82 lines
1.8 KiB
JavaScript
82 lines
1.8 KiB
JavaScript
import TraversalPath from "./path";
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import compact from "lodash/array/compact";
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import * as t from "../types";
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export default class TraversalContext {
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constructor(scope, opts, state, parentPath) {
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this.parentPath = parentPath;
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this.scope = scope;
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this.state = state;
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this.opts = opts;
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}
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shouldVisit(node) {
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var keys = t.VISITOR_KEYS[node.type];
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return !!(this.opts.enter || this.opts.exit || this.opts[node.type] || (keys && keys.length));
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}
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create(node, obj, key) {
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var path = TraversalPath.get(this.parentPath, node, obj, key);
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path.unshiftContext(this);
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return path;
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}
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visitMultiple(nodes, node, key) {
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// nothing to traverse!
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if (nodes.length === 0) return false;
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var visited = [];
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var queue = this.queue = [];
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var stop = false;
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// build up initial queue
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for (let i = 0; i < nodes.length; i++) {
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var self = nodes[i];
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if (self && this.shouldVisit(self)) {
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queue.push(this.create(node, nodes, i));
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}
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}
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// visit the queue
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for (let path of (queue: Array)) {
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path.update();
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if (visited.indexOf(path.node) >= 0) continue;
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visited.push(path.node);
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if (path.visit()) {
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stop = true;
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break;
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}
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}
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for (let path of (queue: Array)) {
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path.shiftContext();
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}
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this.queue = null;
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return stop;
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}
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visitSingle(node, key) {
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if (this.shouldVisit(node[key])) {
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var path = this.create(node, node, key);
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path.visit();
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path.shiftContext();
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}
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}
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visit(node, key) {
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var nodes = node[key];
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if (!nodes) return;
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if (Array.isArray(nodes)) {
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return this.visitMultiple(nodes, node, key);
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} else {
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return this.visitSingle(node, key);
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}
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}
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}
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