ecmarkup/lib/lint/rules/for-each-of.js

Custom element definitions and core utilities for markup that specifies ECMAScript and related technologies.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.default = default_1;
const utils_1 = require("../../utils");
const ruleId = 'for-each-of';
/*
Checks that "For each" loops use "of", not "in".
Exception: iterating over an interval, e.g. "in the inclusive interval from _a_ to _b_", correctly uses "in".
*/
function default_1(report, step, algorithmSource, parsedSteps) {
    const stepSeq = parsedSteps.get(step);
    if (stepSeq == null || stepSeq.items.length < 3) {
        return;
    }
    const first = stepSeq.items[0];
    if (!(first.name === 'text' && first.contents.startsWith('For each '))) {
        return;
    }
    // Find the loop variable (underscore), then check the text after it
    for (let i = 1; i < stepSeq.items.length - 1; i++) {
        const item = stepSeq.items[i];
        if (item.name !== 'underscore') {
            continue;
        }
        const next = stepSeq.items[i + 1];
        if (next.name === 'text' &&
            /^ in\b/.test(next.contents) &&
            // Iterating over an interval is a valid construction where "in" is correct, in either the
            // "inclusive interval from _a_ to _b_" shorthand or the full "interval from _a_ ... to _b_ ..." form.
            !/^ in the (?:inclusive )?interval\b/.test(next.contents)) {
            report({
                ruleId,
                ...(0, utils_1.offsetToLineAndColumn)(algorithmSource, next.location.start.offset + 1),
                message: 'expected "of" instead of "in" in "for each"',
            });
        }
        break;
    }
}