errors: make sure all Node.js errors show their properties

This improves Node.js errors by always showing the attached properties
when inspecting such an error. This applies especially to SystemError.
It did often not show any properties but now all properties will be
visible.

This is done in a mainly backwards compatible way. Instead of using
prototype getters and setters, the property is now set directly on the
error.

PR-URL: #29677
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Benjamin Gruenbaum <[email protected]>

Author: BridgeAR

lib/internal/errors.js

@@ -12,8 +12,6 @@
 
 const { Object, Math } = primordials;
 
-const kCode = Symbol('code');
-const kInfo = Symbol('info');
 const messages = new Map();
 const codes = {};
 
@@ -121,76 +119,86 @@ class SystemError extends Error {
       writable: true,
       configurable: true
     });
-    Object.defineProperty(this, kInfo, {
-      configurable: false,
-      enumerable: false,
-      value: context
-    });
-    Object.defineProperty(this, kCode, {
-      configurable: true,
-      enumerable: false,
-      value: key,
-      writable: true
-    });
     addCodeToName(this, 'SystemError', key);
-  }
 
-  get code() {
-    return this[kCode];
-  }
+    this.code = key;
 
-  set code(value) {
-    Object.defineProperty(this, 'code', {
-      configurable: true,
+    Object.defineProperty(this, 'info', {
+      value: context,
       enumerable: true,
-      value,
-      writable: true
+      configurable: true,
+      writable: false
     });
-  }
-
-  get info() {
-    return this[kInfo];
-  }
 
-  get errno() {
-    return this[kInfo].errno;
-  }
-
-  set errno(val) {
-    this[kInfo].errno = val;
-  }
-
-  get syscall() {
-    return this[kInfo].syscall;
-  }
-
-  set syscall(val) {
-    this[kInfo].syscall = val;
-  }
-
-  get path() {
-    return this[kInfo].path !== undefined ?
-      this[kInfo].path.toString() : undefined;
-  }
+    Object.defineProperty(this, 'errno', {
+      get() {
+        return context.errno;
+      },
+      set: (value) => {
+        context.errno = value;
+      },
+      enumerable: true,
+      configurable: true
+    });
 
-  set path(val) {
-    this[kInfo].path = val ?
-      lazyBuffer().from(val.toString()) : undefined;
-  }
+    Object.defineProperty(this, 'syscall', {
+      get() {
+        return context.syscall;
+      },
+      set: (value) => {
+        context.syscall = value;
+      },
+      enumerable: true,
+      configurable: true
+    });
 
-  get dest() {
-    return this[kInfo].path !== undefined ?
-      this[kInfo].dest.toString() : undefined;
-  }
+    if (context.path !== undefined) {
+      // TODO(BridgeAR): Investigate why and when the `.toString()` was
+      // introduced. The `path` and `dest` properties in the context seem to
+      // always be of type string. We should probably just remove the
+      // `.toString()` and `Buffer.from()` operations and set the value on the
+      // context as the user did.
+      Object.defineProperty(this, 'path', {
+        get() {
+          return context.path != null ?
+            context.path.toString() : context.path;
+        },
+        set: (value) => {
+          context.path = value ?
+            lazyBuffer().from(value.toString()) : undefined;
+        },
+        enumerable: true,
+        configurable: true
+      });
+    }
 
-  set dest(val) {
-    this[kInfo].dest = val ?
-      lazyBuffer().from(val.toString()) : undefined;
+    if (context.dest !== undefined) {
+      Object.defineProperty(this, 'dest', {
+        get() {
+          return context.dest != null ?
+            context.dest.toString() : context.dest;
+        },
+        set: (value) => {
+          context.dest = value ?
+            lazyBuffer().from(value.toString()) : undefined;
+        },
+        enumerable: true,
+        configurable: true
+      });
+    }
   }
 
   toString() {
     return `${this.name} [${this.code}]: ${this.message}`;
   }
+
+  [Symbol.for('nodejs.util.inspect.custom')](recurseTimes, ctx) {
+    return lazyInternalUtilInspect().inspect(this, {
+      ...ctx,
+      getters: true,
+      customInspect: false
+    });
+  }
 }
 
 function makeSystemErrorWithCode(key) {
@@ -221,19 +229,7 @@ function makeNodeErrorWithCode(Base, key) {
         configurable: true
       });
       addCodeToName(this, super.name, key);
-    }
-
-    get code() {
-      return key;
-    }
-
-    set code(value) {
-      Object.defineProperty(this, 'code', {
-        configurable: true,
-        enumerable: true,
-        value,
-        writable: true
-      });
+      this.code = key;
     }
 
     toString() {
@@ -394,7 +390,6 @@ function uvException(ctx) {
     err[prop] = ctx[prop];
   }
 
