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