Update docs/types for process (#3631)

* Update docs/types for process

* Tweaks

* Tweaks

* Fix types

6 files changed, 210 insertions, 59 deletions

diff --git a/docs/runtime/nodejs-apis.md b/docs/runtime/nodejs-apis.md
index 3dfe76b97..2e45fd945 100644
--- a/docs/runtime/nodejs-apis.md
+++ b/docs/runtime/nodejs-apis.md
@@ -510,7 +510,7 @@ The table below lists all globals implemented by Node.js and Bun's current compa
 
 - {% anchor id="node_process" %} [`process`](https://nodejs.org/api/process.html) {% /anchor %}
 - 🟡
-- Missing `process.allowedNodeEnvironmentFlags` `process.channel()` `process.connected` `process.constrainedMemory()` `process.cpuUsage()` `process.debugPort` `process.disconnect()` `process.{get|set}ActiveResourcesInfo()` `process.{get|set}{uid|gid|egid|euid|groups}()` `process.hasUncaughtExceptionCaptureCallback` `process.initGroups()` `process.kill()` `process.listenerCount` `process.memoryUsage()` `process.report` `process.resourceUsage()` `process.setSourceMapsEnabled()` `process.send()`.
+- Missing `process.allowedNodeEnvironmentFlags` `process.channel()` `process.connected` `process.constrainedMemory()` `process.disconnect()` `process.getActiveResourcesInfo/setActiveResourcesInfo()` `process.setuid/setgid/setegid/seteuid/setgroups()` `process.hasUncaughtExceptionCaptureCallback` `process.initGroups()` `process.report` `process.resourceUsage()` `process.send()`.
 
 ---
 
diff --git a/packages/bun-types/ffi.d.ts b/packages/bun-types/ffi.d.ts
index 9705e810b..c4811e98a 100644
--- a/packages/bun-types/ffi.d.ts
+++ b/packages/bun-types/ffi.d.ts
@@ -380,6 +380,7 @@ declare module "bun:ffi" {
     [FFIType.cstring]: CString;
     [FFIType.i64_fast]: number | bigint;
     [FFIType.u64_fast]: number | bigint;
+    [FFIType.function]: (...args: any[]) => any;
   }
   interface FFITypeStringToType {
     ["char"]: FFIType.char;
diff --git a/packages/bun-types/fs.d.ts b/packages/bun-types/fs.d.ts
index 379e0ef25..cc3483b53 100644
--- a/packages/bun-types/fs.d.ts
+++ b/packages/bun-types/fs.d.ts
@@ -3999,7 +3999,7 @@ declare module "fs" {
     recursive?: boolean;
     signal?: AbortSignal;
   };
-  type WatchEventType = "rename" | "change" | "error" | "close";
+  export type WatchEventType = "rename" | "change" | "error" | "close";
   type WatchListener<T> = (
     event: WatchEventType,
     filename: T | Error | undefined,
diff --git a/packages/bun-types/fs/promises.d.ts b/packages/bun-types/fs/promises.d.ts
index 2b908fceb..953c59a42 100644
--- a/packages/bun-types/fs/promises.d.ts
+++ b/packages/bun-types/fs/promises.d.ts
@@ -27,6 +27,7 @@ declare module "fs/promises" {
     RmOptions,
     RmDirOptions,
     WatchOptions,
+    WatchEventType,
   } from "node:fs";
 
   const constants: typeof import("node:fs")["constants"];
@@ -711,62 +712,74 @@ declare module "fs/promises" {
    */
   function rmdir(path: PathLike, options?: RmDirOptions): Promise<void>;
 
