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// 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 util = require('util');
function Console(stdout, stderr, ignoreErrors = true) {
if (!(this instanceof Console)) {
return new Console(stdout, stderr, ignoreErrors);
}
if (!stdout || typeof stdout.write !== 'function') {
throw new TypeError('Console expects a writable stream instance');
}
if (!stderr) {
stderr = stdout;
} else if (typeof stderr.write !== 'function') {
throw new TypeError('Console expects writable stream instances');
}
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);
// 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) {
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) {
// 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,
`${util.format.apply(null, args)}\n`,
this._stdoutErrorHandler);
};
Console.prototype.info = Console.prototype.log;
Console.prototype.warn = function warn(...args) {
write(this._ignoreErrors,
this._stderr,
`${util.format.apply(null, args)}\n`,
this._stderrErrorHandler);
};
Console.prototype.error = Console.prototype.warn;
Console.prototype.dir = function dir(object, options) {
options = Object.assign({customInspect: false}, options);
write(this._ignoreErrors,
this._stdout,
`${util.inspect(object, options)}\n`,
this._stdoutErrorHandler);
};
Console.prototype.time = function time(label) {
this._times.set(label, process.hrtime());
};
Console.prototype.timeEnd = function timeEnd(label) {
const time = this._times.get(label);
if (!time) {
process.emitWarning(`No such label '${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) {
// TODO probably can to do this better with V8's debug object once that is
// exposed.
var err = new Error();
err.name = 'Trace';
err.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));
}
};
module.exports = new Console(process.stdout, process.stderr);
module.exports.Console = Console;
function noop() {}
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