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BrowserslistError: Unknown version 55 of and_chr

See original GitHub issue

The error occurs with the following custom usage data:

{
    "and_chr": {
        "55": 14.063696426229837
    }
}

& the following browserslist config in package.json:

{
  "browserslist": [
    "last 3 Chrome versions",
    "last 3 Firefox versions",
    "last 2 Safari versions",
    "last 3 Edge versions",
    "last 2 iOS versions",
    "last 2 Android versions",
    "last 2 ChromeAndroid versions",
    "IE >= 11",
    "> 0.2% in my stats"
  ]
}

Right now a temporary fix is setting the version key to 0 instead of 55, otherwise this error is thrown:

BrowserslistError: Unknown version 55 of and_chr
    at error (/Users/beneb/projects/mergerules-bug-test/node_modules/browserslist/index.js:37:11)
    at Function.select (/Users/beneb/projects/mergerules-bug-test/node_modules/browserslist/index.js:603:21)
    at /Users/beneb/projects/mergerules-bug-test/node_modules/browserslist/index.js:207:41
    at Array.forEach (native)
    at browserslist (/Users/beneb/projects/mergerules-bug-test/node_modules/browserslist/index.js:196:13)

Thanks to @notacouch for providing a test case which reproduces the error! 💯

https://github.com/notacouch/mergerules-bug-test/commit/4d7b1be44aa75683851beec8169a3fc02cdb0361