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97 lines
2.7 KiB
JavaScript

5 years ago
"use strict";
exports.__esModule = true;
exports.visitor = undefined;
var _babelTypes = require("babel-types");
var t = _interopRequireWildcard(_babelTypes);
function _interopRequireWildcard(obj) { if (obj && obj.__esModule) { return obj; } else { var newObj = {}; if (obj != null) { for (var key in obj) { if (Object.prototype.hasOwnProperty.call(obj, key)) newObj[key] = obj[key]; } } newObj.default = obj; return newObj; } }
function getTDZStatus(refPath, bindingPath) {
var executionStatus = bindingPath._guessExecutionStatusRelativeTo(refPath);
if (executionStatus === "before") {
return "inside";
} else if (executionStatus === "after") {
return "outside";
} else {
return "maybe";
}
}
function buildTDZAssert(node, file) {
return t.callExpression(file.addHelper("temporalRef"), [node, t.stringLiteral(node.name), file.addHelper("temporalUndefined")]);
}
function isReference(node, scope, state) {
var declared = state.letReferences[node.name];
if (!declared) return false;
return scope.getBindingIdentifier(node.name) === declared;
}
var visitor = exports.visitor = {
ReferencedIdentifier: function ReferencedIdentifier(path, state) {
if (!this.file.opts.tdz) return;
var node = path.node,
parent = path.parent,
scope = path.scope;
if (path.parentPath.isFor({ left: node })) return;
if (!isReference(node, scope, state)) return;
var bindingPath = scope.getBinding(node.name).path;
var status = getTDZStatus(path, bindingPath);
if (status === "inside") return;
if (status === "maybe") {
var assert = buildTDZAssert(node, state.file);
bindingPath.parent._tdzThis = true;
path.skip();
if (path.parentPath.isUpdateExpression()) {
if (parent._ignoreBlockScopingTDZ) return;
path.parentPath.replaceWith(t.sequenceExpression([assert, parent]));
} else {
path.replaceWith(assert);
}
} else if (status === "outside") {
path.replaceWith(t.throwStatement(t.inherits(t.newExpression(t.identifier("ReferenceError"), [t.stringLiteral(node.name + " is not defined - temporal dead zone")]), node)));
}
},
AssignmentExpression: {
exit: function exit(path, state) {
if (!this.file.opts.tdz) return;
var node = path.node;
if (node._ignoreBlockScopingTDZ) return;
var nodes = [];
var ids = path.getBindingIdentifiers();
for (var name in ids) {
var id = ids[name];
if (isReference(id, path.scope, state)) {
nodes.push(buildTDZAssert(id, state.file));
}
}
if (nodes.length) {
node._ignoreBlockScopingTDZ = true;
nodes.push(node);
path.replaceWithMultiple(nodes.map(t.expressionStatement));
}
}
}
};