inspector: open add `SymbolDispose`

PR-URL: https://github.com/nodejs/node/pull/48765
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>

doc/api/inspector.md

@@ -419,12 +419,20 @@ console.
 
 ### `inspector.open([port[, host[, wait]]])`
 
+<!-- YAML
+changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/48765
+    description: inspector.open() now returns a `Disposable` object.
+-->
+
 * `port` {number} Port to listen on for inspector connections. Optional.
   **Default:** what was specified on the CLI.
 * `host` {string} Host to listen on for inspector connections. Optional.
   **Default:** what was specified on the CLI.
 * `wait` {boolean} Block until a client has connected. Optional.
   **Default:** `false`.
+* Returns: {Disposable} that calls [`inspector.close()`][].
 
 Activate inspector on host and port. Equivalent to
 `node --inspect=[[host:]port]`, but can be done programmatically after node has
@@ -472,5 +480,6 @@ An exception will be thrown if there is no active inspector.
 [Chrome DevTools Protocol Viewer]: https://chromedevtools.github.io/devtools-protocol/v8/
 [Heap Profiler]: https://chromedevtools.github.io/devtools-protocol/v8/HeapProfiler
 [`'Debugger.paused'`]: https://chromedevtools.github.io/devtools-protocol/v8/Debugger#event-paused
+[`inspector.close()`]: #inspectorclose
 [`session.connect()`]: #sessionconnect
 [security warning]: cli.md#warning-binding-inspector-to-a-public-ipport-combination-is-insecure

lib/inspector.js

@@ -5,6 +5,7 @@ const {
   JSONStringify,
   SafeMap,
   Symbol,
+  SymbolDispose,
 } = primordials;
 
 const {
@@ -181,6 +182,8 @@ function inspectorOpen(port, host, wait) {
   open(port, host);
   if (wait)
     waitForDebugger();
+
+  return { __proto__: null, [SymbolDispose]() { _debugEnd(); } };
 }
 
 /**

test/parallel/test-inspector-open-dispose.mjs

@@ -0,0 +1,76 @@
+import * as common from '../common/index.mjs';
+import assert from 'node:assert';
+import net from 'node:net';
+import url from 'node:url';
+import { fork } from 'node:child_process';
+
+common.skipIfInspectorDisabled();
+if (process.env.BE_CHILD) {
+  await beChild();
+} else {
+  let firstPort;
+
+  const filename = url.fileURLToPath(import.meta.url);
+  const child = fork(filename, { env: { ...process.env, BE_CHILD: 1 } });
+
+  child.once('message', common.mustCall((msg) => {
+    assert.strictEqual(msg.cmd, 'started');
+
+    child.send({ cmd: 'open', args: [] });
+    child.once('message', common.mustCall(wasOpenedHandler));
+  }));
+
+  function wasOpenedHandler(msg) {
+    assert.strictEqual(msg.cmd, 'url');
+    const port = url.parse(msg.url).port;
+    ping(port, common.mustSucceed(() => {
+      // Inspector is already open, and won't be reopened, so args don't matter.
+      child.send({ cmd: 'dispose' });
+      child.once('message', common.mustCall(wasDisposedWhenOpenHandler));
+      firstPort = port;
+    }));
+  }
+
+  function wasDisposedWhenOpenHandler(msg) {
+    assert.strictEqual(msg.cmd, 'url');
+    assert.strictEqual(msg.url, undefined);
+    ping(firstPort, (err) => {
+      assert(err);
+      child.send({ cmd: 'dispose' });
+      child.once('message', common.mustCall(wasReDisposedHandler));
+    });
+  }
+
+  function wasReDisposedHandler(msg) {
+    assert.strictEqual(msg.cmd, 'url');
+    assert.strictEqual(msg.url, undefined);
+    process.exit();
+  }
+}
+
+function ping(port, callback) {
+  net.connect({ port, family: 4 })
+    .on('connect', function() { close(this); })
+    .on('error', function(err) { close(this, err); });
+
+  function close(self, err) {
+    self.end();
+    self.on('close', () => callback(err));
+  }
+}
+
+async function beChild() {
+  const inspector = await import('node:inspector');
+  let inspectorDisposer;
+  process.send({ cmd: 'started' });
+
+  process.on('message', (msg) => {
+    if (msg.cmd === 'open') {
+      inspectorDisposer = inspector.open(0, false, undefined);
+    }
+    if (msg.cmd === 'dispose') {
+      inspectorDisposer[Symbol.dispose]();
+    }
+    process.send({ cmd: 'url', url: inspector.url() });
+  });
+}