discourse/spec/models/emoji_spec.rb
LY 9738c429c8
FIX: Correctly handle VS16 in toned ZWJ emoji sequences (#37419)
Previously, the emoji generation logic unconditionally inserted skin
tone modifiers at index 1. This caused issues for ZWJ sequences where
the base character is followed by a Variation Selector-16 (U+FE0F),
creating malformed sequences like `[Base] + [Tone] + [VS16] + [ZWJ]`.

This specifically broke emojis involving both skin tone and gender, such
as ":man_bouncing_ball:t2:" (⛹🏻‍♂️), causing them to fail to render as
images.

This commit updates the logic to strip the VS16 character at index 1
before inserting the skin tone, ensuring the generated sequence matches
standard RGI definitions.

Reference:
https://www.unicode.org/Public/17.0.0/emoji/emoji-zwj-sequences.txt

---

Part of this commit is generated by Gemini. I've tested the patch on my
local Discourse deployment.

P.S. Is it possible to use a more robust solution for handling Emojis?
IMHO, codepoint-level operations are tricky and may lead to issues (like
this one.)
2026-03-04 17:57:14 +11:00

197 lines
7.6 KiB
Ruby

# frozen_string_literal: true
RSpec.describe Emoji do
describe ".replacement_code" do
it "returns correct codepoints" do
expect(Emoji.replacement_code("1f47d").codepoints).to eq([128_125])
expect(Emoji.replacement_code("1f1e9-1f1ea").codepoints).to eq([127_465, 127_466])
end
end
describe ".load_custom" do
it "returns custom emoji without URL when upload_id is invalid" do
CustomEmoji.create!(name: "test", upload_id: 9999)
emoji = Emoji.load_custom.first
expect(emoji.name).to eq("test")
expect(emoji.url).to be_nil
end
end
describe ".unicode_replacements" do
before { Emoji.clear_cache }
it "generates correct keys for skin tone and gendered ZWJ sequences" do
replacements = Emoji.unicode_replacements
# Case 1: Man Bouncing Ball: Light Skin Tone (RGI)
# 26f9 (Base) + 1f3fb (Tone) + 200d (ZWJ) + 2642 (Gender) + fe0f (VS16)
man_bouncing_ball_rgi = [0x26f9, 0x1f3fb, 0x200d, 0x2642, 0xfe0f].pack("U*")
# Malformed sequence (Old Bug): VS16 incorrectly persisting in the middle
malformed_key = [0x26f9, 0x1f3fb, 0xfe0f, 0x200d, 0x2642, 0xfe0f].pack("U*")
expect(replacements.keys).to include(man_bouncing_ball_rgi)
expect(replacements.keys).not_to include(malformed_key)
expect(replacements[man_bouncing_ball_rgi]).to eq("man_bouncing_ball:t2")
# Case 2: Thumbs Up: Light Skin Tone
thumbs_up = [0x1f44d, 0x1f3fb].pack("U*")
expect(replacements.keys).to include(thumbs_up)
# Case 3: Family (Man, Woman, Girl)
family = [0x1f468, 0x200d, 0x1f469, 0x200d, 0x1f467].pack("U*")
expect(replacements.keys).to include(family)
end
end
describe ".lookup_unicode" do
before { Emoji.clear_cache }
it "returns correct unicode for skin tone and gendered ZWJ sequences" do
# Case 1: Man Bouncing Ball: Light Skin Tone (RGI)
expected_rgi = [0x26f9, 0x1f3fb, 0x200d, 0x2642, 0xfe0f].pack("U*")
expect(Emoji.lookup_unicode("man_bouncing_ball:t2")).to eq(expected_rgi)
# Case 2: Thumbs Up: Light Skin Tone
thumbs_up = [0x1f44d, 0x1f3fb].pack("U*")
expect(Emoji.lookup_unicode("+1:t2")).to eq(thumbs_up)
# Case 3: Family (Man, Woman, Girl)
family_skinned = [0x1f468, 0x200d, 0x1f469, 0x200d, 0x1f467].pack("U*")
expect(Emoji.lookup_unicode("family_man_woman_girl")).to eq(family_skinned)
end
end
describe ".lookup_unicode" do
it "returns unicode for emoji, aliases, and skin tones" do
expect(Emoji.lookup_unicode("trade_mark")).to eq("")
expect(Emoji.lookup_unicode("blonde_man")).to eq("👱‍♂️")
expect(Emoji.lookup_unicode("anger_right")).to eq("🗯")
expect(Emoji.lookup_unicode("blonde_woman:t6")).to eq("👱🏿‍♀️")
end
it "respects emoji deny list" do
SiteSetting.emoji_deny_list = "peach"
Emoji.clear_cache
expect(Emoji.lookup_unicode("peach")).not_to eq("🍑")
end
end
describe ".url_for" do
it "returns correct url for all input formats" do
url = "/images/emoji/twitter/blonde_woman.png?v=#{Emoji::EMOJI_VERSION}"
toned_url = "/images/emoji/twitter/blonde_woman/6.png?v=#{Emoji::EMOJI_VERSION}"
expect(Emoji.url_for("blonde_woman")).to eq(url)
