babel/lib/6to5/transformers/block-binding.js
2014-09-29 12:24:21 +10:00

65 lines
1.3 KiB
JavaScript

var traverse = require("../traverse");
var util = require("../util");
var _ = require("lodash");
var isLet = function (node) {
if (node.type === "VariableDeclaration" && node.kind === "let") {
node.kind = "var";
return true;
}
};
var hasLet = function (nodes) {
var has = false;
_.each(nodes, function (node) {
if (isLet(node)) has = true;
});
return has;
};
exports.Program = function (node) {
if (hasLet(node.body)) {
node.body = [buildNode(node.body)];
}
};
exports.BlockStatement = function (node, parent) {
if (!hasLet(node.body)) return;
// ignore if we're the body of a closure already
if (parent.type === "FunctionExpression") return;
node.body = [buildNode(node.body)];
};
exports.ForInStatement = function (node) {
if (isLet(node.left)) return buildNode(node);
};
exports.ForStatement = function (node) {
if (isLet(node.init)) return buildNode(node);
};
var buildNode = function (node) {
var func = {
type: "FunctionExpression",
params: [],
defaults: [],
body: {
type: "BlockStatement",
body: [].concat(node)
}
};
var templateName = "function-call";
if (traverse.hasType(node, "ThisExpression")) {
templateName = "function-call-this";
}
return util.template(templateName, {
FUNCTION: func
}, true);
};