163 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			163 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| "use strict";
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| 
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| /**
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|  * @typedef {[number, boolean]} RangeValue
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|  */
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| 
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| /**
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|  * @callback RangeValueCallback
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|  * @param {RangeValue} rangeValue
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|  * @returns {boolean}
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|  */
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| class Range {
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|   /**
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|    * @param {"left" | "right"} side
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|    * @param {boolean} exclusive
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|    * @returns {">" | ">=" | "<" | "<="}
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|    */
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|   static getOperator(side, exclusive) {
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|     if (side === "left") {
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|       return exclusive ? ">" : ">=";
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|     }
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| 
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|     return exclusive ? "<" : "<=";
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|   }
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|   /**
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|    * @param {number} value
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|    * @param {boolean} logic is not logic applied
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|    * @param {boolean} exclusive is range exclusive
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|    * @returns {string}
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|    */
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| 
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| 
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|   static formatRight(value, logic, exclusive) {
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|     if (logic === false) {
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|       return Range.formatLeft(value, !logic, !exclusive);
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|     }
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| 
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|     return `should be ${Range.getOperator("right", exclusive)} ${value}`;
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|   }
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|   /**
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|    * @param {number} value
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|    * @param {boolean} logic is not logic applied
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|    * @param {boolean} exclusive is range exclusive
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|    * @returns {string}
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|    */
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| 
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| 
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|   static formatLeft(value, logic, exclusive) {
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|     if (logic === false) {
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|       return Range.formatRight(value, !logic, !exclusive);
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|     }
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| 
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|     return `should be ${Range.getOperator("left", exclusive)} ${value}`;
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|   }
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|   /**
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|    * @param {number} start left side value
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|    * @param {number} end right side value
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|    * @param {boolean} startExclusive is range exclusive from left side
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|    * @param {boolean} endExclusive is range exclusive from right side
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|    * @param {boolean} logic is not logic applied
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|    * @returns {string}
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|    */
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| 
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| 
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|   static formatRange(start, end, startExclusive, endExclusive, logic) {
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|     let result = "should be";
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|     result += ` ${Range.getOperator(logic ? "left" : "right", logic ? startExclusive : !startExclusive)} ${start} `;
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|     result += logic ? "and" : "or";
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|     result += ` ${Range.getOperator(logic ? "right" : "left", logic ? endExclusive : !endExclusive)} ${end}`;
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|     return result;
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|   }
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|   /**
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|    * @param {Array<RangeValue>} values
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|    * @param {boolean} logic is not logic applied
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|    * @return {RangeValue} computed value and it's exclusive flag
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|    */
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| 
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| 
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|   static getRangeValue(values, logic) {
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|     let minMax = logic ? Infinity : -Infinity;
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|     let j = -1;
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|     const predicate = logic ?
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|     /** @type {RangeValueCallback} */
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|     ([value]) => value <= minMax :
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|     /** @type {RangeValueCallback} */
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|     ([value]) => value >= minMax;
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| 
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|     for (let i = 0; i < values.length; i++) {
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|       if (predicate(values[i])) {
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|         [minMax] = values[i];
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|         j = i;
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|       }
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|     }
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| 
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|     if (j > -1) {
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|       return values[j];
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|     }
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| 
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|     return [Infinity, true];
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|   }
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| 
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|   constructor() {
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|     /** @type {Array<RangeValue>} */
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|     this._left = [];
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|     /** @type {Array<RangeValue>} */
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| 
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|     this._right = [];
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|   }
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|   /**
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|    * @param {number} value
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|    * @param {boolean=} exclusive
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|    */
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| 
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| 
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|   left(value, exclusive = false) {
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|     this._left.push([value, exclusive]);
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|   }
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|   /**
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|    * @param {number} value
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|    * @param {boolean=} exclusive
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|    */
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| 
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| 
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|   right(value, exclusive = false) {
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|     this._right.push([value, exclusive]);
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|   }
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|   /**
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|    * @param {boolean} logic is not logic applied
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|    * @return {string} "smart" range string representation
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|    */
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| 
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| 
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|   format(logic = true) {
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|     const [start, leftExclusive] = Range.getRangeValue(this._left, logic);
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|     const [end, rightExclusive] = Range.getRangeValue(this._right, !logic);
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| 
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|     if (!Number.isFinite(start) && !Number.isFinite(end)) {
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|       return "";
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|     }
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| 
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|     const realStart = leftExclusive ? start + 1 : start;
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|     const realEnd = rightExclusive ? end - 1 : end; // e.g. 5 < x < 7, 5 < x <= 6, 6 <= x <= 6
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| 
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|     if (realStart === realEnd) {
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|       return `should be ${logic ? "" : "!"}= ${realStart}`;
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|     } // e.g. 4 < x < ∞
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| 
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| 
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|     if (Number.isFinite(start) && !Number.isFinite(end)) {
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|       return Range.formatLeft(start, logic, leftExclusive);
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|     } // e.g. ∞ < x < 4
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| 
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| 
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|     if (!Number.isFinite(start) && Number.isFinite(end)) {
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|       return Range.formatRight(end, logic, rightExclusive);
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|     }
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| 
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|     return Range.formatRange(start, end, leftExclusive, rightExclusive, logic);
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|   }
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| 
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| }
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| 
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| module.exports = Range; |