// Copyright Joyent, Inc. and other Node contributors. // // Permission is hereby granted, free of charge, to any person obtaining a // copy of this software and associated documentation files (the // "Software"), to deal in the Software without restriction, including // without limitation the rights to use, copy, modify, merge, publish, // distribute, sublicense, and/or sell copies of the Software, and to permit // persons to whom the Software is furnished to do so, subject to the // following conditions: // // The above copyright notice and this permission notice shall be included // in all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE // USE OR OTHER DEALINGS IN THE SOFTWARE. 'use strict'; const errors = require('internal/errors'); const util = require('util'); const kCounts = Symbol('counts'); // Track amount of indentation required via `console.group()`. const kGroupIndent = Symbol('groupIndent'); function Console(stdout, stderr, ignoreErrors = true) { if (!(this instanceof Console)) { return new Console(stdout, stderr, ignoreErrors); } if (!stdout || typeof stdout.write !== 'function') { throw new errors.TypeError('ERR_CONSOLE_WRITABLE_STREAM', 'stdout'); } if (!stderr) { stderr = stdout; } else if (typeof stderr.write !== 'function') { throw new errors.TypeError('ERR_CONSOLE_WRITABLE_STREAM', 'stderr'); } var prop = { writable: true, enumerable: false, configurable: true }; prop.value = stdout; Object.defineProperty(this, '_stdout', prop); prop.value = stderr; Object.defineProperty(this, '_stderr', prop); prop.value = ignoreErrors; Object.defineProperty(this, '_ignoreErrors', prop); prop.value = new Map(); Object.defineProperty(this, '_times', prop); prop.value = createWriteErrorHandler(stdout); Object.defineProperty(this, '_stdoutErrorHandler', prop); prop.value = createWriteErrorHandler(stderr); Object.defineProperty(this, '_stderrErrorHandler', prop); this[kCounts] = new Map(); Object.defineProperty(this, kGroupIndent, { writable: true }); this[kGroupIndent] = ''; // bind the prototype functions to this Console instance var keys = Object.keys(Console.prototype); for (var v = 0; v < keys.length; v++) { var k = keys[v]; this[k] = this[k].bind(this); } } // Make a function that can serve as the callback passed to `stream.write()`. function createWriteErrorHandler(stream) { return (err) => { // This conditional evaluates to true if and only if there was an error // that was not already emitted (which happens when the _write callback // is invoked asynchronously). if (err && !stream._writableState.errorEmitted) { // If there was an error, it will be emitted on `stream` as // an `error` event. Adding a `once` listener will keep that error // from becoming an uncaught exception, but since the handler is // removed after the event, non-console.* writes won’t be affected. stream.once('error', noop); } }; } function write(ignoreErrors, stream, string, errorhandler, groupIndent) { if (groupIndent.length !== 0) { if (string.indexOf('\n') !== -1) { string = string.replace(/\n/g, `\n${groupIndent}`); } string = groupIndent + string; } string += '\n'; if (!ignoreErrors) return stream.write(string); // There may be an error occurring synchronously (e.g. for files or TTYs // on POSIX systems) or asynchronously (e.g. pipes on POSIX systems), so // handle both situations. try { // Add and later remove a noop error handler to catch synchronous errors. stream.once('error', noop); stream.write(string, errorhandler); } catch (e) { // console is a debugging utility, so it swallowing errors is not desirable // even in edge cases such as low stack space. if (e.message === 'Maximum call stack size exceeded') throw e; // Sorry, there’s no proper way to pass along the error here. } finally { stream.removeListener('error', noop); } } // As of v8 5.0.71.32, the combination of rest param, template string // and .apply(null, args) benchmarks consistently faster than using // the spread operator when calling util.format. Console.prototype.log = function log(...args) { write(this._ignoreErrors, this._stdout, util.format.apply(null, args), this._stdoutErrorHandler, this[kGroupIndent]); }; Console.prototype.info = Console.prototype.log; Console.prototype.warn = function warn(...args) { write(this._ignoreErrors, this._stderr, util.format.apply(null, args), this._stderrErrorHandler, this[kGroupIndent]); }; Console.prototype.error = Console.prototype.warn; Console.prototype.dir = function dir(object, options) { options = Object.assign({ customInspect: false }, options); write(this._ignoreErrors, this._stdout, util.inspect(object, options), this._stdoutErrorHandler, this[kGroupIndent]); }; Console.prototype.time = function time(label = 'default') { // Coerces everything other than Symbol to a string label = `${label}`; this._times.set(label, process.hrtime()); }; Console.prototype.timeEnd = function timeEnd(label = 'default') { // Coerces everything other than Symbol to a string label = `${label}`; const time = this._times.get(label); if (!time) { process.emitWarning(`No such label '${label}' for console.timeEnd()`); return; } const duration = process.hrtime(time); const ms = duration[0] * 1000 + duration[1] / 1e6; this.log('%s: %sms', label, ms.toFixed(3)); this._times.delete(label); }; Console.prototype.trace = function trace(...args) { const err = { name: 'Trace', message: util.format.apply(null, args) }; Error.captureStackTrace(err, trace); this.error(err.stack); }; Console.prototype.assert = function assert(expression, ...args) { if (!expression) { require('assert').ok(false, util.format.apply(null, args)); } }; // Defined by: https://console.spec.whatwg.org/#clear Console.prototype.clear = function clear() { // It only makes sense to clear if _stdout is a TTY. // Otherwise, do nothing. if (this._stdout.isTTY) { // The require is here intentionally to avoid readline being // required too early when console is first loaded. const { cursorTo, clearScreenDown } = require('readline'); cursorTo(this._stdout, 0, 0); clearScreenDown(this._stdout); } }; // Defined by: https://console.spec.whatwg.org/#count Console.prototype.count = function count(label = 'default') { // Ensures that label is a string, and only things that can be // coerced to strings. e.g. Symbol is not allowed label = `${label}`; const counts = this[kCounts]; let count = counts.get(label); if (count === undefined) count = 1; else count++; counts.set(label, count); this.log(`${label}: ${count}`); }; // Not yet defined by the https://console.spec.whatwg.org, but // proposed to be added and currently implemented by Edge. Having // the ability to reset counters is important to help prevent // the counter from being a memory leak. Console.prototype.countReset = function countReset(label = 'default') { const counts = this[kCounts]; counts.delete(`${label}`); }; Console.prototype.group = function group(...data) { if (data.length > 0) { this.log(...data); } this[kGroupIndent] += ' '; }; Console.prototype.groupCollapsed = Console.prototype.group; Console.prototype.groupEnd = function groupEnd() { this[kGroupIndent] = this[kGroupIndent].slice(0, this[kGroupIndent].length - 2); }; module.exports = new Console(process.stdout, process.stderr); module.exports.Console = Console; function noop() {}