+  interface FileChangeInfo<T extends string | Buffer> {
+    eventType: WatchEventType;
+    filename: T;
+  }
   /**
-     * Returns an async iterator that watches for changes on `filename`, where `filename`is either a file or a directory.
-     *
-     * ```js
-     * const { watch } = require('node:fs/promises');
-     *
-     * const ac = new AbortController();
-     * const { signal } = ac;
-     * setTimeout(() => ac.abort(), 10000);
-     *
-     * (async () => {
-     *   try {
-     *     const watcher = watch(__filename, { signal });
-     *     for await (const event of watcher)
-     *       console.log(event);
-     *   } catch (err) {
-     *     if (err.name === 'AbortError')
-     *       return;
-     *     throw err;
-     *   }
-     * })();
-     * ```
-     *
-     * On most platforms, `'rename'` is emitted whenever a filename appears or
-     * disappears in the directory.
-     *
-     * All the `caveats` for `fs.watch()` also apply to `fsPromises.watch()`.
-     * @since v0.6.8
-     * @return of objects with the properties:
-     */
-      function watch(
-        filename: PathLike,
-        options:
-            | (WatchOptions & {
-                  encoding: 'buffer';
-              })
-            | 'buffer'
-    ): AsyncIterable<FileChangeInfo<Buffer>>;
-    /**
-     * Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.
-     * @param filename A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
-     * @param options Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options.
-     * If `encoding` is not supplied, the default of `'utf8'` is used.
-     * If `persistent` is not supplied, the default of `true` is used.
-     * If `recursive` is not supplied, the default of `false` is used.
-     */
-    function watch(filename: PathLike, options?: WatchOptions | BufferEncoding): AsyncIterable<FileChangeInfo<string>>;
-    /**
-     * Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.
-     * @param filename A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
-     * @param options Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options.
-     * If `encoding` is not supplied, the default of `'utf8'` is used.
-     * If `persistent` is not supplied, the default of `true` is used.
-     * If `recursive` is not supplied, the default of `false` is used.
-     */
-    function watch(filename: PathLike, options: WatchOptions | string): AsyncIterable<FileChangeInfo<string>> | AsyncIterable<FileChangeInfo<Buffer>>;
+   * Returns an async iterator that watches for changes on `filename`, where `filename`is either a file or a directory.
+   *
+   * ```js
+   * const { watch } = require('node:fs/promises');
+   *
+   * const ac = new AbortController();
+   * const { signal } = ac;
+   * setTimeout(() => ac.abort(), 10000);
+   *
+   * (async () => {
+   *   try {
+   *     const watcher = watch(__filename, { signal });
+   *     for await (const event of watcher)
+   *       console.log(event);
+   *   } catch (err) {
+   *     if (err.name === 'AbortError')
+   *       return;
+   *     throw err;
+   *   }
+   * })();
+   * ```
+   *
+   * On most platforms, `'rename'` is emitted whenever a filename appears or
+   * disappears in the directory.
+   *
+   * All the `caveats` for `fs.watch()` also apply to `fsPromises.watch()`.
+   * @since v0.6.8
+   * @return of objects with the properties:
+   */
+  function watch(
+    filename: PathLike,
+    options:
+      | (WatchOptions & {
+          encoding: "buffer";
+        })
+      | "buffer",
+  ): AsyncIterable<FileChangeInfo<Buffer>>;
+  /**
+   * Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.
+   * @param filename A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
+   * @param options Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options.
+   * If `encoding` is not supplied, the default of `'utf8'` is used.
+   * If `persistent` is not supplied, the default of `true` is used.
+   * If `recursive` is not supplied, the default of `false` is used.
+   */
+  function watch(
+    filename: PathLike,
+    options?: WatchOptions | BufferEncoding,
+  ): AsyncIterable<FileChangeInfo<string>>;
+  /**
+   * Watch for changes on `filename`, where `filename` is either a file or a directory, returning an `FSWatcher`.
+   * @param filename A path to a file or directory. If a URL is provided, it must use the `file:` protocol.
+   * @param options Either the encoding for the filename provided to the listener, or an object optionally specifying encoding, persistent, and recursive options.
+   * If `encoding` is not supplied, the default of `'utf8'` is used.
+   * If `persistent` is not supplied, the default of `true` is used.
+   * If `recursive` is not supplied, the default of `false` is used.
+   */
+  function watch(
+    filename: PathLike,
+    options: WatchOptions | string,
+  ):
+    | AsyncIterable<FileChangeInfo<string>>
+    | AsyncIterable<FileChangeInfo<Buffer>>;
 }
 
