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[@rollup/plugin-commonjs] engine-v8-version.js:25 Uncaught TypeError: userAgent.match is not a function at engine-v8-version.js:25:21 in core-js

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
javascript, rollup
Domain
build-system

Research direction

Start with the linked reproduction, run npm start, and navigate to http://localhost:8000/dummy. Inspect node_modules/core-js/internals/engine-v8-version.js at line 25 and trace the userAgent value when @rollup/plugin-commonjs compiles the core-js UMD module. Done means the browser no longer reports the TypeError.

Written by the indexing model from the issue text.

Description

c⁴ ⋅ need more info
Expected Behavior

Run npm start and navigate to http://localhost:8000/dummy. plugin-commonjs 'compiles' https://github.com/zloirock/core-js UMD module into es6.

Actual Behavior

google-chrome reports following in console:

Uncaught TypeError: userAgent.match is not a function
    at engine-v8-version.js:25:21

in /node_modules/core-js/internals/engine-v8-version.js

Additional Information
Dominant language
JavaScript
Stars
3.8k
Forks
635
PR merge metrics
No merged PRs in 30d

Contributor guide

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  4. Open a pull request that references the issue number.

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