err-code - npm Package Compare versions

Comparing version 2.0.1 to 2.0.2

.eslintrc.json

 {
     "root": true,
     "extends": [
-        "@satazor/eslint-config/es5",
+        "@satazor/eslint-config/es6",
         "@satazor/eslint-config/addons/node"
     ]
 }

index.js

 'use strict';
 
-function maybeDefineProperty(obj, name, value) {
-    var descriptor;
-
-    if (Object.isFrozen(obj)) {
-        return;
+function assign(obj, props) {
+    for (const key in props) {
+        Object.defineProperty(obj, key, {
+            value: props[key],
+            enumerable: true,
+            configurable: true,
+        });
     }
 
-    descriptor = Object.getOwnPropertyDescriptor(obj, name);
-
-    if (descriptor && !descriptor.writable) {
-        return;
-    }
-
-    obj[name] = value;
+    return obj;
 }
 
 function createError(err, code, props) {
-    var key;
-
     if (!(err instanceof Error)) {
@@ -26,17 +20,29 @@ throw new TypeError('Please pass an Error to err-code');
 
+    if (!props) {
+        props = {};
+    }
+
     if (typeof code === 'object') {
         props = code;
-    } else if (code != null) {
-        maybeDefineProperty(err, 'code', code);
+        code = undefined;
     }
 
-    if (props) {
-        for (key in props) {
-            maybeDefineProperty(err, key, props[key]);
-        }
+    if (code != null) {
+        props.code = code;
     }
 
-    return err;
+    try {
+        return assign(err, props);
+    } catch (_) {
+        props.message = err.message;
+        props.stack = err.stack;
+
+        const ErrClass = function () {};
+
+        ErrClass.prototype = Object.create(Object.getPrototypeOf(err));
+
+        return assign(new ErrClass(), props);
+    }
 }
 
 module.exports = createError;

index.umd.js

 (function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.errCode = f()}})(function(){var define,module,exports;return (function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
 'use strict';
 
-function maybeDefineProperty(obj, name, value) {
-    var descriptor;
-
-    if (Object.isFrozen(obj)) {
-        return;
+function assign(obj, props) {
+    for (const key in props) {
+        Object.defineProperty(obj, key, {
+            value: props[key],
+            enumerable: true,
+            configurable: true,
+        });
     }
 
-    descriptor = Object.getOwnPropertyDescriptor(obj, name);
-
-    if (descriptor && !descriptor.writable) {
-        return;
-    }
-
-    obj[name] = value;
+    return obj;
 }
 
 function createError(err, code, props) {
-    var key;
-
     if (!(err instanceof Error)) {
@@ -27,15 +21,27 @@ throw new TypeError('Please pass an Error to err-code');
 
+    if (!props) {
+        props = {};
+    }
+
     if (typeof code === 'object') {
         props = code;
-    } else if (code != null) {
-        maybeDefineProperty(err, 'code', code);
+        code = undefined;
     }
 
-    if (props) {
-        for (key in props) {
-            maybeDefineProperty(err, key, props[key]);
-        }
+    if (code != null) {
+        props.code = code;
     }
 
-    return err;
+    try {
+        return assign(err, props);
+    } catch (_) {
+        props.message = err.message;
+        props.stack = err.stack;
+
+        const ErrClass = function () {};
+
+        ErrClass.prototype = Object.create(Object.getPrototypeOf(err));
+
+        return assign(new ErrClass(), props);
+    }
 }
@@ -42,0 +48,0 @@

package.json

 {
   "name": "err-code",
-  "version": "2.0.1",
+  "version": "2.0.2",
   "description": "Create an error with a code",
@@ -5,0 +5,0 @@ "main": "index.js",

README.md

@@ -60,3 +60,3 @@ # err-code
 
-If the passed `Error` already has a `.code` field, or fields specified in the third argument to `errcode` they will be overwritten, unless the fields have been [defined as read-only](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty) or the `Error` object has been [frozen](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze).
+If the passed `Error` already has a `.code` field, or fields specified in the third argument to `errcode` they will be overwritten, unless the fields are read only or otherwise throw during assignment in which case a new object will be created that shares a prototype chain with the original `Error`. The `.stack` and `.message` properties will be carried over from the original error and `.code` or any passed properties will be set on it.
 
@@ -63,0 +63,0 @@

test/test.js

 'use strict';
 
-var errcode = require('../index');
-var expect = require('expect.js');
+const errcode = require('../index');
+const expect = require('expect.js');
 
-describe('errcode', function () {
-    describe('string as first argument', function () {
-        it('should throw an error', function () {
-            expect(function () { errcode('my message'); }).to.throwError(function (err) {
+describe('errcode', () => {
+    describe('string as first argument', () => {
+        it('should throw an error', () => {
+            expect(() => { errcode('my message'); }).to.throwError((err) => {
                 expect(err).to.be.a(TypeError);
@@ -15,6 +15,6 @@ });
 
-    describe('error as first argument', function () {
-        it('should accept an error and do nothing', function () {
-            var myErr = new Error('my message');
-            var err = errcode(myErr);
+    describe('error as first argument', () => {
+        it('should accept an error and do nothing', () => {
+            const myErr = new Error('my message');
+            const err = errcode(myErr);
 