 declare module "node:fs/promises" {
diff --git a/packages/bun-types/globals.d.ts b/packages/bun-types/globals.d.ts
index d74fabf1f..cb9f3d1bc 100644
--- a/packages/bun-types/globals.d.ts
+++ b/packages/bun-types/globals.d.ts
@@ -75,6 +75,34 @@ interface ArrayConstructor {
   ): Promise<Array<T>>;
 }
 
+type UncaughtExceptionOrigin = "uncaughtException" | "unhandledRejection";
+type MultipleResolveType = "resolve" | "reject";
+type BeforeExitListener = (code: number) => void;
+type DisconnectListener = () => void;
+type ExitListener = (code: number) => void;
+type RejectionHandledListener = (promise: Promise<unknown>) => void;
+type UncaughtExceptionListener = (
+  error: Error,
+  origin: UncaughtExceptionOrigin,
+) => void;
+/**
+ * Most of the time the unhandledRejection will be an Error, but this should not be relied upon
+ * as *anything* can be thrown/rejected, it is therefore unsafe to assume that the value is an Error.
+ */
+type UnhandledRejectionListener = (
+  reason: unknown,
+  promise: Promise<unknown>,
+) => void;
+type WarningListener = (warning: Error) => void;
+type MessageListener = (message: unknown, sendHandle: unknown) => void;
+type SignalsListener = (signal: Signals) => void;
+type MultipleResolveListener = (
+  type: MultipleResolveType,
+  promise: Promise<unknown>,
+  value: unknown,
+) => void;
+// type WorkerListener = (worker: Worker) => void;
+
 interface Console {
   /**
    * Asynchronously read lines from standard input (fd 0)
@@ -369,6 +397,8 @@ interface Process {
   argv: string[];
   execArgv: string[];
   env: import("bun").Env;
+  allowedNodeEnvironmentFlags: Set<string>;
+  debugPort: number;
 
   /** Whether you are using Bun */
   isBun: 1; // FIXME: this should actually return a boolean
@@ -377,16 +407,29 @@ interface Process {
   chdir(directory: string): void;
   cwd(): string;
   exit(code?: number): never;
+  reallyExit(code?: number): never;
   getgid(): number;
-  setgid(id: number | string): void;
+  // setgid(id: number | string): void;
   getuid(): number;
-  setuid(id: number | string): void;
+  // setuid(id: number | string): void;
+  geteuid: () => number;
+  // seteuid: (id: number | string) => void;
+  getegid: () => number;
+  // setegid: (id: number | string) => void;
+  getgroups: () => number[];
+  // setgroups?: (groups: ReadonlyArray<string | number>) => void;
   dlopen(module: { exports: any }, filename: string, flags?: number): void;
   stdin: import("stream").Duplex & { isTTY: boolean };
   stdout: import("stream").Writable & { isTTY: boolean };
   stderr: import("stream").Writable & { isTTY: boolean };
 
   /**
+   *
+   * @deprecated This is deprecated; use the "node:assert" module instead.
+   */
+  assert(value: unknown, message?: string | Error): asserts value;
+
+  /**
    * exit the process with a fatal exception, sending SIGABRT
    */
   abort(): never;
@@ -435,6 +478,49 @@ interface Process {
   setSourceMapsEnabled(enabled: boolean): void;
 
