babel/lib/6to5/traversal/context.js

79 lines
1.6 KiB
JavaScript

"use strict";
/* jshint maxparams:7 */
module.exports = TraversalContext;
var TraversalPath = require("./path");
var flatten = require("lodash/array/flatten");
var compact = require("lodash/array/compact");
function TraversalContext(scope, opts, state) {
this.shouldFlatten = false;
this.scope = scope;
this.state = state;
this.opts = opts;
this.reset();
}
TraversalContext.prototype.flatten = function () {
this.shouldFlatten = true;
};
TraversalContext.prototype.remove = function () {
this.shouldRemove = true;
this.shouldSkip = true;
};
TraversalContext.prototype.skip = function () {
this.shouldSkip = true;
};
TraversalContext.prototype.stop = function () {
this.shouldStop = true;
this.shouldSkip = true;
};
TraversalContext.prototype.reset = function () {
this.shouldRemove = false;
this.shouldSkip = false;
this.shouldStop = false;
};
TraversalContext.prototype.visitNode = function (node, obj, key) {
this.reset();
var iteration = new TraversalPath(this, node, obj, key);
return iteration.visit();
};
TraversalContext.prototype.visit = function (node, key) {
var nodes = node[key];
if (!nodes) return;
if (!Array.isArray(nodes)) {
return this.visitNode(node, node, key);
}
// nothing to traverse!
if (nodes.length === 0) {
return;
}
for (var i = 0; i < nodes.length; i++) {
if (nodes[i] && this.visitNode(node, nodes, i)) {
return true;
}
}
if (this.shouldFlatten) {
node[key] = flatten(node[key]);
if (key === "body") {
// we can safely compact this
node[key] = compact(node[key]);
}
}
};