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Broken build due to mangled dependency props

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#819 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
javascript
Domain
build-system

Research direction

Start by reproducing the default and UMD builds with the shown named import and mangle regex, then compare their generated require calls with mangling disabled. Done means calls to the dependency's _fn export remain valid in both builds while local names can still be mangled.

Written by the indexing model from the issue text.

Description

I have some code that imports a named export of a dependency as follows:

import { _fn } from '@x/y';
...
_fn(...); // calling _fn

With mangle configured with "regex": "^_[^_]", the default build (index.js) transpiles this to:

const z = require('@x/y');
...
z.a(...); // calling _fn???

Disabling mangling works as expected:

const z = require('@x/y');
...
z._fn(...); // calling _fn

There is a similar problem with the umd build.

Any way around this?

Dominant language
JavaScript
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  4. Open a pull request that references the issue number.

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