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AssignmentRestProperty does not work without AssignmentPropertyList

See original GitHub issue

I’ve created an issue as a bug as partial ECMAScript 2019 support is declared on web site.

Expected Behavior

const { ...fields } = req.body; should be obfuscated

Current Behavior

For now seems like many features of ECMAScript 2018 is supported except at least one when AssignmentRestProperty alone is used at the LeftHandSideExpression of destructuring assignment. Example: const { ...fields } = req.body; Runing javascript-obfuscator against that string gives:

[javascript-obfuscator-cli] Error in file: playground/test.js...

Although it works well when AssignmentPropertyList is present before the rest. This string will not cause an error: const { foo, ...fields } = req.body;

Steps to Reproduce

create test.js file with a content from example below
run javascript-obfuscator against it javascript-obfuscator ./test.js --output ./
experience an error

Your Environment

Obfuscator version used: 0.28.1
Node version used: 12.13.1

Stack trace

/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:2226
                if (property.value.type !== Syntax.Identifier) {
                                   ^
TypeError: Cannot read property 'type' of undefined
    at CodeGenerator.ObjectPattern (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:2226:36)
    at CodeGenerator.generateExpression (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:2469:28)
    at CodeGenerator.VariableDeclarator (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:1438:26)
    at CodeGenerator.generateStatement (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:2482:33)
    at block (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:1465:38)
    at CodeGenerator.VariableDeclaration (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:1483:17)
    at CodeGenerator.generateStatement (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:2482:33)
    at /Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:1075:51
    at withIndent (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:576:9)
    at CodeGenerator.BlockStatement (/Users/lonedone/.nvm/versions/node/v12.13.1/lib/node_modules/javascript-obfuscator/node_modules/escodegen/escodegen.js:1025:13)

Minimal working example that will help to reproduce issue

const req = {
  foo: 'foo_str',
  bar: 'bar_str',
};

const { ...fields } = req;
console.log(fields);

Issue Analytics

State:
Created 3 years ago
Reactions:2
Comments:5 (4 by maintainers)

Top GitHub Comments

4reactions

sanex3339commented, May 30, 2020

I created PR with fix some time ago. Please ping this PR https://github.com/estools/escodegen/pull/408

1reaction

sanex3339commented, Jun 4, 2020

Fixed and released as 0.28.5

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