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| author | Adam Mathes <adam@adammathes.com> | 2026-02-13 21:34:48 -0800 |
|---|---|---|
| committer | Adam Mathes <adam@adammathes.com> | 2026-02-13 21:34:48 -0800 |
| commit | 76cb9c2a39d477a64824a985ade40507e3bbade1 (patch) | |
| tree | 41e997aa9c6f538d3a136af61dae9424db2005a9 /vanilla/node_modules/@exodus/bytes/base64.js | |
| parent | 819a39a21ac992b1393244a4c283bbb125208c69 (diff) | |
| download | neko-76cb9c2a39d477a64824a985ade40507e3bbade1.tar.gz neko-76cb9c2a39d477a64824a985ade40507e3bbade1.tar.bz2 neko-76cb9c2a39d477a64824a985ade40507e3bbade1.zip | |
feat(vanilla): add testing infrastructure and tests (NK-wjnczv)
Diffstat (limited to 'vanilla/node_modules/@exodus/bytes/base64.js')
| -rw-r--r-- | vanilla/node_modules/@exodus/bytes/base64.js | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/vanilla/node_modules/@exodus/bytes/base64.js b/vanilla/node_modules/@exodus/bytes/base64.js new file mode 100644 index 0000000..e8625f7 --- /dev/null +++ b/vanilla/node_modules/@exodus/bytes/base64.js @@ -0,0 +1,178 @@ +import { assertEmptyRest } from './assert.js' +import { typedView } from './array.js' +import { assertU8, E_STRING } from './fallback/_utils.js' +import { isHermes } from './fallback/platform.js' +import { decodeLatin1, encodeLatin1 } from './fallback/latin1.js' +import * as js from './fallback/base64.js' + +// See https://datatracker.ietf.org/doc/html/rfc4648 + +// base64: A-Za-z0-9+/ and = if padding not disabled +// base64url: A-Za-z0-9_- and = if padding enabled + +const { Buffer, atob, btoa } = globalThis // Buffer is optional, only used when native +const haveNativeBuffer = Buffer && !Buffer.TYPED_ARRAY_SUPPORT +const { toBase64: web64 } = Uint8Array.prototype // Modern engines have this + +const { E_CHAR, E_PADDING, E_LENGTH, E_LAST } = js + +// faster only on Hermes (and a little in old Chrome), js path beats it on normal engines +const shouldUseBtoa = btoa && isHermes +const shouldUseAtob = atob && isHermes + +// For native Buffer codepaths only +const isBuffer = (x) => x.constructor === Buffer && Buffer.isBuffer(x) +const toBuffer = (x) => (isBuffer(x) ? x : Buffer.from(x.buffer, x.byteOffset, x.byteLength)) + +function maybeUnpad(res, padding) { + if (padding) return res + const at = res.indexOf('=', res.length - 3) + return at === -1 ? res : res.slice(0, at) +} + +function maybePad(res, padding) { + return padding && res.length % 4 !== 0 ? res + '='.repeat(4 - (res.length % 4)) : res +} + +const toUrl = (x) => x.replaceAll('+', '-').replaceAll('/', '_') +const haveWeb = (x) => web64 && x.toBase64 === web64 + +export function toBase64(x, { padding = true } = {}) { + assertU8(x) + if (haveWeb(x)) return padding ? x.toBase64() : x.toBase64({ omitPadding: !padding }) // Modern, optionless is slightly faster + if (haveNativeBuffer) return maybeUnpad(toBuffer(x).base64Slice(0, x.byteLength), padding) // Older Node.js + if (shouldUseBtoa) return maybeUnpad(btoa(decodeLatin1(x)), padding) + return js.toBase64(x, false, padding) // Fallback +} + +// NOTE: base64url omits padding by default +export function toBase64url(x, { padding = false } = {}) { + assertU8(x) + if (haveWeb(x)) return x.toBase64({ alphabet: 'base64url', omitPadding: !padding }) // Modern + if (haveNativeBuffer) return maybePad(toBuffer(x).base64urlSlice(0, x.byteLength), padding) // Older Node.js + if (shouldUseBtoa) return maybeUnpad(toUrl(btoa(decodeLatin1(x))), padding) + return js.toBase64(x, true, padding) // Fallback +} + +// Unlike Buffer.from(), throws on invalid input (non-base64 symbols and incomplete chunks) +// Unlike Buffer.from() and Uint8Array.fromBase64(), does not allow spaces +// NOTE: Always operates in strict mode for last chunk + +// By default accepts both padded and non-padded variants, only strict base64 +export function fromBase64(str, options) { + if (typeof options === 'string') options = { format: options } // Compat due to usage, TODO: remove + if (!options) return fromBase64common(str, false, 'both', 'uint8', null) + const { format = 'uint8', padding = 'both', ...rest } = options + return fromBase64common(str, false, padding, format, rest) +} + +// By default accepts only non-padded strict base64url +export function fromBase64url(str, options) { + if (!options) return fromBase64common(str, true, false, 'uint8', null) + const { format = 'uint8', padding = false, ...rest } = options + return fromBase64common(str, true, padding, format, rest) +} + +// By default accepts both padded and non-padded variants, base64 or base64url +export function fromBase64any(str, { format = 'uint8', padding = 'both', ...rest } = {}) { + const isBase64url = !str.includes('+') && !str.includes('/') // likely to fail fast, as most input is non-url, also double scan is faster than regex + return fromBase64common(str, isBase64url, padding, format, rest) +} + +function fromBase64common(str, isBase64url, padding, format, rest) { + if (typeof str !