62 lines
1.5 KiB
TypeScript
62 lines
1.5 KiB
TypeScript
// Copyright 2021 Signal Messenger, LLC
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// SPDX-License-Identifier: AGPL-3.0-only
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import memoizee from 'memoizee';
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import { map, size, take, join } from './iterables.js';
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const getSegmenter = memoizee((): Intl.Segmenter => new Intl.Segmenter());
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export function getGraphemes(str: string): Iterable<string> {
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const segments = getSegmenter().segment(str);
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return map(segments, s => s.segment);
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}
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export function count(str: string): number {
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const segments = getSegmenter().segment(str);
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return size(segments);
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}
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/** @return truncated string and size (after any truncation) */
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export function truncateAndSize(
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str: string,
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toSize?: number
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): [string, number] {
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const segments = getSegmenter().segment(str);
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const originalSize = size(segments);
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if (toSize === undefined || originalSize <= toSize) {
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return [str, originalSize];
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}
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return [
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join(
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map(take(segments, toSize), s => s.segment),
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''
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),
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toSize,
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];
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}
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export function isSingleGrapheme(str: string): boolean {
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if (str === '') {
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return false;
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}
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const segments = getSegmenter().segment(str);
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return segments.containing(0).segment === str;
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}
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export function hasAtMostGraphemes(str: string, max: number): boolean {
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if (max < 0) {
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return false;
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}
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let countSoFar = 0;
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// eslint-disable-next-line @typescript-eslint/no-unused-vars
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for (const _ of getSegmenter().segment(str)) {
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countSoFar += 1;
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if (countSoFar > max) {
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return false;
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}
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}
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return true;
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}
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