test_runner: use v8.serialize instead of TAP

doc/api/cli.md

@@ -2321,7 +2321,8 @@ on unsupported platforms will not be fixed.
 ### `NODE_TEST_CONTEXT=value`
 
 If `value` equals `'child'`, test reporter options will be overridden and test
-output will be sent to stdout in the TAP format.
+output will be sent to stdout in the TAP format. If any other value is provided,
+Node.js makes no guarantees about the reporter format used or its stability.
 
 ### `NODE_TLS_REJECT_UNAUTHORIZED=value`
 

lib/internal/error_serdes.js

@@ -13,19 +13,24 @@ const {
   ObjectGetOwnPropertyNames,
   ObjectGetPrototypeOf,
   ObjectKeys,
+  ObjectPrototypeHasOwnProperty,
   ObjectPrototypeToString,
   RangeError,
   ReferenceError,
   SafeSet,
   SymbolToStringTag,
   SyntaxError,
+  SymbolFor,
   TypeError,
   URIError,
 } = primordials;
+const { inspect: { custom: customInspectSymbol } } = require('util');
 
 const kSerializedError = 0;
 const kSerializedObject = 1;
 const kInspectedError = 2;
+const kInspectedSymbol = 3;
+const kCustomInspecteObject = 4;
 
 const errors = {
   Error, TypeError, RangeError, URIError, SyntaxError, ReferenceError, EvalError,
@@ -52,7 +57,13 @@ function TryGetAllProperties(object, target = object) {
         // Continue regardless of error.
       }
     }
-    if ('value' in descriptor && typeof descriptor.value !== 'function') {
+    if (key === 'cause') {
+      delete descriptor.get;
+      delete descriptor.set;
+      descriptor.value = serializeError(descriptor.value);
+      all[key] = descriptor;
+    } else if ('value' in descriptor &&
+            typeof descriptor.value !== 'function' && typeof descriptor.value !== 'symbol') {
       delete descriptor.get;
       delete descriptor.set;
       all[key] = descriptor;
@@ -95,6 +106,10 @@ function inspect(...args) {
 let serialize;
 function serializeError(error) {
   if (!serialize) serialize = require('v8').serialize;
+  if (typeof error === 'symbol') {
+    return Buffer.concat([Buffer.from([kInspectedSymbol]),
+                          Buffer.from(inspect(error), 'utf8')]);
+  }
   try {
     if (typeof error === 'object' &&
         ObjectPrototypeToString(error) === '[object Error]') {
@@ -113,6 +128,15 @@ function serializeError(error) {
   } catch {
     // Continue regardless of error.
   }
+  try {
+    if (error != null &&
+      ObjectPrototypeHasOwnProperty(error, customInspectSymbol)) {
+      return Buffer.concat([Buffer.from([kCustomInspecteObject]),
+                            Buffer.from(inspect(error), 'utf8')]);
+    }
+  } catch {
+    // Continue regardless of error.
+  }
   try {
     const serialized = serialize(error);
     return Buffer.concat([Buffer.from([kSerializedObject]), serialized]);
@@ -123,6 +147,12 @@ function serializeError(error) {
                         Buffer.from(inspect(error), 'utf8')]);
 }
 
+function fromBuffer(error) {
+  return Buffer.from(error.buffer,
+                     error.byteOffset + 1,
+                     error.byteLength - 1);
+}
+
 let deserialize;
 function deserializeError(error) {
   if (!deserialize) deserialize = require('v8').deserialize;
@@ -132,19 +162,27 @@ function deserializeError(error) {
       const ctor = errors[constructor];
       ObjectDefineProperty(properties, SymbolToStringTag, {
         __proto__: null,
-        value: { value: 'Error', configurable: true },
+        value: { __proto__: null, value: 'Error', configurable: true },
         enumerable: true,
       });
+      if ('cause' in properties && 'value' in properties.cause) {
+        properties.cause.value = deserializeError(properties.cause.value);
+      }
       return ObjectCreate(ctor.prototype, properties);
     }
     case kSerializedObject:
       return deserialize(error.subarray(1));
-    case kInspectedError: {
-      const buf = Buffer.from(error.buffer,
-                              error.byteOffset + 1,
-                              error.byteLength - 1);
-      return buf.toString('utf8');
+    case kInspectedError:
+      return fromBuffer(error).toString('utf8');
+    case kInspectedSymbol: {
+      const buf = fromBuffer(error);
+      return SymbolFor(buf.toString('utf8').substring('Symbol('.length, buf.length - 1));
     }
+    case kCustomInspecteObject:
+      return {
+        __proto__: null,
+        [customInspectSymbol]: () => fromBuffer(error).toString('utf8'),
+      };
   }
   require('assert').fail('This should not happen');
 }

lib/internal/test_runner/reporter/v8.js

@@ -0,0 +1,36 @@
+'use strict';
+
+const { DefaultSerializer } = require('v8');
+const { Buffer } = require('buffer');
+const { serializeError } = require('internal/error_serdes');
+
+
+module.exports = async function* v8Reporter(source) {
+  const serializer = new DefaultSerializer();
+
+  for await (const item of source) {
+    const originalError = item.data.details?.error;
+    if (originalError) {
+      item.data.details.error = serializeError(originalError);
+    }
+    // Add 4 bytes, to later populate with message length
+    serializer.writeRawBytes(Buffer.allocUnsafe(4));
+    serializer.writeHeader();
+    serializer.writeValue(item);
+
+    if (originalError) {
+      item.data.details.error = originalError;
+    }
+
+    const serializedMessage = serializer.releaseBuffer();
+    const serializedMessageLength = serializedMessage.length - 4;
+
+    serializedMessage.set([
+      serializedMessageLength >> 24 & 0xFF,
+      serializedMessageLength >> 16 & 0xFF,
+      serializedMessageLength >> 8 & 0xFF,
+      serializedMessageLength & 0xFF,
+    ], 0);
+    yield serializedMessage;
+  }
+};