I'm getting these warnings after ng build (Angular 12):
./node_modules/@angular/core/__ivy_ngcc__/fesm2015/core.js:35289:13-34 - Warning: Critical dependency: the request of a dependency is an expression
./node_modules/@angular/core/__ivy_ngcc__/fesm2015/core.js:35301:13-100 - Warning: Critical dependency: the request of a dependency is an expression
I'm using @angular-builders/custom-webpack to extract the moment.js from the initial bundle.
If I disabled the @angular-builders/custom-webpack, then everything goes well and the warnings disappear.
Also, the warnings disappeared if I add the following within custom-webpack.config.js:
new webpack.ContextReplacementPlugin(
/\@angular(\\|\/)core(\\|\/)__ivy_ngcc__(\\|\/)fesm2015/,
path.join(__dirname, './src'),
{}
),
So kindly, what causing these warnings exactly? and is there any other solution to handle it without adding the plugin to the webpack config like above? Thanks.
I got the following feedback from the Angular dev team:
This comes from code in the deprecated SystemJsNgModuleLoader and is normally suppressed when using the CLI builders, which also uses ContextReplacementPlugin. I don't think there is an alternative to suppress them, other than to not suppress them and ignore the warnings.
https://github.com/angular/angular/issues/43092#issuecomment-895848535
So I ended up using the mentioned CLI builders code as the following within custom-webpack.config.js:
// Always replace the context for the System.import in angular/core to prevent warnings.
new ContextReplacementPlugin(
/\@angular(\\|\/)core(\\|\/)/,
path.join(__dirname, '$_lazy_route_resources'),
{}
),
When using a custom ContextReplacementPlugin in Angular 12, take care about this:
If in your custom configuration you specify a plugin that is already added by Angular CLI then by default the two instances will be merged.
I use the ContextReplacementPlugin to exclude moment.js locales. After upgrading to Angular 12, all locales were removed, because it's config was merged with $_lazy_route_resources. I solved it by setting replaceDuplicatePlugins to true.