@yusufkandemir/eslint-plugin-lodash-template/lib/services/source-code-store.js

ESLint plugin for John Resig-style micro template, Lodash's template, Underscore's template and EJS.

"use strict";

/**
 * _.sortedLastIndex
 *
 * @param {Array} array The sorted array to inspect.
 * @param {*} value The value to evaluate.
 * @returns {number} Returns the index at which `value` should be inserted
 *  into `array`.
 */
function sortedLastIndexForNum(array, value) {
    let low = 0;
    let high = array == null ? low : array.length;

    while (low < high) {
        const mid = (low + high) >>> 1;
        const computed = array[mid];
        if (computed <= value) {
            low = mid + 1;
        } else {
            high = mid;
        }
    }
    return high;
}

module.exports = class SourceCodeStore {
    /**
     * constructor
     * @param {string} code The source code.
     */
    constructor(code) {
        const lineStartIndices = [0];

        let match = undefined;
        const lineEndingPattern = /\r\n|[\n\r\u2028\u2029]/gu;
        while ((match = lineEndingPattern.exec(code))) {
            lineStartIndices.push(match.index + match[0].length);
        }

        this.text = code;
        this._lineStartIndices = lineStartIndices;
    }

    /**
     * Converts a source text index into a (line, column) pair.
     * @param {number} index The index of a character in a file
     * @returns {object} A {line, column} location object with a 0-indexed column
     */
    getLocFromIndex(index) {
        const code = this.text;
        const lineStartIndices = this._lineStartIndices;
        if (index === code.length) {
            return {
                line: lineStartIndices.length,
                column: index - lineStartIndices[lineStartIndices.length - 1],
            };
        }
        const lineNumber = sortedLastIndexForNum(lineStartIndices, index);

        return {
            line: lineNumber,
            column: index - lineStartIndices[lineNumber - 1],
        };
    }

    /**
     * Converts a (line, column) pair into a range index.
     * @param {Object} loc A line/column location
     * @param {number} loc.line The line number of the location (1-indexed)
     * @param {number} loc.column The column number of the location (0-indexed)
     * @returns {number} The range index of the location in the file.
     * @public
     */
    getIndexFromLoc(loc) {
        const lineStartIndices = this._lineStartIndices;
        const lineStartIndex = lineStartIndices[loc.line - 1];
        const positionIndex = lineStartIndex + loc.column;

        return positionIndex;
    }

    /**
     * Get a character string extracted only the template part from the whole source code.
     * @returns {string} The template.
     */
    get template() {
        return this._template;
    }

    /**
     * Set a character string extracted only the template part from the whole source code.
     * @param  {string} template  The template
     * @returns {void}
     */
    set template(template) {
        this._template = template;
    }

    /**
     * Get a character string extracted only the script part from the whole source code.
     * @returns {string} The script.
     */
    get script() {
        return this._script;
    }

    /**
     * Set a character string extracted only the script part from the whole source code.
     * @param  {string} script  The script
     * @returns {void}
     */
    set script(script) {
        this._script = script;
    }
};