Constnium/node_modules/eslint-plugin-n/lib/util/merge-visitors-in-place.js

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2022-06-23 02:27:43 +02:00
/**
* @author Toru Nagashima <https://github.com/mysticatea>
* See LICENSE file in root directory for full license.
*/
"use strict"
/**
* Merge two visitors.
* This function modifies `visitor1` directly to merge.
* @param {Visitor} visitor1 The visitor which is assigned.
* @param {Visitor} visitor2 The visitor which is assigning.
* @returns {Visitor} `visitor1`.
*/
module.exports = function mergeVisitorsInPlace(visitor1, visitor2) {
for (const key of Object.keys(visitor2)) {
const handler1 = visitor1[key]
const handler2 = visitor2[key]
if (typeof handler1 === "function") {
if (handler1._handlers) {
handler1._handlers.push(handler2)
} else {
const handlers = [handler1, handler2]
visitor1[key] = Object.assign(dispatch.bind(null, handlers), {
_handlers: handlers,
})
}
} else {
visitor1[key] = handler2
}
}
return visitor1
}
/**
* Dispatch all given functions with a node.
* @param {function[]} handlers The function list to call.
* @param {Node} node The AST node to be handled.
* @returns {void}
*/
function dispatch(handlers, node) {
for (const h of handlers) {
h(node)
}
}