Incorrect Minification Result for Destructuring Assignment with Spread Operator

[experdot]

Description:

When using NUglify to minify JavaScript code that contains a destructuring assignment with a spread operator, the resulting minified code is incorrect. Specifically, the variable names in the destructuring assignment are being incorrectly renamed, leading to potential runtime errors.

Steps to Reproduce:

1. Use the following input code:

   $m=(e,t,n,o,r,s)=>{const{uid:a=t,...i}=n;}

2. Run the following C# code to minify the JavaScript:

   var result = NUglify.Uglify.Js("$m=(e,t,n,o,r,s)=>{const{uid:a=t,...i}=n;}").Code;
   Console.WriteLine(result);

3. Observe the output:

   $m=(n,t,i)=>{const{uid:r=t,...i}=i}

Actual Behavior:

The minified code incorrectly renames variables in the destructuring assignment, leading to a broken structure:

$m=(n,t,i)=>{const{uid:r=t,...i}=i}

Here, the variable i is reused both as the object being destructured and as the rest parameter, which is invalid and will cause runtime errors.

Environment:

• NUglify Version: 1.21.13

Additional Notes:

This issue seems to occur specifically when destructuring assignments involve a default value (uid:a=t) and a spread operator (...i). It appears that the variable renaming logic in NUglify is not handling these cases correctly.

[trullock]

Sounds likely, there were similar bugs in the same area