debugger: fix event listener leak in the run command

It should remove both the error and the ready event listeners attached when either of them fires, instead of removing only the one whose corresponding event fires, otherwise the other event listener will always get leaked.
nodejs-github-bot · Nov 7, 2025 · Oct 28, 2025 · Oct 29, 2025 · Nov 1, 2025 · Oct 28, 2025
commit 5ff338f4d8f9d26bc5bd4480ceeb2b3e482f08e5
diff --git a/lib/internal/debugger/inspect_client.js b/lib/internal/debugger/inspect_client.js
@@ -344,8 +344,20 @@ class Client extends EventEmitter {
     };
 
     return new Promise((resolve, reject) => {
-      this.once('error', reject);
-      this.once('ready', resolve);
+      const tearDown = () => {
+        this.removeListener('ready', onReady);
+        this.removeListener('error', onError);
+      };
+      const onError = (err) => {
+        tearDown();
+        reject(err);
+      };
+      const onReady = () => {
+        tearDown();
+        resolve();
+      };
+      this.once('error', onError);
+      this.once('ready', onReady);
 
       httpReq.on('upgrade', handshakeListener);
       httpReq.end();

diff --git a/test/common/debugger.js b/test/common/debugger.js
@@ -141,6 +141,10 @@ function startCLI(args, flags = [], spawnOpts = {}, opts = { randomPort: true })
       return getOutput();
     },
 
+    get stderrOutput() {
+      return stderrOutput;
+    },
+
     get rawOutput() {
       return outputBuffer.join('').toString();
     },

diff --git a/test/parallel/test-debugger-restart-message.js b/test/parallel/test-debugger-restart-message.js
@@ -31,6 +31,8 @@ const startCLI = require('../common/debugger');
     } finally {
       await cli.quit();
     }
+
+    assert.doesNotMatch(cli.stderrOutput, /MaxListenersExceededWarning/);
   }
 
   onWaitForInitialBreak();