feat: emoji detection and tests TryQuiet#519

packages/common/src/emojis.test.ts

@@ -0,0 +1,22 @@
+import { hasEmoji, isAllEmoji } from './emojis'
+
+describe('Emoji Utilities', () => {
+  it('Should detect an emoji in a string', () => {
+    expect(hasEmoji('❤️‍🔥')).toBeTruthy()
+    expect(hasEmoji('Hello ❤️‍🔥 Emoji')).toBeTruthy()
+    expect(hasEmoji('No emoji :-(')).toBeFalsy()
+  })
+
+  it('Should detect when a string is all emojis (or spaces)', () => {
+    expect(isAllEmoji('🙂🙂🙂🙂🙂🙂🙂🙂')).toBeTruthy()
+    expect(isAllEmoji('🐈‍⬛❤️‍🔥🏴')).toBeTruthy()
+    expect(isAllEmoji('🐈‍⬛ ❤️‍🔥 🏴')).toBeTruthy()
+    expect(isAllEmoji('❤️‍🔥')).toBeTruthy()
+    expect(isAllEmoji('🐈‍⬛')).toBeTruthy()
+    expect(isAllEmoji('❤️‍🔥 Emoji')).toBeFalsy()
+    expect(isAllEmoji('Hello ❤️‍🔥')).toBeFalsy()
+    expect(isAllEmoji('Hello ❤️‍🔥 Emoji')).toBeFalsy()
+    expect(isAllEmoji('🐈‍⬛ (Not emoji) 🏴')).toBeFalsy()
+    expect(isAllEmoji('No emoji :-(')).toBeFalsy()
+  })
+})

packages/common/src/emojis.ts

@@ -0,0 +1,12 @@
+export const hasEmoji = (testString: string) => {
+  // All strings with at least one emoji character should match this
+  const regExp = /\p{Emoji}/gu
+  return regExp.test(testString)
+}
+
+export const isAllEmoji = (testString: string) => {
+  // Detect whether a string is entirely emojis (and whitespace and zero-width-joins, region indicators, etc)
+  // This may need to be updated as Unicode's Emoji spec is a moving target
+  const emojiOrWhitespaceRegExp = /^(\p{Emoji}|\p{Emoji_Modifier}|\uFE0F|\u200D|\p{RI}|\uE007F|\s)+$/gu
+  return emojiOrWhitespaceRegExp.test(testString)
+}