Urara-Blog/node_modules/.pnpm-store/v3/files/29/d9be8d1f8c686ebca1a20d564c4e3a26a164638f0959b2740634e3eeef99976bbee1fa0ad248c659635bd162b7dad1b12760cbaf60b9725b99f1adcb77ffc5
2022-08-14 01:14:53 +08:00

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import * as regex from '../lib/regex'
/**
* This splits a string on a top-level character.
*
* Regex doesn't support recursion (at least not the JS-flavored version).
* So we have to use a tiny state machine to keep track of paren placement.
*
* Expected behavior using commas:
* var(--a, 0 0 1px rgb(0, 0, 0)), 0 0 1px rgb(0, 0, 0)
* ─┬─ ┬ ┬ ┬
* x x x ╰──────── Split because top-level
* ╰──────────────┴──┴───────────── Ignored b/c inside >= 1 levels of parens
*
* @param {string} input
* @param {string} separator
*/
export function* splitAtTopLevelOnly(input, separator) {
let SPECIALS = new RegExp(`[(){}\\[\\]${regex.escape(separator)}]`, 'g')
let depth = 0
let lastIndex = 0
let found = false
let separatorIndex = 0
let separatorStart = 0
let separatorLength = separator.length
// Find all paren-like things & character
// And only split on commas if they're top-level
for (let match of input.matchAll(SPECIALS)) {
let matchesSeparator = match[0] === separator[separatorIndex]
let atEndOfSeparator = separatorIndex === separatorLength - 1
let matchesFullSeparator = matchesSeparator && atEndOfSeparator
if (match[0] === '(') depth++
if (match[0] === ')') depth--
if (match[0] === '[') depth++
if (match[0] === ']') depth--
if (match[0] === '{') depth++
if (match[0] === '}') depth--
if (matchesSeparator && depth === 0) {
if (separatorStart === 0) {
separatorStart = match.index
}
separatorIndex++
}
if (matchesFullSeparator && depth === 0) {
found = true
yield input.substring(lastIndex, separatorStart)
lastIndex = separatorStart + separatorLength
}
if (separatorIndex === separatorLength) {
separatorIndex = 0
separatorStart = 0
}
}
// Provide the last segment of the string if available
// Otherwise the whole string since no `char`s were found
// This mirrors the behavior of string.split()
if (found) {
yield input.substring(lastIndex)
} else {
yield input
}
}