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transformObjectKeys=true causes obfuscator to crash with "TypeError: Cannot read property 'type' of undefined" if input code contains object spread operator

See original GitHub issue

var JavaScriptObfuscator = require('javascript-obfuscator');

var obfuscationResult = JavaScriptObfuscator.obfuscate(
	`
        var obj1={
		firstname:'John',
		lastname:'Smith'
	};
	var obj2={
		age:40,
		country:'USA'
	}
	var user={...obj1, ...obj2}
	console.log(user);

    `,
	{
		transformObjectKeys: true,
	}
);

console.log(obfuscationResult.getObfuscatedCode());

Expected Behavior

The normal ouput of this program is:

{firstname: "John", lastname: "Smith", age: 40, country: "USA"}

Current Behavior

The current behavior is:

/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node/NodeGuards.ts:270
        return node.type === NodeType.ObjectPattern;
                    ^
TypeError: Cannot read property 'type' of undefined
    at Function.type (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node/NodeGuards.ts:270:21)
    at Function.isObjectPatternNode (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/converting-transformers/properties-extractors/AbstractPropertiesExtractor.ts:86:27)
    at t.isProhibitedPattern (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/converting-transformers/properties-extractors/AbstractPropertiesExtractor.ts:120:45)
    at t.extractPropertiesToExpressionStatements (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/converting-transformers/properties-extractors/AbstractPropertiesExtractor.ts:187:14)
    at transformObjectExpressionNode (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/converting-transformers/properties-extractors/VariableDeclaratorPropertiesExtractor.ts:42:21)
    at t.extract (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/converting-transformers/ObjectExpressionKeysTransformer.ts:104:36)
    at transformNode (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/converting-transformers/ObjectExpressionKeysTransformer.ts:67:33)
    at Controller.visitorFunction (/Users/vincent/dev/packager/node_modules/javascript-obfuscator/dist/webpack:/JavaScriptObfuscator/src/node-transformers/TransformersRunner.ts:111:55)
    at Controller.__execute (/Users/vincent/dev/packager/node_modules/estraverse/estraverse.js:397:31)
    at Controller.replace (/Users/vincent/dev/packager/node_modules/estraverse/estraverse.js:637:27)

Steps to Reproduce (for bugs)

create a file with the above code in a npm project
run the code
bug occurs

Your Environment

No related to environment, even on https://obfuscator.io/ it happens as well, the website does not obfuscate the code and displays TypeError: Cannot read property 'type' of undefined

Stack trace

See ‘Current Behavior’ section

Minimal working example that will help to reproduce issue

See code sample at top of bug report

Other notes

array spread operator like […arr1, …arr2] does not create this problem, only {…obj1, …obj2} does.

Issue Analytics

State:
Created 4 years ago
Comments:6 (4 by maintainers)

Top GitHub Comments

3reactions

zamotkincommented, Nov 20, 2019

The bug is fixed by PR above.

1reaction

sanex3339commented, Nov 20, 2019

Thank you! I will look into this tomorrow. Expect release with fix tomorrow.

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