1 files changed, 53 insertions, 0 deletions
diff --git a/test/parallel/test-inspector-port-zero.js b/test/parallel/test-inspector-port-zero.js
new file mode 100644
index 0000000000..a3eb08e5fb
--- /dev/null
+++ b/test/parallel/test-inspector-port-zero.js
@@ -0,0 +1,53 @@
+'use strict';
+const { mustCall, skipIfInspectorDisabled } = require('../common');
+
+skipIfInspectorDisabled();
+
+const assert = require('assert');
+const { URL } = require('url');
+const { spawn } = require('child_process');
+
+function test(arg, port = '') {
+  const args = [arg, '-p', 'process.debugPort'];
+  const proc = spawn(process.execPath, args);
+  proc.stdout.setEncoding('utf8');
+  proc.stderr.setEncoding('utf8');
+  let stdout = '';
+  let stderr = '';
+  proc.stdout.on('data', (data) => stdout += data);
+  proc.stderr.on('data', (data) => stderr += data);
+  proc.stdout.on('close', assert.ifError);
+  proc.stderr.on('close', assert.ifError);
+  proc.stderr.on('data', () => {
+    if (!stderr.includes('\n')) return;
+    assert(/Debugger listening on (.+)/.test(stderr));
+    port = new URL(RegExp.$1).port;
+    assert(+port > 0);
+  });
+  if (/inspect-brk/.test(arg)) {
+    proc.stderr.on('data', () => {
+      if (stderr.includes('\n') && !proc.killed) proc.kill();
+    });
+  } else {
+    let onclose = () => {
+      onclose = () => assert.strictEqual(port, stdout.trim());
+    };
+    proc.stdout.on('close', mustCall(() => onclose()));
+    proc.stderr.on('close', mustCall(() => onclose()));
+    proc.on('exit', mustCall((exitCode) => assert.strictEqual(exitCode, 0)));
+  }
+}
+
+test('--inspect=0');
+test('--inspect=127.0.0.1:0');
+test('--inspect=localhost:0');
+
+test('--inspect-brk=0');
+test('--inspect-brk=127.0.0.1:0');
+test('--inspect-brk=localhost:0');
+
+// In these cases, the inspector doesn't listen, so an ephemeral port is not
+// allocated and the expected value of `process.debugPort` is `0`.
+test('--inspect-port=0', '0');
+test('--inspect-port=127.0.0.1:0', '0');
+test('--inspect-port=localhost:0', '0');