29 lines
1.2 KiB
JavaScript
29 lines
1.2 KiB
JavaScript
import { determineEmojiSupportLevel } from './determineEmojiSupportLevel'
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import { requestIdleCallback } from './requestIdleCallback.js'
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// Check which emojis we know for sure aren't supported, based on Unicode version level
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let promise
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export const detectEmojiSupportLevel = () => {
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if (!promise) {
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// Delay so it can run while the IDB database is being created by the browser (on another thread).
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// This helps especially with first load – we want to start pre-populating the database on the main thread,
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// and then wait for IDB to commit everything, and while waiting we run this check.
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promise = new Promise(resolve => (
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requestIdleCallback(() => (
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resolve(determineEmojiSupportLevel()) // delay so ideally this can run while IDB is first populating
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))
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))
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/* istanbul ignore else */
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if (process.env.NODE_ENV !== 'production') {
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promise.then(emojiSupportLevel => {
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console.log('emoji support level', emojiSupportLevel)
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})
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}
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}
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return promise
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}
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// determine which emojis containing ZWJ (zero width joiner) characters
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// are supported (rendered as one glyph) rather than unsupported (rendered as two or more glyphs)
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export const supportedZwjEmojis = new Map()
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