_{Inspired by pseudo-localization at Netflix and Firefox}

pseudo-localization

English	Pseudo Language

---

pseudo-localization is a script that performs pseudolocalization against the DOM.

Demo here. Changing text nodes and adding or removing trees of elements will trigger a pseudolocalization run on all the new text added to the DOM. Try it using the devtools.

Installation

Through npm

npm install pseudo-localization

Raw script (without npm)

Copy paste the script in it's entirty from here and use as you wish.

Usage

import or require the npm module

pseudo-localization is just a script and can be invoked like so:

const pseudoLocalization = require('pseudo-localization'); 

pseudoLocalization.start();

// Later, if needed
pseudoLocalization.stop();

To use pseudo-localization in React, Vue, Ember or anything else, hook the start and stop methods into your libraries component lifecycles. In React for example:

import React from 'react';
import pseudoLocalization from 'pseudo-localization';

class PseudoLocalization extends React.Component {
  componentDidMount() {
    pseudoLocalization.start();
  }
  componentWillUnmount() {
    pseudoLocalization.stop();
  }
}

// And use it

class Page extends React.Component {
  render() {
    return (
      <main>
       <PseudoLocalization />
       <h1>I will get pseudo localized along with everything else under document.body!</h1>
      <main>
    );
  }
}

You can also call the underlying localize function to pseudo-localize any string.

import { localize } from 'pseudo-localization';
// OR
import localize from 'pseudo-localization/localize';

console.log(localize('hello')); // --> ħḗḗŀŀǿǿ
console.log(localize('hello', { strategy: 'bidi' })); // --> oʅʅǝɥ

A good use-case for localize is testing that strings are actually being localized and not hard coded.

import { localize } from 'pseudo-localization';
import translate from './my-translation-lib';

// Pseudo localize every string returned from your normal translation function.
const _ = key => localize(translate(key, navigator.language));

_('Some Localized Text'); // Şǿǿḿḗḗ Ŀǿǿƈȧȧŀīẑḗḗḓ Ŧḗḗẋŧ
// Or, in React for example
const Header = () => <h1>{_('Localized Header Text')}</h1>;

Any strings that do not pass through the translation function will now stand out in the UI because the will not be pseudo-localized.

Strategies

pseudo-localization supports two strategies:

1. accented
2. bidi

accented - Ȧȧƈƈḗḗƞŧḗḗḓ Ḗḗƞɠŀīīşħ

Usage: pseudoLocalization.start({ strategy: 'accented' }); or simply pseudoLocalization.start();.

In Accented English all Latin letters are replaced by accented Unicode counterparts which don't impair the readability of the content. This allows developers to quickly test if any given string is being correctly displayed in its 'translated' form. Additionally, simple heuristics are used to make certain words longer to better simulate the experience of international users.

bidi - ɥsıʅƃuƎ ıpıԐ

Usage: pseudoLocalization.start({ strategy: 'bidi' });.

Bidi English is a fake RTL locale. All words are surrounded by Unicode formatting marks forcing the RTL directionality of characters. In addition, to make the reversed text easier to read, individual letters are flipped.

Why?

To catch localization problems like:

• Translated text that is significantly longer than the source language, and does not fit within the UI constraints, or which causes text breaks at awkward positions.
• Font glyphs that are significantly larger than, or possess diacritic marks not found in, the source language, and which may be cut off vertically.
• Languages for which the reading order is not left-to-right, which is especially problematic for user input.
• Application code that assumes all characters fit into a limited character set, such as ASCII or ANSI, which can produce actual logic bugs if left uncaught.

In addition, the pseudo-localization process may uncover places where an element should be localizable, but is hard coded in a source language.

Docs

pseudo-localization exports three functions.

• pseudoLocalization.start(options)
• pseudoLocalization.stop()
• pseudoLocalization.localize(string, options)

pseudoLocalization.start(options)

Pseudo localizes the page and watched the DOM for additions/updates to continuously pseudo localize new content.

Accepts an options object as an argument. Here are the keys in the options object.

strategy - default ('accented')

The pseudo localization strategy to use when transforming strings. Accepted values are accented or bidi.

blacklistedNodeNames - default (['STYLE'])

An array of Node.nodeName strings that will be ignored when localizing. This is useful for skipping <style>, <text> svg nodes or other nodes that potentially doesn't make sense to apply pseudo localization to. <style> is skipped by default when blacklistedNodeNames is not provided.

pseudoLocalization.stop()

Stops watching the DOM for additions/updates to continuously pseudo localize new content.

pseudoLocalization.localize(string, options)

Accepts a string to apply pseudo localization to. Returns the pseudo localized version on the string. This function is used by pseudoLocalization.start internally.

Accepts an options object as an argument. Here are the keys in the options object.

strategy - default ('accented')

The pseudo localization strategy to use when transforming strings. Accepted values are accented or bidi.

blacklistedNodeNames - default (['STYLE'])

An array of Node.nodeName strings that will be ignored when localizing. This is useful for skipping <style>, <text> svg nodes or other nodes that potentially doesn't make sense to apply pseudo localization to. <style> is skipped by default when blacklistedNodeNames is not provided.

Support

Works in all evergreen browsers.