replace symbol uncaughtExceptionMonitor by a string

doc/api/process.md

@@ -263,18 +263,8 @@ console.log('This will not run.');
 ```
 
 It is possible to monitor `'uncaughtException'` events without overriding the
-default behavior to exit the process by installing a listener using the symbol
-`uncaughtExceptionMonitor`.
-
-```js
-process.on(process.uncaughtExceptionMonitor, (err, origin) => {
-  MyMonitoringTool.logSync(err, origin);
-});
-
-// Intentionally cause an exception, but don't catch it.
-nonexistentFunc();
-// Still crashes Node.js
-```
+default behavior to exit the process by installing a
+`'uncaughtExceptionMonitor'` listener.
 
 #### Warning: Using `'uncaughtException'` correctly
 
@@ -303,6 +293,34 @@ To restart a crashed application in a more reliable way, whether
 in a separate process to detect application failures and recover or restart as
 needed.
 
+### Event: `'uncaughtExceptionMonitor'`
+<!-- YAML
+added: REPLACEME
+-->
+
+* `err` {Error} The uncaught exception.
+* `origin` {string} Indicates if the exception originates from an unhandled
+  rejection or from synchronous errors. Can either be `'uncaughtException'` or
+  `'unhandledRejection'`.
+
+The `'uncaughtExceptionMonitor'` event is emitted before an
+`'uncaughtException'` event is emitted or a hook installed via
+[`process.setUncaughtExceptionCaptureCallback()`][] is called.
+
+Installing a `'uncaughtExceptionMonitor'` listener does not change the behavior
+once an `'uncaughtException'` event is emitted, therefore the process will
+still crash if no regular `'uncaughtException'` listener is installed.
+
+```js
+process.on('uncaughtExceptionMonitor', (err, origin) => {
+  MyMonitoringTool.logSync(err, origin);
+});
+
+// Intentionally cause an exception, but don't catch it.
+nonexistentFunc();
+// Still crashes Node.js
+```
+
 ### Event: `'unhandledRejection'`
 <!-- YAML
 added: v1.4.1
@@ -2334,20 +2352,6 @@ documentation for the [`'warning'` event][process_warning] and the
 [`emitWarning()` method][process_emit_warning] for more information about this
 flag's behavior.
 
-## `process.uncaughtExceptionMonitor`
-<!-- YAML
-added: REPLACEME
--->
-
-This symbol shall be used to install a listener for only monitoring
-`'uncaughtException'` events. Listeners installed using this symbol are called
-before the regular `'uncaughtException'` listeners and before a hook
-installed via [`process.setUncaughtExceptionCaptureCallback()`][].
-
-Installing a listener using this symbol does not change the behavior once an
-`'uncaughtException'` event is emitted, therefore the process will still crash
-if no regular `'uncaughtException'` listener is installed.
-
 ## `process.umask([mask])`
 <!-- YAML
 added: v0.1.19

lib/internal/bootstrap/node.js

@@ -206,8 +206,7 @@ ObjectDefineProperty(process, 'features', {
   const {
     onGlobalUncaughtException,
     setUncaughtExceptionCaptureCallback,
-    hasUncaughtExceptionCaptureCallback,
-    kUncaughtExceptionMonitor
+    hasUncaughtExceptionCaptureCallback
   } = require('internal/process/execution');
 
   // For legacy reasons this is still called `_fatalException`, even
@@ -221,12 +220,6 @@ ObjectDefineProperty(process, 'features', {
     setUncaughtExceptionCaptureCallback;
   process.hasUncaughtExceptionCaptureCallback =
     hasUncaughtExceptionCaptureCallback;
-  ObjectDefineProperty(process, 'uncaughtExceptionMonitor', {
-    value: kUncaughtExceptionMonitor,
-    writable: false,
-    configurable: true,
-    enumerable: true
-  });
 }
 
 const { emitWarning } = require('internal/process/warning');

lib/internal/process/execution.js

@@ -3,7 +3,6 @@
 const {
   JSONStringify,
   PromiseResolve,
-  Symbol,
 } = primordials;
 
 const path = require('path');
@@ -28,8 +27,6 @@ const {
 // communication with JS.
 const { shouldAbortOnUncaughtToggle } = internalBinding('util');
 
-const kUncaughtExceptionMonitor = Symbol('process.uncaughtExceptionMonitor');
-
 function tryGetCwd() {
   try {
     return process.cwd();
@@ -162,7 +159,7 @@ function createOnGlobalUncaughtException() {
     }
 
     const type = fromPromise ? 'unhandledRejection' : 'uncaughtException';
-    process.emit(kUncaughtExceptionMonitor, er, type);
+    process.emit('uncaughtExceptionMonitor', er, type);
     if (exceptionHandlerState.captureFn !== null) {
       exceptionHandlerState.captureFn(er);
     } else if (!process.emit('uncaughtException', er, type)) {
@@ -218,6 +215,5 @@ module.exports = {
   evalScript,
   onGlobalUncaughtException: createOnGlobalUncaughtException(),
   setUncaughtExceptionCaptureCallback,
-  hasUncaughtExceptionCaptureCallback,
-  kUncaughtExceptionMonitor
+  hasUncaughtExceptionCaptureCallback
 };

test/fixtures/uncaught-exceptions/uncaught-monitor.js

@@ -3,7 +3,7 @@
 // Keep the event loop alive.
 setTimeout(() => {}, 1e6);
 
-process.on(process.uncaughtExceptionMonitor, (err) => {
+process.on('uncaughtExceptionMonitor', (err) => {
   console.log(`Monitored: ${err.message}`);
 });
 

test/parallel/test-process-uncaught-exception-monitor.js

@@ -25,7 +25,7 @@ const fixtures = require('../common/fixtures');
 const theErr = new Error('MyError');
 
 process.on(
-  process.uncaughtExceptionMonitor,
+  'uncaughtExceptionMonitor',
   common.mustCall((err, origin) => {
     assert.strictEqual(err, theErr);
     assert.strictEqual(origin, 'uncaughtException');