lib: properly processing JavaScript exceptions on async_hooks fatal error

JavaScript exceptions could be arbitrary values.

Author: legendecas

lib/internal/async_hooks.js

@@ -100,6 +100,9 @@ const {
 const { async_id_symbol,
         trigger_async_id_symbol } = internalBinding('symbols');
 
+// Lazy load of internal/util/inspect;
+let inspect;
+
 // Used in AsyncHook and AsyncResource.
 const init_symbol = Symbol('init');
 const before_symbol = Symbol('before');
@@ -156,12 +159,20 @@ function executionAsyncResource() {
   return lookupPublicResource(resource);
 }
 
+function inspectExceptionValue(e) {
+  if (inspect == null) {
+    inspect = require('internal/util/inspect').inspect;
+  }
+  const o = { message: inspect(e) };
+  return o;
+}
+
 // Used to fatally abort the process if a callback throws.
 function fatalError(e) {
-  if (typeof e.stack === 'string') {
+  if (e !== null && typeof e === 'object' && typeof e.stack === 'string') {
     process._rawDebug(e.stack);
   } else {
-    const o = { message: e };
+    const o = inspectExceptionValue(e);
     ErrorCaptureStackTrace(o, fatalError);
     process._rawDebug(o.stack);
   }

test/parallel/test-async-hooks-fatal-error.js

@@ -0,0 +1,52 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+const childProcess = require('child_process');
+
+if (process.argv[2] === 'child') {
+  child(process.argv[3], process.argv[4]);
+} else {
+  main();
+}
+
+function child(type, valueType) {
+  const { createHook } = require('async_hooks');
+  const fs = require('fs');
+
+  createHook({
+    [type]() {
+      if (valueType === 'symbol') {
+        throw Symbol('foo');
+      }
+      // eslint-disable-next-line no-throw-literal
+      throw null;
+    }
+  }).enable();
+
+  // Trigger `promiseResolve`.
+  new Promise((resolve) => resolve())
+  // Trigger `after`/`destroy`.
+    .then(() => fs.promises.readFile(__filename, 'utf8'))
+  // Make process exit with code 0 if no error caught.
+    .then(() => process.exit(0));
+}
+
+function main() {
+  const types = [ 'init', 'before', 'after', 'destroy', 'promiseResolve' ];
+  const valueTypes = [
+    [ 'null', 'Error: null' ],
+    [ 'symbol', 'Error: Symbol(foo)' ],
+  ];
+  for (const type of types) {
+    for (const [valueType, expect] of valueTypes) {
+      const cp = childProcess.spawnSync(
+        process.execPath,
+        [ __filename, 'child', type, valueType ],
+        {
+          encoding: 'utf8',
+        });
+      assert.strictEqual(cp.status, 1, type);
+      assert.strictEqual(cp.stderr.trim().split('\n')[0], expect, type);
+    }
+  }
+}