removed unused variable and cause syntax error of bind function

[arthurlz]

• Rollup Version: 2.83.3
• Operating System (or Browser): Mac Chrome
• Node Version (if applicable): 14.53
• Link to reproduction (IMPORTANT, read below): https://repl.it/@loveppears/rollup-repro-1

I am building a js library which requires a 3rd library lottie, and it has the following code

var wiggle = function wiggle(){}.bind(this)

But after I import it and build it, I got error in the line below

function wiggle(){}.bind(this)

uncaught syntaxerror unexpected identifier '.'

download the zip from repl and build it then open the dist/index.html , you could find this error.

Could you please tell me how can I avoid this

Expected Behavior

var wiggle = function wiggle(){}.bind(this)

Actual Behavior

function wiggle(){}.bind(this)

[kzc]

Same issue with object literals:

$ rollup -v
rollup v2.38.4

$ echo 'var x = {log: console.log}.log(123);' | rollup --silent | node
[stdin]:1
{log: console.log}.log(123);
                  ^
SyntaxError: Unexpected token '.'

[kzc]

and classes:

$ echo 'var a = class C{ static f(x){console.log(x)} }.f(123);' | rollup --silent | node
[stdin]:1
class C{ static f(x){console.log(x);} }.f(123);
                                       ^
SyntaxError: Unexpected token '.'

[lukastaegert]

Yes, I noticed. Working on a fix but might take a day.

[matthewp]

Introduced in this change: #3933

[lukastaegert]

Fix at #3951