105 lines
3.7 KiB
JavaScript
105 lines
3.7 KiB
JavaScript
var __defProp = Object.defineProperty;
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var __defNormalProp = (obj, key, value) => key in obj ? __defProp(obj, key, { enumerable: true, configurable: true, writable: true, value }) : obj[key] = value;
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var __publicField = (obj, key, value) => __defNormalProp(obj, typeof key !== "symbol" ? key + "" : key, value);
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// src/codeUtil.ts
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function isCodeHighSurrogate(code) {
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return Boolean(code && code >= 55296 && code <= 56319);
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}
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function isCodeLowSurrogate(code) {
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return Boolean(code && code >= 56320 && code <= 57343);
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}
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function tryGetGenuinePreviousCode(code, nowPoint, sliceSerialize) {
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if (nowPoint._bufferIndex < 2) {
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return code;
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}
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const previousBuffer = sliceSerialize({
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// take 2 characters (code units)
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start: { ...nowPoint, _bufferIndex: nowPoint._bufferIndex - 2 },
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end: nowPoint
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});
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const previousCandidate = previousBuffer.codePointAt(0);
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return previousCandidate && previousCandidate >= 65536 ? previousCandidate : code;
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}
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function tryGetCodeTwoBefore(previousCode, nowPoint, sliceSerialize) {
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const previousWidth = previousCode >= 65536 ? 2 : 1;
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if (nowPoint._bufferIndex < 1 + previousWidth) {
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return null;
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}
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const idealStart = nowPoint._bufferIndex - previousWidth - 2;
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const twoPreviousBuffer = sliceSerialize({
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// take 1--2 character
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start: {
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...nowPoint,
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_bufferIndex: idealStart >= 0 ? idealStart : 0
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},
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end: {
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...nowPoint,
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_bufferIndex: nowPoint._bufferIndex - previousWidth
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}
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});
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const twoPreviousLast = twoPreviousBuffer.charCodeAt(
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twoPreviousBuffer.length - 1
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);
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if (Number.isNaN(twoPreviousLast)) {
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return null;
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}
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if (twoPreviousBuffer.length < 2 || twoPreviousLast < 56320 || 57343 < twoPreviousLast) {
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return twoPreviousLast;
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}
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const twoPreviousCandidate = twoPreviousBuffer.codePointAt(0);
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if (twoPreviousCandidate && twoPreviousCandidate >= 65536) {
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return twoPreviousCandidate;
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}
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return twoPreviousLast;
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}
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var TwoPreviousCode = class {
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/**
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* @see {@link tryGetCodeTwoBefore}
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*
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* @param previousCode a previous code point. Should be greater than 65,535 if it represents a [Supplementary Character](https://www.unicode.org/glossary/#supplementary_character).
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* @param nowPoint `this.now()` (`this` = `TokenizeContext`)
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* @param sliceSerialize `this.sliceSerialize` (`this` = `TokenizeContext`)
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*/
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constructor(previousCode, nowPoint, sliceSerialize) {
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this.previousCode = previousCode;
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this.nowPoint = nowPoint;
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this.sliceSerialize = sliceSerialize;
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__publicField(this, "cachedValue");
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}
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/**
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* Returns the return value of {@link tryGetCodeTwoBefore}.
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*
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* If the value has not been computed yet, it will be computed and cached.
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*
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* @see {@link tryGetCodeTwoBefore}
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*
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* @returns a value greater than 65,535 if the code point two positions before represents a [Supplementary Character](https://www.unicode.org/glossary/#supplementary_character), a value less than 65,536 for a [BMP Character](https://www.unicode.org/glossary/#bmp_character), or `null` if not found
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*/
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value() {
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if (this.cachedValue === void 0) {
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this.cachedValue = tryGetCodeTwoBefore(
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this.previousCode,
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this.nowPoint,
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this.sliceSerialize
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);
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}
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return this.cachedValue;
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}
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};
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function tryGetGenuineNextCode(code, nowPoint, sliceSerialize) {
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const nextCandidate = sliceSerialize({
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start: nowPoint,
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end: { ...nowPoint, _bufferIndex: nowPoint._bufferIndex + 2 }
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}).codePointAt(0);
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return nextCandidate && nextCandidate >= 65536 ? nextCandidate : code;
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}
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export {
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TwoPreviousCode,
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isCodeHighSurrogate,
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isCodeLowSurrogate,
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tryGetCodeTwoBefore,
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tryGetGenuineNextCode,
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tryGetGenuinePreviousCode
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};
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