npm WARN deprecated core-js@2.6.11: core-js@<3

问题:

I'm getting below error while creating a new Angular application -

npm WARN deprecated core-js@2.6.11: core-js@<3 is no longer maintained and not recommended for usage due to the number of issues. Please, upgrade your dependencies to the actual version of core-js@3.

I tried the solution given in below link but it did not work for me- Error: Please, upgrade your dependencies to the actual version of core-js@3

When I check version of Angular using 'ng --version' command, I see <error> as version for below listed packages -

@angular-devkit/architect    
@angular-devkit/core         
@angular-devkit/schematics   
@schematics/angular          
@schematics/update   

Could you please suggest what went wrong and what needs to be done to fix this?

P.S. - The same functionality was working fine a day before. And the already created projects are running fine locally.

回答1:

Indeed the issue was with cache. npm clean-install worked.

回答2:

It's a npm cache problem. Go to the path

C:\Users\johndoe\AppData\Roaming\npm-cache

and delete its content. Then open your console in administrator mode and execute the npm install command again

回答3:

Try:

npm cache clean --force
npm install -g @angular/cli@latest

回答4:

You should update the version of core-js to version above 3. npm install --save core-js@^3

You may also update the outdated packages using npm update [-g] [<pkg>...]

回答5:

I observed this warning message within a Vaadin project with Vaadin 14.1.3 after switching from dependency com.vaadin.vaadin to com.vaadin.vaadin-core. The warning was gone after these steps:

1. delete package-lock.json
2. execute mvn clean
3. execute mvn update

回答6:

So the issue is of version of the packages you have in your project.

Run command npm outdated inside your project directory. And see the difference between the Current And Wanted version of packages.

And then upgrade all package to match wanted version.