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feat: create custom Error constructors
As a result of nodejs/node#33857, Node errors are no longer custom error classes and .constructor is a built-in Error constructor. Therefore, to support Node 15 and later, define Error constructors for the codes used by this module in this module, as done by readable-stream and other projects. Note: Much of the code is copied from lib/internal/errors.js @ v15.0.1. ESLint rules are relaxed to make it easier to minimize divergence and make updates easier. Signed-off-by: Kevin Locke <kevin@kevinlocke.name>
1 parent 27a64d5 commit 5f8d0bf

2 files changed

Lines changed: 262 additions & 58 deletions

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‎.eslintrc.json‎

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"node/shebang": "off"
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}
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},
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{
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"files": [
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"lib/errors.js"
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],
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"rules": {
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"comma-dangle": ["error", "only-multiline"],
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"curly": "off",
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"global-require": "off",
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"indent": "off",
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"new-cap": "off",
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"no-restricted-syntax": "off",
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"no-use-before-define": ["error", { "functions": false }],
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"nonblock-statement-body-position": ["error", "below"],
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"operator-linebreak": ["error", "after"],
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"unicorn/no-null": "off"
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}
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},
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{
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"files": [
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"lib/zlib-internal.js"

‎lib/errors.js‎

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@@ -1,73 +1,260 @@
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/**
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* Export error constructors (or work-alikes) from lib/internal/errors.js
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* Caller-visible Errors thrown by this module.
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*
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* These are ugly hacks. Hopefully the constructors will be exposed in a
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* future version: https://github.com/nodejs/node/issues/14554
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* Based on Node.js core errors in lib/internal/errors.js @ v15.0.1.
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*
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* Hopefully the constructors will be exposed in a future version:
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* https://github.com/nodejs/node/issues/14554
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*
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* Copies are already proliferating:
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* https://github.com/nodejs/readable-stream/blob/v3.6.0/errors.js
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* https://github.com/streamich/memfs/blob/v3.2.0/src/internal/errors.ts
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*
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* Looks like there was an attempt to create a standalone module:
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* https://github.com/jasnell/internal-errors
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*
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* @copyright Copyright Joyent, Inc. and other Node contributors.
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* @copyright Copyright 2020 Kevin Locke <kevin@kevinlocke.name>
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* @license MIT
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*/
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'use strict';
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const ArrayIsArray = Array.isArray;
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const ObjectDefineProperty = Object.defineProperty;
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const messages = new Map();
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const codes = exports;
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const classRegExp = /^([A-Z][a-z0-9]*)+$/;
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// Sorted by a rough estimate on most frequently used entries.
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const kTypes = [
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'string',
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'function',
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'number',
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'object',
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// Accept 'Function' and 'Object' as alternative to the lower cased version.
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'Function',
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'Object',
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'boolean',
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'bigint',
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'symbol'
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];
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let excludedStackFn;
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let internalUtilInspect = null;
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function lazyInternalUtilInspect() {
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if (!internalUtilInspect) {
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internalUtilInspect = require('util');
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}
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return internalUtilInspect;
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}
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const assert = require('assert');