expect(Emoji.url_for(":blonde_woman:")).to eq(url)
expect(Emoji.url_for("blonde_woman:t6")).to eq(toned_url)
expect(Emoji.url_for(":blonde_woman:t6:")).to eq(toned_url)
end
end
describe ".resolve_alias" do
it "resolves aliases to canonical names" do
expect(Emoji.resolve_alias("xray")).to eq("x_ray")
expect(Emoji.resolve_alias("blonde_woman")).to eq("blonde_woman")
end
end
describe "emoji lookup" do
it "finds emoji by name" do
expect(Emoji["blonde_woman"].name).to eq("blonde_woman")
expect(Emoji[":blonde_woman:"].name).to eq("blonde_woman")
expect(Emoji.exists?("blonde_woman")).to be(true)
expect(Emoji.exists?(":blonde_woman:")).to be(true)
end
it "finds emoji by alias" do
expect(Emoji["xray"].name).to eq("x_ray")
expect(Emoji[":xray:"].name).to eq("x_ray")
expect(Emoji.exists?("xray")).to be(true)
expect(Emoji.exists?(":xray:")).to be(true)
end
it "finds tonable emoji with skin tone" do
expect(Emoji["blonde_woman:t6"].name).to eq("blonde_woman")
expect(Emoji[":blonde_woman:t6:"].name).to eq("blonde_woman")
expect(Emoji.exists?("blonde_woman:t6")).to be(true)
expect(Emoji.exists?(":blonde_woman:t1:")).to be(true)
end
it "finds tonable emoji by alias with skin tone" do
expect(Emoji["basketball_man:t4"].name).to eq("man_bouncing_ball")
expect(Emoji[":basketball_man:t4:"].name).to eq("man_bouncing_ball")
expect(Emoji.exists?("basketball_man:t4")).to be(true)
expect(Emoji.exists?(":basketball_man:t4:")).to be(true)
end
it "finds custom emoji" do
CustomEmoji.create!(name: "test", upload_id: 9999)
Emoji.clear_cache
expect(Emoji.exists?("test")).to be(true)
expect(Emoji.exists?(":test:")).to be(true)
end
it "finds custom emoji with skin tone pattern in name" do
CustomEmoji.create!(name: "test:t1:foo", upload_id: 9999)
Emoji.clear_cache
expect(Emoji.exists?("test:t1:foo")).to be(true)
expect(Emoji.exists?(":test:t1:foo:")).to be(true)
end
it "returns nil/false for non-existing emoji" do
expect(Emoji["foo_bar_baz"]).to be_nil
expect(Emoji[":foo_bar_baz:"]).to be_nil
expect(Emoji.exists?(":foo-bar:")).to be(false)
end
it "returns nil/false for invalid skin tones" do
expect(Emoji["apple:t4"]).to be_nil
expect(Emoji.exists?(":blonde_woman:t7:")).to be(false)
expect(Emoji.exists?("blonde_woman:t0")).to be(false)
expect(Emoji.exists?("blonde_woman:t")).to be(false)
end
end
describe ".codes_to_img" do
before { Plugin::CustomEmoji.clear_cache }
after { Plugin::CustomEmoji.clear_cache }
it "replaces emoji codes by images" do
Plugin::CustomEmoji.register("xxxxxx", "/public/xxxxxx.png")
replaced_str = described_class.codes_to_img("This is a good day :xxxxxx: :woman: :man:t4:")
expect(replaced_str).to eq(<<~HTML.chomp)
This is a good day <img src="/public/xxxxxx.png" title="xxxxxx" class="emoji" alt="xxxxxx" loading="lazy" width="20" height="20"> <img src="/images/emoji/twitter/woman.png?v=#{Emoji::EMOJI_VERSION}" title="woman" class="emoji" alt="woman" loading="lazy" width="20" height="20"> <img src="/images/emoji/twitter/man/4.png?v=#{Emoji::EMOJI_VERSION}" title="man:t4" class="emoji" alt="man:t4" loading="lazy" width="20" height="20">
HTML
end
it "doesn't replace non-existing codes" do
replaced_str =
described_class.codes_to_img("This is a good day :woman: :foo: :bar:t4: :man:t8:")
expect(replaced_str).to eq(<<~HTML.chomp)
This is a good day <img src="/images/emoji/twitter/woman.png?v=#{Emoji::EMOJI_VERSION}" title="woman" class="emoji" alt="woman" loading="lazy" width="20" height="20"> :foo: :bar:t4: :man:t8:
HTML
end
end
describe ".groups" do
it "returns emoji name to group name mapping" do
expect(Emoji.groups["scotland"]).to eq("flags")
end
end
describe ".load_standard" do
it "removes nil emojis" do
expect(Emoji.load_standard.any?(&:nil?)).to be(false)
end
end
describe "#create_from_db_item" do
it "creates emoji with group when known" do
emoji = Emoji.create_from_db_item("name" => "scotland")
expect(emoji.group).to eq("flags")
end
it "returns nil when group is unknown" do
expect(Emoji.create_from_db_item("name" => "white_hair")).to be_nil
end
end
end