-  // TODO(BridgeAR): Show the `code` property as part of the stack.
   err.code = code;
   if (path) {
     err.path = path;

test/message/internal_assert.out

@@ -12,4 +12,6 @@ Please open an issue with this stack trace at https://github.com/nodejs/node/iss
     at *
     at *
     at *
-    at *
+    at * {
+  code: 'ERR_INTERNAL_ASSERTION'
+}

test/message/internal_assert_fail.out

@@ -13,4 +13,6 @@ Please open an issue with this stack trace at https://github.com/nodejs/node/iss
     at *
     at *
     at *
-    at *
+    at * {
+  code: 'ERR_INTERNAL_ASSERTION'
+}

test/parallel/test-dgram-socket-buffer-size.js

@@ -4,6 +4,7 @@
 const common = require('../common');
 const assert = require('assert');
 const dgram = require('dgram');
+const { inspect } = require('util');
 const { SystemError } = require('internal/errors');
 const { internalBinding } = require('internal/test/binding');
 const {
@@ -22,7 +23,7 @@ function getExpectedError(type) {
     'ENOTSOCK (socket operation on non-socket)' : 'EBADF (bad file descriptor)';
   const error = {
     code: 'ERR_SOCKET_BUFFER_SIZE',
-    type: SystemError,
+    name: 'SystemError',
     message: `Could not get or set buffer size: ${syscall} returned ${suffix}`,
     info: {
       code,
@@ -40,9 +41,25 @@ function getExpectedError(type) {
 
   const socket = dgram.createSocket('udp4');
 
-  common.expectsError(() => {
+  assert.throws(() => {
     socket.setSendBufferSize(8192);
-  }, errorObj);
+  }, (err) => {
+    assert.strictEqual(
+      inspect(err).replace(/^ +at .*\n/gm, ''),
+      `SystemError [ERR_SOCKET_BUFFER_SIZE]: ${errorObj.message}\n` +
+        "  code: 'ERR_SOCKET_BUFFER_SIZE',\n" +
+        '  info: {\n' +
+        `    errno: ${errorObj.info.errno},\n` +
+        `    code: '${errorObj.info.code}',\n` +
+        `    message: '${errorObj.info.message}',\n` +
+        `    syscall: '${errorObj.info.syscall}'\n` +
+        '  },\n' +
+        `  errno: [Getter/Setter: ${errorObj.info.errno}],\n` +
+        `  syscall: [Getter/Setter: '${errorObj.info.syscall}']\n` +
+        '}'
+    );
+    return true;
+  });
 
   common.expectsError(() => {
     socket.getSendBufferSize();

test/parallel/test-internal-errors.js

@@ -82,9 +82,9 @@ common.expectsError(() => {
 {
   const myError = new errors.codes.TEST_ERROR_1('foo');
   assert.strictEqual(myError.code, 'TEST_ERROR_1');
-  assert.strictEqual(myError.hasOwnProperty('code'), false);
+  assert.strictEqual(myError.hasOwnProperty('code'), true);
   assert.strictEqual(myError.hasOwnProperty('name'), false);
-  assert.deepStrictEqual(Object.keys(myError), []);
+  assert.deepStrictEqual(Object.keys(myError), ['code']);
   const initialName = myError.name;
   myError.code = 'FHQWHGADS';
   assert.strictEqual(myError.code, 'FHQWHGADS');
@@ -99,11 +99,11 @@ common.expectsError(() => {
 // browser. Note that `name` becomes enumerable after being assigned.
 {
   const myError = new errors.codes.TEST_ERROR_1('foo');
-  assert.deepStrictEqual(Object.keys(myError), []);
+  assert.deepStrictEqual(Object.keys(myError), ['code']);
   const initialToString = myError.toString();
 
   myError.name = 'Fhqwhgads';
-  assert.deepStrictEqual(Object.keys(myError), ['name']);
+  assert.deepStrictEqual(Object.keys(myError), ['code', 'name']);
   assert.notStrictEqual(myError.toString(), initialToString);
 }
 
@@ -114,7 +114,7 @@ common.expectsError(() => {
   let initialConsoleLog = '';
   hijackStdout((data) => { initialConsoleLog += data; });
   const myError = new errors.codes.TEST_ERROR_1('foo');
-  assert.deepStrictEqual(Object.keys(myError), []);
+  assert.deepStrictEqual(Object.keys(myError), ['code']);
   const initialToString = myError.toString();
   console.log(myError);
   assert.notStrictEqual(initialConsoleLog, '');
@@ -124,7 +124,7 @@ common.expectsError(() => {
   let subsequentConsoleLog = '';
   hijackStdout((data) => { subsequentConsoleLog += data; });
   myError.message = 'Fhqwhgads';
-  assert.deepStrictEqual(Object.keys(myError), []);
+  assert.deepStrictEqual(Object.keys(myError), ['code']);
   assert.notStrictEqual(myError.toString(), initialToString);
   console.log(myError);
   assert.strictEqual(subsequentConsoleLog, initialConsoleLog);

test/parallel/test-repl-top-level-await.js

@@ -161,8 +161,10 @@ async function ctrlCTest() {
   ]), [
     'await timeout(100000)\r',
     'Thrown:',
-    'Error [ERR_SCRIPT_EXECUTION_INTERRUPTED]: ' +
-      'Script execution was interrupted by `SIGINT`',
+    '[Error [ERR_SCRIPT_EXECUTION_INTERRUPTED]: ' +
+      'Script execution was interrupted by `SIGINT`] {',
+    "  code: 'ERR_SCRIPT_EXECUTION_INTERRUPTED'",
+    '}',
     PROMPT
   ]);
 }