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const { kMaxLength } = require('buffer');
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const { Readable, finished } = require('stream');
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const { Deflate, deflate } = require('zlib');
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// Get ERR_BUFFER_TOO_LARGE by monkey-patching .end() to pretend more than
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// kMaxLength bytes have been read.
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assert(
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!hasOwnProperty.call(Deflate.prototype, 'end'),
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'Deflate.prototype does not define end',
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);
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Deflate.prototype.end = function() {
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this.nread = kMaxLength + 1;
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// Hit check in zlibBufferOnData for node >= 14.6.0 (ec804f231f)
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this.emit('data', Buffer.alloc(0));
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// Hit check in zlibBufferOnEnd for node < 14.6.0 (ec804f231f)
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this.close = () => {};
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this.emit('end');
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};
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try {
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deflate(Buffer.alloc(0), (err) => {
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assert.strictEqual(err && err.code, 'ERR_BUFFER_TOO_LARGE');
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exports.ERR_BUFFER_TOO_LARGE = err.constructor;
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});
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} finally {
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delete Deflate.prototype.end;
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function makeNodeErrorWithCode(Base, key) {
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return function NodeError(...args) {
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let error;
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if (excludedStackFn === undefined) {
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error = new Base();
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} else {
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const limit = Error.stackTraceLimit;
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Error.stackTraceLimit = 0;
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error = new Base();
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// Reset the limit and setting the name property.
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Error.stackTraceLimit = limit;
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}
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const message = getMessage(key, args, error);
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ObjectDefineProperty(error, 'message', {
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value: message,
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enumerable: false,
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writable: true,
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configurable: true,
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});
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ObjectDefineProperty(error, 'toString', {
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value() {
77+
return `${this.name} [${key}]: ${this.message}`;
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},
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enumerable: false,
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writable: true,
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configurable: true,
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});
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addCodeToName(error, Base.name, key);
84+
error.code = key;
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return error;
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};
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}
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function addCodeToName(err, name, code) {
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// Set the stack
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if (excludedStackFn !== undefined) {
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Error.captureStackTrace(err, excludedStackFn);
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}
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// Add the error code to the name to include it in the stack trace.
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err.name = `${name} [${code}]`;
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// Access the stack to generate the error message including the error code
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// from the name.
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// eslint-disable-next-line no-unused-expressions
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err.stack;
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// Reset the name to the actual name.
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if (name === 'SystemError') {
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ObjectDefineProperty(err, 'name', {
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value: name,
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enumerable: false,
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writable: true,
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configurable: true
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});
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} else {
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delete err.name;
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}
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}
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// Utility function for registering the error codes. Only used here. Exported
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// *only* to allow for testing.
115+
function E(sym, val, def) {
116+
messages.set(sym, val);
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def = makeNodeErrorWithCode(def, sym);
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codes[sym] = def;
39119
}