@@ -25,5 +25,5 @@ expect(err).to.be(myErr);
 
-        it('should accept an error and add a code', function () {
-            var myErr = new Error('my message');
-            var err = errcode(myErr, 'ESOME');
+        it('should accept an error and add a code', () => {
+            const myErr = new Error('my message');
+            const err = errcode(myErr, 'ESOME');
 
@@ -34,5 +34,5 @@ expect(err).to.be(myErr);
 
-        it('should accept an error object and add code & properties', function () {
-            var myErr = new Error('my message');
-            var err = errcode(myErr, 'ESOME', { foo: 'bar', bar: 'foo' });
+        it('should accept an error object and add code & properties', () => {
+            const myErr = new Error('my message');
+            const err = errcode(myErr, 'ESOME', { foo: 'bar', bar: 'foo' });
 
@@ -45,5 +45,5 @@ expect(err).to.be.an(Error);
 
-        it('should create an error object without code but with properties', function () {
-            var myErr = new Error('my message');
-            var err = errcode(myErr, { foo: 'bar', bar: 'foo' });
+        it('should create an error object without code but with properties', () => {
+            const myErr = new Error('my message');
+            const err = errcode(myErr, { foo: 'bar', bar: 'foo' });
 
@@ -56,5 +56,4 @@ expect(err).to.be.an(Error);
 
-        it('should not attempt to set non-writable field', function () {
-            var myErr = new Error('my message');
-            var err;
+        it('should set a non-writable field', () => {
+            const myErr = new Error('my message');
 
@@ -65,20 +64,83 @@ Object.defineProperty(myErr, 'code', {
             });
-            err = errcode(myErr, 'ERR_WAT');
+            const err = errcode(myErr, 'ERR_WAT');
 
             expect(err).to.be.an(Error);
-            expect(err.code).to.be('derp');
+            expect(err.stack).to.equal(myErr.stack);
+            expect(err.code).to.be('ERR_WAT');
         });
 
-        it('should not add code to frozen object', function () {
-            var myErr = new Error('my message');
-            var err = errcode(Object.freeze(myErr), 'ERR_WAT');
+        it('should add a code to frozen object', () => {
+            const myErr = new Error('my message');
+            const err = errcode(Object.freeze(myErr), 'ERR_WAT');
 
             expect(err).to.be.an(Error);
-            expect(err.code).to.be(undefined);
+            expect(err.stack).to.equal(myErr.stack);
+            expect(err.code).to.be('ERR_WAT');
         });
+
+        it('should to set a field that throws at assignment time', () => {
+            const myErr = new Error('my message');
+
+            Object.defineProperty(myErr, 'code', {
+                enumerable: true,
+                set() {
+                    throw new Error('Nope!');
+                },
+                get() {
+                    return 'derp';
+                },
+            });
+            const err = errcode(myErr, 'ERR_WAT');
+
+            expect(err).to.be.an(Error);
+            expect(err.stack).to.equal(myErr.stack);
+            expect(err.code).to.be('ERR_WAT');
+        });
+
+        it('should retain error type', () => {
+            const myErr = new TypeError('my message');
+
+            Object.defineProperty(myErr, 'code', {
+                value: 'derp',
+                writable: false,
+            });
+            const err = errcode(myErr, 'ERR_WAT');
+
+            expect(err).to.be.a(TypeError);
+            expect(err.stack).to.equal(myErr.stack);
+            expect(err.code).to.be('ERR_WAT');
+        });
+
+        it('should add a code to a class that extends Error', () => {
+            class CustomError extends Error {
+                set code(val) {
+                    throw new Error('Nope!');
+                }
+            }
+
+            const myErr = new CustomError('my message');
+
+            Object.defineProperty(myErr, 'code', {
+                value: 'derp',
+                writable: false,
+                configurable: false,
+            });
+            const err = errcode(myErr, 'ERR_WAT');
+
+            expect(err).to.be.a(CustomError);
+            expect(err.stack).to.equal(myErr.stack);
+            expect(err.code).to.be('ERR_WAT');
+
+            // original prototype chain should be intact
+            expect(() => {
+                const otherErr = new CustomError('my message');
+
+                otherErr.code = 'derp';
+            }).to.throwError();
+        });
     });
 
-    describe('falsy first arguments', function () {
-        it('should not allow passing null as the first argument', function () {
-            expect(function () { errcode(null); }).to.throwError(function (err) {
+    describe('falsy first arguments', () => {
+        it('should not allow passing null as the first argument', () => {
+            expect(() => { errcode(null); }).to.throwError((err) => {
                 expect(err).to.be.a(TypeError);
@@ -88,4 +150,4 @@ });
 
-        it('should not allow passing undefined as the first argument', function () {
-            expect(function () { errcode(undefined); }).to.throwError(function (err) {
+        it('should not allow passing undefined as the first argument', () => {
+            expect(() => { errcode(undefined); }).to.throwError((err) => {
                 expect(err).to.be.a(TypeError);
@@ -92,0 +154,0 @@ });

No alert changes

Improved metrics

Total package byte prevSize

11990

increased by23.08%

Lines of code

239

increased by35.03%

No dependency changes