File size: 1,549 Bytes
767b82d | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 | /**
* @fileoverview Utilities to operate on strings.
* @author Stephen Wade
*/
"use strict";
//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------
// eslint-disable-next-line no-control-regex -- intentionally including control characters
const ASCII_REGEX = /^[\u0000-\u007f]*$/u;
/** @type {Intl.Segmenter | undefined} */
let segmenter;
//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------
/**
* Converts the first letter of a string to uppercase.
* @param {string} string The string to operate on
* @returns {string} The converted string
*/
function upperCaseFirst(string) {
if (string.length <= 1) {
return string.toUpperCase();
}
return string[0].toUpperCase() + string.slice(1);
}
/**
* Counts graphemes in a given string.
* @param {string} value A string to count graphemes.
* @returns {number} The number of graphemes in `value`.
*/
function getGraphemeCount(value) {
if (ASCII_REGEX.test(value)) {
return value.length;
}
segmenter ??= new Intl.Segmenter("en-US"); // en-US locale should be supported everywhere
let graphemeCount = 0;
// eslint-disable-next-line no-unused-vars -- for-of needs a variable
for (const unused of segmenter.segment(value)) {
graphemeCount++;
}
return graphemeCount;
}
module.exports = {
upperCaseFirst,
getGraphemeCount,
};
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