Description
Command
build
Is this a regression?
- Yes, this behavior used to work in the previous version
The previous version in which this bug was not present was
No response
Description
I have a fresh Angular 19 application and I am trying to extend a browserslist configuration from a TS library that I changed to JS while debugging this issue. When I run the Angular build, it throws a type error.
Originally, I opened a ticket with the browserslist team so you can see browserslist/browserslist#891 for further context. I was getting errors with browserslist as they are using CommonJS requires in their code and my library and app were ESM. After removing browserslist-useragent-regexp, simplifying my library to JS, and still getting errors, they asked me to reach out to Angular as they were thinking Angular had an over complicated environment.
Minimal Reproduction
Create a shareable config following browserslist's instructions here: https://github.com/browserslist/browserslist?tab=readme-ov-file#shareable-configs
Here is my particular example with text changed as it's for a client I'm working with:
Snippet of application's package.json:
"type": "module",
"browserslist": [
"extends @scope/browserslist-config-xxxx"
]
Here is the library's code for this config:
index.js
const BROWSERSLIST_QUERY = ['defaults'];
export default BROWSERSLIST_QUERY;snippet of package.json
"type": "module",
"browserslist": [
"extends @scope/browserslist-config-xxxx"
]
Exception or Error
[error] TypeError: Cannot read properties of undefined (reading 'length')
at find (/../node_modules/browserslist/parse.js:12:25)
at matchBlock (/../node_modules/browserslist/parse.js:46:10)
at /../node_modules/browserslist/parse.js:73:17
at Array.map (<anonymous>)
at parse (/../node_modules/browserslist/parse.js:70:13)
at parseQueries (/../node_modules/browserslist/index.js:454:16)
at resolve (/../node_modules/browserslist/index.js:322:10)
at Function.select (/../node_modules/browserslist/index.js:1163:14)
at /../node_modules/browserslist/index.js:332:29
at Array.reduce (<anonymous>)
Your Environment
Angular CLI: 19.2.8
Node: 22.14.0
Package Manager: npm 10.9.2
OS: darwin arm64
Angular: 19.2.7
... common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router
Package Version
---------------------------------------------------------
@angular-devkit/architect 0.1902.8
@angular-devkit/build-angular 19.2.8
@angular-devkit/core 19.2.8
@angular-devkit/schematics 19.2.8
@angular/cli 19.2.8
@schematics/angular 19.2.8
rxjs 7.8.2
typescript 5.7.3
zone.js 0.15.0
Anything else relevant?
No response