symfony-style-console/modern/Output/StreamOutput.js

Use the style and utilities of the Symfony Console in Node.js

import Output from './Output';
import { VERBOSITY_NORMAL } from './OutputInterface';
import { EOL, DIRECTORY_SEPARATOR } from '../env';
/**
 * StreamOutput writes the output to a given stream.
 *
 * Usage:
 *
 * ```
 * const output = new StreamOutput(process.stdout)
 * ```
 *
 * As `StreamOutput` can use any stream, you can also use a file:
 *
 * ```
 * const output = new StreamOutput(fs.createWriteStream('/path/to/output.log', { flags: 'a' }))
 * ```
 *
 * @author Fabien Potencier <fabien@symfony.com>
 *
 * Original PHP class
 *
 * @author Florian Reuschel
 *
 * Port to TypeScript
 */
export default class StreamOutput extends Output {
    /**
     * Creates a new StreamOutput instance
     *
     * @param stream    A stream resource
     * @param verbosity The verbosity level (one of the VERBOSITY constants in OutputInterface)
     * @param decorated Whether to decorate messages (null for auto-guessing)
     * @param formatter Output formatter instance (null to use default OutputFormatter)
     *
     * @throws InvalidArgumentException When first argument is not a real stream
     */
    constructor(stream, verbosity = VERBOSITY_NORMAL, decorated = null, formatter = null) {
        super(verbosity, decorated, formatter);
        this.stream = stream;
        if (null === decorated) {
            decorated = this.hasColorSupport();
        }
    }
    /**
     * Gets the stream attached to this StreamOutput instance.
     *
     * @return A stream resource
     */
    getStream() {
        return this.stream;
    }
    /**
     * {@inheritdoc}
     */
    doWrite(message, newline) {
        if (false === this.stream.write(message) ||
            (newline && false === this.stream.write(EOL))) {
            // should never happen
            throw new Error('Unable to write output.');
        }
    }
    /**
     * Returns true if the stream supports colorization.
     *
     * Colorization is disabled if not supported by the stream:
     *
     *  -  Windows != 10.0.10586 without Ansicon, ConEmu or Mintty
     *  -  non tty consoles
     *
     * @return bool true if the stream supports colorization, false otherwise
     */
    hasColorSupport() {
        if (DIRECTORY_SEPARATOR === '\\') {
            const os = require('os');
            return ('10.0.10586' === os.release() ||
                process.env.ANSICON ||
                'ON' === process.env.ConEmuANSI ||
                'xterm' === process.env.TERM);
        }
        if (typeof this.stream.fd !== 'undefined') {
            return require('tty').isatty(this.stream.fd);
        }
        else {
            return false;
        }
    }
}