tap/node_modules/log-update/index.js

'use strict';
const ansiEscapes = require('ansi-escapes');
const cliCursor = require('cli-cursor');
const wrapAnsi = require('wrap-ansi');

const getWidth = stream => {
	const {columns} = stream;

	if (!columns) {
		return 80;
	}

	return columns;
};

const main = (stream, options) => {
	options = Object.assign({
		showCursor: false
	}, options);

	let previousLineCount = 0;
	let previousWidth = getWidth(stream);
	let previousOutput = '';

	const render = (...args) => {
		if (!options.showCursor) {
			cliCursor.hide();
		}

		let output = args.join(' ') + '\n';
		const width = getWidth(stream);
		if (output === previousOutput && previousWidth === width) {
			return;
		}

		previousOutput = output;
		previousWidth = width;
		output = wrapAnsi(output, width, {
			trim: false,
			hard: true,
			wordWrap: false
		});
		stream.write(ansiEscapes.eraseLines(previousLineCount) + output);
		previousLineCount = output.split('\n').length;
	};

	render.clear = () => {
		stream.write(ansiEscapes.eraseLines(previousLineCount));
		previousOutput = '';
		previousWidth = getWidth(stream);
		previousLineCount = 0;
	};

	render.done = () => {
		previousOutput = '';
		previousWidth = getWidth(stream);
		previousLineCount = 0;

		if (!options.showCursor) {
			cliCursor.show();
		}
	};

	return render;
};

module.exports = main(process.stdout);
// TODO: Remove this for the next major release
module.exports.default = module.exports;
module.exports.stderr = main(process.stderr);
module.exports.create = main;