22 lines
553 B
JavaScript
22 lines
553 B
JavaScript
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/**
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* Copyright (c) 2013-present, Facebook, Inc.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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'use strict';
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const t = require('@babel/types');
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module.exports = function validateOutputAst(ast) {
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const seenNodes = new Set();
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t.traverseFast(ast, function enter(node) {
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if (seenNodes.has(node)) {
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throw new Error('Found a duplicate node in the output, which can cause'
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+ ' undefined behavior in Babel.');
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}
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seenNodes.add(node);
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})
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}
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