forked from zhurui/management
91 lines
2.3 KiB
JavaScript
91 lines
2.3 KiB
JavaScript
|
import { createPath } from "./node-path";
|
||
|
|
import { unionTypesMap, nodeAndUnionTypes } from "./nodes"; // recursively walks the AST starting at the given node. The callback is invoked for
|
||
|
|
// and object that has a 'type' property.
|
||
|
|
|
||
|
|
function walk(context, callback) {
|
||
|
|
var stop = false;
|
||
|
|
|
||
|
|
function innerWalk(context, callback) {
|
||
|
|
if (stop) {
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
var node = context.node;
|
||
|
|
|
||
|
|
if (node._deleted === true) {
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
var path = createPath(context);
|
||
|
|
callback(node.type, path);
|
||
|
|
|
||
|
|
if (path.shouldStop) {
|
||
|
|
stop = true;
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
Object.keys(node).forEach(function (prop) {
|
||
|
|
var value = node[prop];
|
||
|
|
|
||
|
|
if (value === null || value === undefined) {
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
var valueAsArray = Array.isArray(value) ? value : [value];
|
||
|
|
valueAsArray.forEach(function (childNode) {
|
||
|
|
if (typeof childNode.type === "string") {
|
||
|
|
var childContext = {
|
||
|
|
node: childNode,
|
||
|
|
parentKey: prop,
|
||
|
|
parentPath: path,
|
||
|
|
shouldStop: false,
|
||
|
|
inList: Array.isArray(value)
|
||
|
|
};
|
||
|
|
innerWalk(childContext, callback);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
innerWalk(context, callback);
|
||
|
|
}
|
||
|
|
|
||
|
|
var noop = function noop() {};
|
||
|
|
|
||
|
|
export function traverse(node, visitors) {
|
||
|
|
var before = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : noop;
|
||
|
|
var after = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : noop;
|
||
|
|
Object.keys(visitors).forEach(function (visitor) {
|
||
|
|
if (!nodeAndUnionTypes.includes(visitor)) {
|
||
|
|
throw new Error("Unexpected visitor ".concat(visitor));
|
||
|
|
}
|
||
|
|
});
|
||
|
|
var context = {
|
||
|
|
node: node,
|
||
|
|
inList: false,
|
||
|
|
shouldStop: false,
|
||
|
|
parentPath: null,
|
||
|
|
parentKey: null
|
||
|
|
};
|
||
|
|
walk(context, function (type, path) {
|
||
|
|
if (typeof visitors[type] === "function") {
|
||
|
|
before(type, path);
|
||
|
|
visitors[type](path);
|
||
|
|
after(type, path);
|
||
|
|
}
|
||
|
|
|
||
|
|
var unionTypes = unionTypesMap[type];
|
||
|
|
|
||
|
|
if (!unionTypes) {
|
||
|
|
throw new Error("Unexpected node type ".concat(type));
|
||
|
|
}
|
||
|
|
|
||
|
|
unionTypes.forEach(function (unionType) {
|
||
|
|
if (typeof visitors[unionType] === "function") {
|
||
|
|
before(unionType, path);
|
||
|
|
visitors[unionType](path);
|
||
|
|
after(unionType, path);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
});
|
||
|
|
}
|