Ruby Emoji Regex 💎

A set of Ruby regular expressions for matching Unicode Emoji symbols.

Background

This is based upon the fantastic work from Mathias Bynens' emoji-regex Javascript package. emoji-regex is cleverly assembled based upon data from the Unicode Consortium.

The regular expressions provided herein are derived from that pacakge.

Installation

gem install emoji_regex

Usage

emoji_regex provides three regular expressions:

EmojiRegex::RGIEmoji is the regex you most likely want. It matches all emoji recommended for general interchange, as defined by the Unicode standard's RGI_Emoji property.
EmojiRegex::Regex is deprecated, and will be replaced by RGIEmoji in a future major version. It matches emoji which present as emoji by default, and those which present as emoji when combined with U+FE0F VARIATION SELECTOR-16.
EmojiRegex::Text matches emoji which present as text by default (regardless of variation selector), as well as those which present as emoji by default.

RGI vs Emoji vs Text Presentation

RGI_Emoji is a property of emoji symbols, defined in Unicode Technical Report #51 which marks emoji as being supported by major vendors and therefore expected to be usable generally. In most cases, this is the property you will want when seeking emoji characters.

Emoji_Presentation is another such property, defined in UTR#51 which controls whether symbols are intended to be rendered as emoji by default.

Generally, for emoji which re-use Unicode code points which existed before Emoji itself was introduced to Unicode, Emoji_Presentation is false. Emoji_Presentation may be true but RGI_Emoji false for characters with non-standard emoji-like representations in certain conditions. Notable cases are the Emoji Keycap Sequences (#️⃣, 1️⃣, 9️⃣, *️⃣, etc.) which are sequences composed of three characters; the base character, an U+FE0F VARIATION SELECTOR-16, and finally the U+20E3 COMBINING ENCLOSING KEYCAP.

These characters, therefore, are matched to varying degrees of precision by each of the regular expressions included in this package;

# is matched only by EmojiRegex::Text as it is considered to be a text part of a possible emoji.
#️ is matched by EmojiRegex::Regex as well as EmojiRegex::Text as it has Emoji_Presentation despite not being a generally accepted Emoji or recommended for general interchange.
#️⃣ is matched by all three regular expressions, as it is recommended for general interchange.

It's most likely that the regular expression you want is EmojiRegex::RGIEmoji! ☺️

Example

require 'emoji_regex'

text = <<TEXT
\u{231A}: ⌚ default Emoji presentation character (Emoji_Presentation)
\u{2194}: ↔ default text presentation character
\u{2194}\u{FE0F}: ↔️ default text presentation character with Emoji variation selector
#: # default text presentation character
#\u{FE0F}: #️ default text presentation character with Emoji variation selector
#\u{FE0F}\u{20E3}: #️⃣ default text presentation character with Emoji variation selector and combining enclosing keycap
\u{1F469}: 👩 Emoji modifier base (Emoji_Modifier_Base)
\u{1F469}\u{1F3FF}: 👩🏿 Emoji modifier base followed by a modifier
TEXT

puts 'EmojiRegex::RGIEmoji'
text.scan EmojiRegex::RGIEmoji do |emoji|
  puts "Matched sequence #{emoji} — code points: #{emoji.length}"
end

puts ''

puts 'EmojiRegex::Regex'
text.scan EmojiRegex::Regex do |emoji|
  puts "Matched sequence #{emoji} — code points: #{emoji.length}"
end

puts ''

puts 'EmojiRegex::Text'
text.scan EmojiRegex::Text do |emoji|
  puts "Matched sequence #{emoji} — code points: #{emoji.length}"
end

Console output:

EmojiRegex::RGIEmoji
Matched sequence ⌚ — code points: 1
Matched sequence ⌚ — code points: 1
Matched sequence ↔️ — code points: 2
Matched sequence ↔️ — code points: 2
Matched sequence #️⃣ — code points: 3
Matched sequence #️⃣ — code points: 3
Matched sequence 👩 — code points: 1
Matched sequence 👩 — code points: 1
Matched sequence 👩🏿 — code points: 2
Matched sequence 👩🏿 — code points: 2

EmojiRegex::Regex
Matched sequence ⌚ — code points: 1
Matched sequence ⌚ — code points: 1
Matched sequence ↔️ — code points: 2
Matched sequence ↔️ — code points: 2
Matched sequence #️ — code points: 2
Matched sequence #️ — code points: 2
Matched sequence #️⃣ — code points: 3
Matched sequence #️⃣ — code points: 3
Matched sequence 👩 — code points: 1
Matched sequence 👩 — code points: 1
Matched sequence 👩🏿 — code points: 2
Matched sequence 👩🏿 — code points: 2

EmojiRegex::Text
Matched sequence ⌚ — code points: 1
Matched sequence ⌚ — code points: 1
Matched sequence ↔ — code points: 1
Matched sequence ↔ — code points: 1
Matched sequence ↔️ — code points: 2
Matched sequence ↔️ — code points: 2
Matched sequence # — code points: 1
Matched sequence # — code points: 1
Matched sequence #️ — code points: 2
Matched sequence #️ — code points: 2
Matched sequence #️⃣ — code points: 3
Matched sequence #️⃣ — code points: 3
Matched sequence 👩 — code points: 1
Matched sequence 👩 — code points: 1
Matched sequence 👩🏿 — code points: 2
Matched sequence 👩🏿 — code points: 2

Note: The above code and output are verified as part of the spec suite.

Development

Requirements

Ruby
Node (v6 or newer)
Yarn

Initial setup

To install all the Ruby and Javascript dependencies, you can run:

bin/setup

To update the Ruby source files based on the emoji-regex library:

bundle exec rake regenerate

Specs

A spec suite is provided, which can be run as:

bundle exec rake spec

Versioning Policy

Since Version 1.0.0, Ruby Emoji Regex's versions have followed that of the emoji-regex package, minus 6 major versions.

Each published version of Ruby Emoji Regex will aim to:

Include any changes in the provided regex in a version matching that of the emoji-regex package, keeping the major and minor versions in step.
When a patch revision of emoji-regex is released, if its changes affect the Ruby port meaningfully, a version will be released with the same or greater patch version.
If a change is required to correct a bug specific to the Ruby port, the patch number will be incremented.

Likewise, and so far coincidentally, versions of Ruby Emoji Regex follow the Unicode Standard's version, minus 10 major versions. Therefore, version 1 included Unicode 11, version 2 Unicode 12, and 3 Unicode 13.

Ruby Compatibility Policy

While Ruby Emoji Regex uses features which should function on any Ruby version, it is explicitly intended to work on MRI Ruby versions which are currently within normal maintenance according to the Ruby team.

Creating a release

Update the version in emoji_regex.gemspec
rake release