wrap-ansi

What is wrap-ansi?

The wrap-ansi npm package is used to wrap words to a specified column width without breaking ANSI escape codes. This is particularly useful for formatting command-line output that includes color or other special styles.

What are wrap-ansi's main functionalities?

Word wrapping

This feature allows you to wrap a string to a specified width. In the code sample, the input string is wrapped so that each line does not exceed 20 characters.

const wrapAnsi = require('wrap-ansi');
const input = 'The quick brown fox jumps over the lazy dog';
const output = wrapAnsi(input, 20);
console.log(output);

Respecting ANSI escape codes

This feature ensures that ANSI escape codes are not broken when the text is wrapped. The code sample demonstrates wrapping text that includes ANSI escape codes for red text.

const wrapAnsi = require('wrap-ansi');
const input = '\u001B[31mThe quick brown fox\u001B[39m jumps over the lazy dog';
const output = wrapAnsi(input, 20);
console.log(output);

Hard wrapping

This feature allows for hard wrapping, which ensures that line breaks are inserted at exactly the specified column, even if it means breaking a word. The code sample shows how to use the 'hard' option to enforce strict column width.

const wrapAnsi = require('wrap-ansi');
const input = 'The quick brown \nfox jumps over the lazy dog';
const output = wrapAnsi(input, 20, { hard: true });
console.log(output);

Other packages similar to wrap-ansi

cli-truncate

The cli-truncate package is similar to wrap-ansi in that it also deals with ANSI escape codes and string truncation in the terminal. However, cli-truncate focuses on truncating strings to a specified width without breaking the escape codes, rather than wrapping text to a new line.

slice-ansi

Slice-ansi is another package that handles strings containing ANSI escape codes. It allows you to slice a string with ANSI escape codes, similar to how Array.prototype.slice works. Unlike wrap-ansi, it does not wrap text but rather extracts a substring without breaking the escape codes.

string-width

String-width is a package that can calculate the visual width of a string in the terminal, taking into account ANSI escape codes and double-width characters. It does not wrap or modify the string itself but can be used in conjunction with wrap-ansi to determine where to wrap a string.

README

wrap-ansi

Wordwrap a string with ANSI escape codes

Install

npm install wrap-ansi

Usage

import chalk from 'chalk';
import wrapAnsi from 'wrap-ansi';

const input = 'The quick brown ' + chalk.red('fox jumped over ') +
	'the lazy ' + chalk.green('dog and then ran away with the unicorn.');

console.log(wrapAnsi(input, 20));

API

wrapAnsi(string, columns, options?)

Wrap words to the specified column width.

string

Type: string

A string with ANSI escape codes, like one styled by chalk.

Newline characters will be normalized to \n.

columns

Type: number

The number of columns to wrap the text to.

options

Type: object

hard

Type: boolean
Default: false

By default the wrap is soft, meaning long words may extend past the column width. Setting this to true will make it hard wrap at the column width.

wordWrap

Type: boolean
Default: true

By default, an attempt is made to split words at spaces, ensuring that they don't extend past the configured columns. If wordWrap is false, each column will instead be completely filled splitting words as necessary.

trim

Type: boolean
Default: true

Whitespace on all lines is removed by default. Set this option to false if you don't want to trim.

Related

• slice-ansi - Slice a string with ANSI escape codes
• cli-truncate - Truncate a string to a specific width in the terminal
• chalk - Terminal string styling done right
• jsesc - Generate ASCII-only output from Unicode strings. Useful for creating test fixtures.