== 'string') throw new TypeError(E_STRING) + if (rest !== null) assertEmptyRest(rest) + const auto = padding === 'both' ? str.endsWith('=') : undefined + // Older JSC supporting Uint8Array.fromBase64 lacks proper checks + if (padding === true || auto === true) { + if (str.length % 4 !== 0) throw new SyntaxError(E_PADDING) // JSC misses this + if (str[str.length - 3] === '=') throw new SyntaxError(E_PADDING) // no more than two = at the end + } else if (padding === false || auto === false) { + if (str.length % 4 === 1) throw new SyntaxError(E_LENGTH) // JSC misses this in fromBase64 + if (padding === false && str.endsWith('=')) { + throw new SyntaxError('Did not expect padding in base64 input') // inclusion is checked separately + } + } else { + throw new TypeError('Invalid padding option') + } + + return typedView(fromBase64impl(str, isBase64url, padding), format) +} + +// ASCII whitespace is U+0009 TAB, U+000A LF, U+000C FF, U+000D CR, or U+0020 SPACE +const ASCII_WHITESPACE = /[\t\n\f\r ]/ // non-u for JSC perf + +function noWhitespaceSeen(str, arr) { + const at = str.indexOf('=', str.length - 3) + const paddingLength = at >= 0 ? str.length - at : 0 + const chars = str.length - paddingLength + const e = chars % 4 // extra chars past blocks of 4 + const b = arr.length - ((chars - e) / 4) * 3 // remaining bytes not covered by full blocks of chars + return (e === 0 && b === 0) || (e === 2 && b === 1) || (e === 3 && b === 2) +} + +let fromBase64impl +if (Uint8Array.fromBase64) { + // NOTICE: this is actually slower than our JS impl in older JavaScriptCore and (slightly) in SpiderMonkey, but faster on V8 and new JavaScriptCore + fromBase64impl = (str, isBase64url, padding) => { + const alphabet = isBase64url ? 'base64url' : 'base64' + + let arr + if (padding === true) { + // Padding is required from user, and we already checked that string length is divisible by 4 + // Padding might still be wrong due to whitespace, but in that case native impl throws expected error + arr = Uint8Array.fromBase64(str, { alphabet, lastChunkHandling: 'strict' }) + } else { + try { + const padded = str.length % 4 > 0 ? `${str}${'='.repeat(4 - (str.length % 4))}` : str + arr = Uint8Array.fromBase64(padded, { alphabet, lastChunkHandling: 'strict' }) + } catch (err) { + // Normalize error: whitespace in input could have caused added padding to be invalid + // But reporting that as a padding error would be confusing + throw ASCII_WHITESPACE.test(str) ? new SyntaxError(E_CHAR) : err + } + } + + // We don't allow whitespace in input, but that can be rechecked based on output length + // All other chars are checked natively + if (!noWhitespaceSeen(str, arr)) throw new SyntaxError(E_CHAR) + return arr + } +} else if (haveNativeBuffer) { + fromBase64impl = (str, isBase64url, padding) => { + const arr = Buffer.from(str, 'base64') + // Rechecking by re-encoding is cheaper than regexes on Node.js + const got = isBase64url ? maybeUnpad(str, padding === false) : maybePad(str, padding !== true) + const valid = isBase64url ? arr.base64urlSlice(0, arr.length) : arr.base64Slice(0, arr.length) + if (got !== valid) throw new SyntaxError(E_PADDING) + return arr // fully checked + } +} else if (shouldUseAtob) { + // atob is faster than manual parsing on Hermes + fromBase64impl = (str, isBase64url, padding) => { + let arr + if (isBase64url) { + if (/[\t\n\f\r +/]/.test(str)) throw new SyntaxError(E_CHAR) // atob verifies other invalid input + str = str.replaceAll('-', '+').replaceAll('_', '/') // from url to normal + } + + try { + arr = encodeLatin1(atob(str)) + } catch { + throw new SyntaxError(E_CHAR) // convert atob errors + } + + if (!isBase64url && !noWhitespaceSeen(str, arr)) throw new SyntaxError(E_CHAR) // base64url checks input above + + if (arr.length % 3 !== 0) { + // Check last chunk to be strict if it was incomplete + const expected = toBase64(arr.subarray(-(arr.length % 3))) // str is normalized to non-url already + const end = str.length % 4 === 0 ? str.slice(-4) : str.slice(-(str.length % 4)).padEnd(4, '=') + if (expected !== end) throw new SyntaxError(E_LAST) + } + + return arr + } +} else { + fromBase64impl = (str, isBase64url, padding) => js.fromBase64(str, isBase64url) // validated in js +} |
