ansi-escapes

What is ansi-escapes?

The ansi-escapes npm package provides a collection of ANSI escape codes for manipulating the terminal. These codes can be used to control cursor movement, erase text, manage scrollback, and more, allowing developers to create interactive command-line applications.

What are ansi-escapes's main functionalities?

Cursor Movement

Moves the cursor to the specified x and y position (column 5, row 10).

const ansiEscapes = require('ansi-escapes');
console.log(ansiEscapes.cursorTo(5, 10));

Erase Lines

Erases the specified number of lines (2 lines in this case) from the current cursor position up.

const ansiEscapes = require('ansi-escapes');
console.log(ansiEscapes.eraseLines(2));

Scrolling

Scrolls the terminal viewport up or down one line.

const ansiEscapes = require('ansi-escapes');
console.log(ansiEscapes.scrollUp());
console.log(ansiEscapes.scrollDown());

Clearing Screen

Clears the terminal screen and moves the cursor to the upper-left corner.

const ansiEscapes = require('ansi-escapes');
console.log(ansiEscapes.clearScreen);

Beep

Triggers the terminal bell, which often makes an audible beep sound.

const ansiEscapes = require('ansi-escapes');
console.log(ansiEscapes.beep);

Other packages similar to ansi-escapes

chalk

Chalk is a popular package for styling terminal strings with colors and styles but does not include the cursor and screen manipulation features of ansi-escapes.

blessed

Blessed is a high-level terminal interface library that includes screen and cursor manipulation, similar to ansi-escapes, but offers a more comprehensive API for building terminal applications.

cli-cursor

Cli-cursor allows for showing and hiding the terminal cursor, which is a subset of the functionality provided by ansi-escapes.

inquirer

Inquirer is a package for creating interactive command-line user interfaces. It uses escape codes under the hood for cursor movement and screen manipulation, similar to ansi-escapes, but provides a higher-level API for building prompts.

README

ansi-escapes

ANSI escape codes for manipulating the terminal

Install

npm install ansi-escapes

Usage

import ansiEscapes from 'ansi-escapes';

// Moves the cursor two rows up and to the left
process.stdout.write(ansiEscapes.cursorUp(2) + ansiEscapes.cursorLeft);
//=> '\u001B[2A\u001B[1000D'

You can also use it in the browser with Xterm.js:

import ansiEscapes from 'ansi-escapes';
import {Terminal} from 'xterm';
import 'xterm/css/xterm.css';

const terminal = new Terminal({…});

// Moves the cursor two rows up and to the left
terminal.write(ansiEscapes.cursorUp(2) + ansiEscapes.cursorLeft);
//=> '\u001B[2A\u001B[1000D'

API

cursorTo(x, y?)

Set the absolute position of the cursor. x0 y0 is the top left of the screen.

cursorMove(x, y?)

Set the position of the cursor relative to its current position.

cursorUp(count)

Move cursor up a specific amount of rows. Default is 1.

cursorDown(count)

Move cursor down a specific amount of rows. Default is 1.

cursorForward(count)

Move cursor forward a specific amount of columns. Default is 1.

cursorBackward(count)

Move cursor backward a specific amount of columns. Default is 1.

cursorLeft

Move cursor to the left side.

cursorSavePosition

Save cursor position.

cursorRestorePosition

Restore saved cursor position.

cursorGetPosition

Get cursor position.

cursorNextLine

Move cursor to the next line.

cursorPrevLine

Move cursor to the previous line.

cursorHide

Hide cursor.

cursorShow

Show cursor.

eraseLines(count)

Erase from the current cursor position up the specified amount of rows.

eraseEndLine

Erase from the current cursor position to the end of the current line.

eraseStartLine

Erase from the current cursor position to the start of the current line.

eraseLine

Erase the entire current line.

eraseDown

Erase the screen from the current line down to the bottom of the screen.

eraseUp

Erase the screen from the current line up to the top of the screen.

eraseScreen

Erase the screen and move the cursor the top left position.

scrollUp

Scroll display up one line.

scrollDown

Scroll display down one line.

clearScreen

Clear the terminal screen. (Viewport)

clearTerminal

Clear the whole terminal, including scrollback buffer. (Not just the visible part of it)

enterAlternativeScreen

Enter the alternative screen.

exitAlternativeScreen

Exit the alternative screen, assuming enterAlternativeScreen was called before.

beep

Output a beeping sound.

link(text, url)

Create a clickable link.

Supported terminals. Use supports-hyperlinks to detect link support.

image(filePath, options?)

Display an image.

Currently only supported on iTerm2 >=3

See term-img for a higher-level module.

input

Type: Buffer

Buffer of an image. Usually read in with fs.readFile().

options

Type: object

width

height

Type: string | number

The width and height are given as a number followed by a unit, or the word "auto".

• N: N character cells.
• Npx: N pixels.
• N%: N percent of the session's width or height.
• auto: The image's inherent size will be used to determine an appropriate dimension.

preserveAspectRatio

Type: boolean
Default: true

iTerm.setCwd(path?)

Type: string
Default: process.cwd()

Inform iTerm2 of the current directory to help semantic history and enable Cmd-clicking relative paths.

iTerm.annotation(message, options?)

Creates an escape code to display an "annotation" in iTerm2.

An annotation looks like this when shown:

See the iTerm Proprietary Escape Codes documentation for more information.

message

Type: string

The message to display within the annotation.

The | character is disallowed and will be stripped.

options

Type: object

length

Type: number
Default: The remainder of the line

Nonzero number of columns to annotate.

x

Type: number
Default: Cursor position

Starting X coordinate.

Must be used with y and length.

y

Type: number
Default: Cursor position

Starting Y coordinate.

Must be used with x and length.

isHidden

Type: boolean
Default: false

Create a "hidden" annotation.

Annotations created this way can be shown using the "Show Annotations" iTerm command.

Related

• ansi-styles - ANSI escape codes for styling strings in the terminal