ERROR in Cannot use a JavaScript or TypeScript file for styleUrl or templateUrl.

[mgechev]

🐞 Bug report

Command (mark with an x)

• new
• build
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Is this a regression?

No

Description

When I change the templateUrl extension to .js or .ts, I'm getting:

ERROR in Cannot use a JavaScript or TypeScript file for styleUrl or templateUrl.

This doesn't provide enough context (e.g., where the error occurred).

🔬 Minimal Reproduction

Create a new project and update the extension of the templateUrl for AppComponent to .ts or .js.

🔥 Exception or Error

ERROR in Cannot use a JavaScript or TypeScript file for styleUrl or templateUrl.

🌍 Your Environment

v9.1

[BboyAkers]

Updated an angular 7 app to angular 9.1.9. Received this error. Any solutions or suggestions to better debug this? 🙂

[mgechev]

Make sure the styles and/or template you reference in your component have .css/.html extension.