Function parameters ending with ${int} in source aren't escaped, and shadow higher scoped generated variables

[bloodyowl]

Context:
BuckleScript generates variables like name$1.

• Rollup Version: v1.1.2
• Operating System (or Browser): All
• Node Version: v10.14.2

How Do We Reproduce?

Input

// main.js
import {x} from "./maths.js";

console.log(x(value));

// maths.js
var value = "1";

export function x(value$1) { return value$1 + value } 

Expected Behavior

var value$1 = "1";

function x(value$1$1) { return value$1$1 + value$1 }

console.log(x(value));

or

var value$1 = "1";

function x(value_$_1) { return value_$_1 + value$1 }

console.log(x(value));

Actual Behavior

var value$1 = "1";

function x(value$1) { return value$1 + value$1 }

console.log(x(value));

https://rollupjs.org/repl?version=1.1.2&shareable=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

[lukastaegert]

Thanks, the deconflicting logic rewrite I am currently working on should be able to handle this, will definitely include your test case!

[lukastaegert]

Fix a #2689