identical-links-same-purpose-after.js

/**
 * Skip unless there are more than a single result
 */
if (results.length < 2) {
	return results;
}

/**
 * for each result
 * - get other results with matching accessible name
 * - check if same purpose is served
 *  - if not change `result` to `undefined`
 */
for (let i = 0; i < results.length; i++) {
	const { accessibleText, linkResource } = results[i].data;
	const resourceLocation = linkResource.split('/').pop();

	const matchingIndices = getIndicesOfLinksWithMatchingAccessibleText(
		accessibleText,
		i
	);
	const identicalLinks = matchingIndices.map(index => results[index]);

	if (!hasSamePurpose(resourceLocation, identicalLinks)) {
		results[i].result = undefined;
	}
}

return results;

/**
 * Get list of items from results which match a prescribed accessible name
 * @param {String} expectedAccessibleText accessible name to be matched
 * @param {Number} excludeIndex exclude `index` of result, that should not be taken into consideration
 * @returns {Array<Number>}
 */
function getIndicesOfLinksWithMatchingAccessibleText(
	expectedAccessibleText,
	excludeIndex
) {
	return results
		.map(({ data: { accessibleText } }, index) => {
			if (index !== excludeIndex && accessibleText === expectedAccessibleText) {
				return index;
			}
		})
		.filter(value => typeof value !== 'undefined');
}

/**
 * Check if a given set of links have same resource
 * @param {String} expectedResource resource string
 * @param {Array<Object>} identicalLinks results where `data.accessibleText` were identical
 * @returns {Boolean}
 */
function hasSamePurpose(expectedResource, identicalLinks) {
	return identicalLinks.every(({ data: { linkResource } }) => {
		const resource = linkResource.split('/').pop();
		return expectedResource.includes(resource);
	});
}