   kill(pid: number, signal?: string | number): void;
+
+  on(event: "beforeExit", listener: BeforeExitListener): this;
+  // on(event: "disconnect", listener: DisconnectListener): this;
+  on(event: "exit", listener: ExitListener): this;
+  // on(event: "rejectionHandled", listener: RejectionHandledListener): this;
+  // on(event: "uncaughtException", listener: UncaughtExceptionListener): this;
+  // on(
+  //   event: "uncaughtExceptionMonitor",
+  //   listener: UncaughtExceptionListener,
+  // ): this;
+  // on(event: "unhandledRejection", listener: UnhandledRejectionListener): this;
+  // on(event: "warning", listener: WarningListener): this;
+  // on(event: "message", listener: MessageListener): this;
+  on(event: Signals, listener: SignalsListener): this;
+  // on(event: "multipleResolves", listener: MultipleResolveListener): this;
+  // on(event: "worker", listener: WorkerListener): this;
+  on(event: string | symbol, listener: (...args: any[]) => void): this;
+  once(event: "beforeExit", listener: BeforeExitListener): this;
+  // once(event: "disconnect", listener: DisconnectListener): this;
+  once(event: "exit", listener: ExitListener): this;
+  // once(event: "rejectionHandled", listener: RejectionHandledListener): this;
+  // once(event: "uncaughtException", listener: UncaughtExceptionListener): this;
+  // once(
+  //   event: "uncaughtExceptionMonitor",
+  //   listener: UncaughtExceptionListener,
+  // ): this;
+  // once(event: "unhandledRejection", listener: UnhandledRejectionListener): this;
+  // once(event: "warning", listener: WarningListener): this;
+  // once(event: "message", listener: MessageListener): this;
+  once(event: Signals, listener: SignalsListener): this;
+  // once(event: "multipleResolves", listener: MultipleResolveListener): this;
+  // once(event: "worker", listener: WorkerListener): this;
+  once(event: string | symbol, listener: (...args: any[]) => void): this;
+
+  /**
+   * Returns the number of listeners listening for the event named `eventName`.
+   * If `listener` is provided, it will return how many times the listener is found
+   * in the list of the listeners of the event.
+   * @since v3.2.0
+   * @param eventName The name of the event being listened for
+   * @param listener The event handler function
+   */
+  listenerCount(eventName: string | symbol, listener?: Function): number;
 }
 
 interface MemoryUsageObject {
diff --git a/packages/bun-types/tests/process.test-d.ts b/packages/bun-types/tests/process.test-d.ts
new file mode 100644
index 000000000..0aa0f9b27
--- /dev/null
+++ b/packages/bun-types/tests/process.test-d.ts
@@ -0,0 +1,51 @@
+process.memoryUsage();
+process.cpuUsage().system;
+process.cpuUsage().user;
+process.on("SIGINT", () => {
+  console.log("Interrupt from keyboard");
+});
+
+process.on("beforeExit", code => {
+  console.log("Event loop is empty and no work is left to schedule.", code);
+});
+
+process.on("exit", code => {
+  console.log("Exiting with code:", code);
+});
+process.kill(123, "SIGTERM");
+
+process.getegid();
+process.geteuid();
+process.getgid();
+process.getgroups();
+process.getuid();
+
+process.once("SIGINT", () => {
+  console.log("Interrupt from keyboard");
+});
+
+process.reallyExit();
+
+process.assert(false, "PleAsE don't Use THIs It IS dEpReCATED");
+
+console.log(process.allowedNodeEnvironmentFlags);
+// console.log(process.channel);
+// console.log(process.connected);
+// console.log(process.constrainedMemory);
+console.log(process.debugPort);
+// console.log(process.disconnect);
+// console.log(process.getActiveResourcesInfo);
+// console.log(process.setActiveResourcesInfo);
+// console.log(process.setuid);
+// console.log(process.setgid);
+// console.log(process.setegid);
+// console.log(process.seteuid);
+// console.log(process.setgroups);
+// console.log(process.hasUncaughtExceptionCaptureCallback);
+// console.log(process.initGroups);
+console.log(process.listenerCount("exit"));
+console.log(process.memoryUsage());
+// console.log(process.report);
+// console.log(process.resourceUsage);
+// console.log(process.setSourceMapsEnabled());
+// console.log(process.send);