66 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
/**
 | 
						|
 * @author Toru Nagashima <https://github.com/mysticatea>
 | 
						|
 * See LICENSE file in root directory for full license.
 | 
						|
 */
 | 
						|
import KEYS from "./visitor-keys.js";
 | 
						|
 | 
						|
/**
 | 
						|
 * @typedef {import('./visitor-keys.js').VisitorKeys} VisitorKeys
 | 
						|
 */
 | 
						|
 | 
						|
// List to ignore keys.
 | 
						|
const KEY_BLACKLIST = new Set([
 | 
						|
    "parent",
 | 
						|
    "leadingComments",
 | 
						|
    "trailingComments"
 | 
						|
]);
 | 
						|
 | 
						|
/**
 | 
						|
 * Check whether a given key should be used or not.
 | 
						|
 * @param {string} key The key to check.
 | 
						|
 * @returns {boolean} `true` if the key should be used.
 | 
						|
 */
 | 
						|
function filterKey(key) {
 | 
						|
    return !KEY_BLACKLIST.has(key) && key[0] !== "_";
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
 * Get visitor keys of a given node.
 | 
						|
 * @param {object} node The AST node to get keys.
 | 
						|
 * @returns {readonly string[]} Visitor keys of the node.
 | 
						|
 */
 | 
						|
export function getKeys(node) {
 | 
						|
    return Object.keys(node).filter(filterKey);
 | 
						|
}
 | 
						|
 | 
						|
// Disable valid-jsdoc rule because it reports syntax error on the type of @returns.
 | 
						|
// eslint-disable-next-line valid-jsdoc
 | 
						|
/**
 | 
						|
 * Make the union set with `KEYS` and given keys.
 | 
						|
 * @param {VisitorKeys} additionalKeys The additional keys.
 | 
						|
 * @returns {VisitorKeys} The union set.
 | 
						|
 */
 | 
						|
export function unionWith(additionalKeys) {
 | 
						|
    const retv = /** @type {{
 | 
						|
        [type: string]: ReadonlyArray<string>
 | 
						|
    }} */ (Object.assign({}, KEYS));
 | 
						|
 | 
						|
    for (const type of Object.keys(additionalKeys)) {
 | 
						|
        if (Object.prototype.hasOwnProperty.call(retv, type)) {
 | 
						|
            const keys = new Set(additionalKeys[type]);
 | 
						|
 | 
						|
            for (const key of retv[type]) {
 | 
						|
                keys.add(key);
 | 
						|
            }
 | 
						|
 | 
						|
            retv[type] = Object.freeze(Array.from(keys));
 | 
						|
        } else {
 | 
						|
            retv[type] = Object.freeze(Array.from(additionalKeys[type]));
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    return Object.freeze(retv);
 | 
						|
}
 | 
						|
 | 
						|
export { KEYS };
 |