feat: add node child_process module

Signed-off-by: Sam Gammon <[email protected]>

elide/runtime/js/modules/child_process/child_process.ts

@@ -17,4 +17,181 @@
  * Provides primitives for spawning child processes.
  */
 
-export {};
+const { node_child_process, NodeChildProcess } = primordials;
+
+/**
+ * Class which implements `ChildProcess` handle behavior.
+ */
+export const ChildProcess = NodeChildProcess;
+
+/**
+ * Callback for child process execution via methods like `exec`.
+ */
+export type ExecCallback = (error: Error | null, stdout: string, stderr: string) => void;
+
+/**
+ * Create a child process which calls into the provided `command`, with the provided `options` and optional `callback`.
+ *
+ * @param command Command to execute in the child-process
+ * @param options Options to apply, if desired (or otherwise the argument in this position is the callback)
+ * @param cbk Callback to provide (also option)
+ * @return Child process handle.
+ */
+export function exec(command: string, options?: object | ExecCallback, cbk?: ExecCallback): typeof ChildProcess {
+  return node_child_process.exec(command, options as any, cbk);
+}
+
+/**
+ * Create a child process which calls into the provided `command`, with the provided `options` and optional `callback`.
+ *
+ * @param command Command to execute in the child-process
+ * @param argsOrOptionsOrCallback Args, or options, or the callback (or nothing).
+ * @param optionsOrCallback Options, or the callback (or nothing).
+ * @param cbk Callback to provide (also optional).
+ * @return Child process handle.
+ */
+export function execFile(
+  command: string,
+  argsOrOptionsOrCallback: object | string[] | ExecCallback,
+  optionsOrCallback: object | ExecCallback,
+  cbk?: ExecCallback,
+): typeof ChildProcess {
+  // resolve callback
+  const callback = cbk || (
+    typeof argsOrOptionsOrCallback === 'function' ? argsOrOptionsOrCallback : (
+      typeof optionsOrCallback === 'function' ? optionsOrCallback : undefined
+    )
+  );
+
+  // resolve args
+  const args = (
+    Array.isArray(argsOrOptionsOrCallback) ? argsOrOptionsOrCallback : []
+  );
+
+  // resolve options
+  const options = (
+    typeof optionsOrCallback !== 'function' ? optionsOrCallback : (
+      typeof argsOrOptionsOrCallback !== 'function' ? argsOrOptionsOrCallback : undefined
+    )
+  );
+
+  return node_child_process.execFile(
+    command,
+    args,
+    options,
+    callback,
+  );
+}
+
+/**
+ * Fork with a new child process with the provided `modulePath` entrypoint.
+ *
+ * @param modulePath Module path to fork
+ * @param argsOrOptionsOrCallback Arguments, options, or callback to pass to the forked process
+ * @param argsOrCallback Arguments or callback to pass to the forked process
+ * @param cbk Callback to pass to the forked process
+ * @return Child process handle.
+ */
+export function fork(
+  modulePath: string,
+  argsOrOptionsOrCallback?: object | string[],
+  optionsOrCallback?: object | ExecCallback,
+  cbk?: ExecCallback,
+): typeof ChildProcess {
+  // resolve callback
+  const callback = cbk || (
+    typeof argsOrOptionsOrCallback === 'function' ? argsOrOptionsOrCallback : (
+      typeof optionsOrCallback === 'function' ? optionsOrCallback : undefined
+    )
+  );
+
+  // resolve args
+  const args = (
+    Array.isArray(argsOrOptionsOrCallback) ? argsOrOptionsOrCallback : []
+  );
+
+  // resolve options
+  const options = (
+    typeof optionsOrCallback !== 'function' ? optionsOrCallback : (
+      typeof argsOrOptionsOrCallback !== 'function' ? argsOrOptionsOrCallback : undefined
+    )
+  );
+
+  return node_child_process.fork(
+    modulePath,
+    args,
+    options,
+    callback,
+  );
+}
+
+/**
+ * Spawn a new child process with the provided `command`.
+ *
+ * @param command Command to spawn
+ * @param argsOrOptions Arguments or options to apply to the command, if desired
+ * @param options Options to apply to the command, if desired
+ * @return Child process handle.
+ */
+export function spawn(
+  command: string,
+  argsOrOptions?: object | string[],
+  options?: object,
+): typeof ChildProcess {
+  return node_child_process.spawn(
+    command,
+    !!options ? argsOrOptions : undefined,
+    !!options ? options : argsOrOptions,
+  );
+}
+
+/**
+ * Execute a command synchronously.
+ *
+ * @param command Command string to execute
+ * @param options Options to apply to the command, if desired
+ * @return String or buffer, depending on output encoding settings
+ */
+export function execSync(command: string, options?: object): string | Buffer {
+  return node_child_process.execSync(command, options);
+}
+
+/**
+ * Execute a specific file synchronously.
+ *
+ * @param file File to execute
+ * @param argsOrOptions Arguments or options to apply to the command, if desired
+ * @param options Options to apply to the command, if desired
+ * @return String or buffer, depending on output encoding settings
+ */
+export function execFileSync(file: string, argsOrOptions?: object | string[], options?: object): string | Buffer {
+  return node_child_process.execFileSync(
+    file,
+    !!options ? argsOrOptions : undefined,
+    !!options ? options : argsOrOptions,
+  );
+}
+
+/**
+ * Spawn and execute a command in a child process, synchronously.
+ *
+ * @param file File to execute
+ * @param argsOrOptions Arguments or options to apply to the command, if desired
+ * @param options Options to apply to the command, if desired
+ * @return Child process execution result object.
+ */
+export function spawnSync(command: string, argsOrOptions?: object | string[], options?: object): {
+  pid: number;
+  output: Array<Buffer | string>;
+  stdout: Buffer | string;
+  stderr: Buffer | string;
+  status: number | null;
+  signal: string | null;
+  error: Error | null;
+} {
+  return node_child_process.spawnSync(
+    command,
+    !!options ? argsOrOptions : undefined,
+    !!options ? options : argsOrOptions,
+  );
+}