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assert(
41-
exports.ERR_BUFFER_TOO_LARGE,
42-
'zlib.deflate calls callback immediately on error',
43-
);
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45-
// Get ERR_INVALID_ARG_TYPE by calling Buffer.alloc with an invalid type
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try {
47-
Buffer.alloc(true);
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} catch (err) {
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assert.strictEqual(err.code, 'ERR_INVALID_ARG_TYPE');
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exports.ERR_INVALID_ARG_TYPE = err.constructor;
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121+
function getMessage(key, args, self) {
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const msg = messages.get(key);
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if (typeof msg === 'function') {
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assert(
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msg.length <= args.length, // Default options do not count.
127+
`Code: ${key}; The provided arguments length (${args.length}) does not ` +
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`match the required ones (${msg.length}).`
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);
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return msg.apply(self, args);
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}
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const expectedLength = (msg.match(/%[dfijoOs]/g) || []).length;
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assert(
135+
expectedLength === args.length,
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`Code: ${key}; The provided arguments length (${args.length}) does not ` +
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`match the required ones (${expectedLength}).`
138+
);
139+
if (args.length === 0)
140+
return msg;
141+
142+
args.unshift(msg);
143+
return lazyInternalUtilInspect().format.apply(null, args);
51144
}
52-
assert(
53-
exports.ERR_INVALID_ARG_TYPE,
54-
'Buffer.alloc throws for Boolean argument',
55-
);
56-
57-
// Get ERR_STREAM_PREMATURE_CLOSE using stream.finish
58-
const readable = new Readable();
59-
finished(readable, (err) => {
60-
assert.strictEqual(err && err.code, 'ERR_STREAM_PREMATURE_CLOSE');
61-
exports.ERR_STREAM_PREMATURE_CLOSE = err.constructor;
62-
});
63-
readable.emit('close');
64-
assert(
65-
exports.ERR_STREAM_PREMATURE_CLOSE,
66-
'stream.finished calls callback on close',
67-
);
68-
69-
// eslint-disable-next-line unicorn/custom-error-definition
70-
exports.ERR_SYNC_NOT_SUPPORTED = class InflateAutoError extends Error {
145+
146+
E('ERR_BUFFER_TOO_LARGE',
147+
'Cannot create a Buffer larger than %s bytes',
148+
RangeError);
149+
E('ERR_INVALID_ARG_TYPE',
150+
(name, expected, actual) => {
151+
assert(typeof name === 'string', "'name' must be a string");
152+
if (!ArrayIsArray(expected)) {
153+
expected = [expected];
154+
}
155+
156+
let msg = 'The ';
157+
if (name.endsWith(' argument')) {
158+
// For cases like 'first argument'
159+
msg += `${name} `;
160+
} else {
161+
const type = name.includes('.') ? 'property' : 'argument';
162+
msg += `"${name}" ${type} `;
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}
164+
msg += 'must be ';
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166+
const types = [];
167+
const instances = [];
168+
const other = [];
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170+
for (const value of expected) {
171+
assert(typeof value === 'string',
172+
'All expected entries have to be of type string');
173+
if (kTypes.includes(value)) {
174+
types.push(value.toLowerCase());
175+
} else if (classRegExp.test(value)) {
176+
instances.push(value);
177+
} else {
178+
assert(value !== 'object',
179+
'The value "object" should be written as "Object"');
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other.push(value);
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}
182+
}
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184+
// Special handle `object` in case other instances are allowed to outline
185+
// the differences between each other.
186+
if (instances.length > 0) {
187+
const pos = types.indexOf('object');
188+
if (pos !== -1) {
189+
types.splice(pos, 1);
190+
instances.push('Object');
191+
}
192+
}
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if (types.length > 0) {
195+
if (types.length > 2) {
196+
const last = types.pop();
197+
msg += `one of type ${types.join(', ')}, or ${last}`;
198+
} else if (types.length === 2) {
199+
msg += `one of type ${types[0]} or ${types[1]}`;
200+
} else {
201+
msg += `of type ${types[0]}`;
202+
}
203+
if (instances.length > 0 || other.length > 0)
204+
msg += ' or ';
205+
}
206+
207+
if (instances.length > 0) {
208+
if (instances.length > 2) {
209+
const last = instances.pop();
210+
msg += `an instance of ${instances.join(', ')}, or ${last}`;
211+
} else {
212+
msg += `an instance of ${instances[0]}`;
213+
if (instances.length === 2) {
214+
msg += ` or ${instances[1]}`;
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}
216+
}
217+
if (other.length > 0)
218+
msg += ' or ';
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}
220+
221+
if (other.length > 0) {
222+
if (other.length > 2) {
223+
const last = other.pop();
224+
msg += `one of ${other.join(', ')}, or ${last}`;
225+
} else if (other.length === 2) {
226+
msg += `one of ${other[0]} or ${other[1]}`;
227+
} else {
228+
if (other[0].toLowerCase() !== other[0])
229+
msg += 'an ';
230+
msg += `${other[0]}`;
231+
}
232+
}
233+
234+
if (actual == null) {
235+
msg += `. Received ${actual}`;
236+
} else if (typeof actual === 'function' && actual.name) {
237+
msg += `. Received function ${actual.name}`;
238+
} else if (typeof actual === 'object') {
239+
if (actual.constructor && actual.constructor.name) {
240+
msg += `. Received an instance of ${actual.constructor.name}`;
241+
} else {
242+
const inspected = lazyInternalUtilInspect()
243+
.inspect(actual, { depth: -1 });
244+
msg += `. Received ${inspected}`;
245+
}
246+
} else {
247+
let inspected = lazyInternalUtilInspect()
248+
.inspect(actual, { colors: false });
249+
if (inspected.length > 25)
250+
inspected = `${inspected.slice(0, 25)}...`;
251+
msg += `. Received type ${typeof actual} (${inspected})`;
252+
}
253+
return msg;
254+
}, TypeError);
255+
E('ERR_STREAM_PREMATURE_CLOSE', 'Premature close', Error);
256+
257+
codes.ERR_SYNC_NOT_SUPPORTED = class InflateAutoError extends Error {
71258
constructor(target) {
72259
super();
73260
let message = 'Synchronous operation is not supported';

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