/bundle.flow.js
@@ -68,7 +68,7 @@ export async function save(
     ...
   },
   options: OutputOptions,
-  log: (v: string) => void,
+  log: (message: string) => void,
 ): Promise<unknown> {
   const {
     bundleOutput,
@@ -101,7 +101,7 @@ export async function save(
   }
 
   // Wait until everything is written to disk.
-  await Promise.all(writeFns.map((cb: (v: void) => unknown) => cb()));
+  await Promise.all(writeFns.map((cb: () => unknown) => cb()));
 }
 
 export const formatName = 'bundle';
diff --git a/private/metro-memory-fs/src/index.js b/private/metro-memory-fs/src/index.js
index 9396f720d3..f26e8ec246 100644
--- a/private/metro-memory-fs/src/index.js
+++ b/private/metro-memory-fs/src/index.js
@@ -222,7 +222,7 @@ class MemoryFs {
     offset: number,
     length: number,
     position: ?number,
-    callback: (v0: ?Error, v1: ?number) => unknown,
+    callback: (error: ?Error, bytesRead: ?number) => unknown,
   ) => void;
   readFile: (
     filePath: FilePath,
@@ -233,20 +233,22 @@ class MemoryFs {
           ...
         }
       | Encoding
-      | ((v0: ?Error, v1: ?Buffer | string) => unknown),
-    callback?: (v0: ?Error, v1: ?Buffer | string) => unknown,
+      | ((error: ?Error, data: ?Buffer | string) => unknown),
+    callback?: (error: ?Error, data: ?Buffer | string) => unknown,
   ) => void;
   realpath: (
     filePath: FilePath,
-    callback: (v0: ?Error, v1: ?string) => unknown,
+    callback: (error: ?Error, resolvedPath: ?string) => unknown,
   ) => void;
   write: (
     fd: number,
     bufferOrString: Buffer | string,
-    offsetOrPosition?: number | ((v0: ?Error, v1: number) => unknown),
-    lengthOrEncoding?: number | string | ((v0: ?Error, v1: number) => unknown),
-    position?: number | ((v0: ?Error, v1: number) => unknown),
-    callback?: (v0: ?Error, v1: number) => unknown,
+    offsetOrPosition?:
+      number | ((error: ?Error, bytesWritten: number) => unknown),
+    lengthOrEncoding?:
+      number | string | ((error: ?Error, bytesWritten: number) => unknown),
+    position?: number | ((error: ?Error, bytesWritten: number) => unknown),
+    callback?: (error: ?Error, bytesWritten: number) => unknown,
   ) => void;
   writeFile: (
     filePath: FilePath,
@@ -259,8 +261,8 @@ class MemoryFs {
           ...
         }
       | Encoding
-      | ((v: ?Error) => unknown),
-    callback?: (v: ?Error) => unknown,
+      | ((error: ?Error) => unknown),
+    callback?: (error: ?Error) => unknown,
   ) => void;
 
   constructor(options?: ?Options) {
diff --git a/scripts/generateTypeScriptDefinitions.js b/scripts/generateTypeScriptDefinitions.js
index 1f63649416..0a8d24d67b 100644
--- a/scripts/generateTypeScriptDefinitions.js
+++ b/scripts/generateTypeScriptDefinitions.js
@@ -419,7 +419,7 @@ function removeDeclareConstAtLine(
 function findBlockStart(
   lines: ReadonlyArray<string>,
   lineIndex: number,
-  predicate: (v: string) => boolean,
+  predicate: (line: string) => boolean,
 ): ?number {
   for (let i = lineIndex; i >= 0; i--) {
     if (predicate(lines[i])) {