Our team recently tried to upgrade to Angular 9 RC following the migration guide https://update.angular.io/ upgrading from 8.0x to 9.
When trying to run our universal build we are met with the following errors.
TypeError: Cannot Assign to read only property '_showWarnings' of object '#


Kindly provide the full output of ng version & also the output of the log file. Parts of it is truncated in the the screenshot.
Thanks.
I am facing the same issue . Here below is my ng version



I am using Angular 8 universal and facing the same problem.
Can you provide the output of npm ls webpack from within the project?
Hey @alan-agius4
@shane-arthur Did you solve this one?
This is the output of the log file.
TypeError: Cannot assign to read only property '_showWarnings' of object '#
@shane-arthur
Me and @kapilpatel20 are able to solve this issue.
The reason behind this is @angular-devkit/[email protected]
It was @angular-devkit/[email protected] when we created the Angular Universal project then someone did npm install and it got updated due to ^ symbol.
We reverted the version back to @angular-devkit/[email protected] and it started working properly.
i have the same problem... works but doesn't allow sequential or concurrent commands for practical builds
@shane-arthur
Me and @kapilpatel20 able to solve this issue.
The reason behind this is @angular-devkit/[email protected]
It was @angular-devkit/[email protected] when we created the Angular Universal project then someone did npm install and it got updated due to ^ symbol.
We the version back to @angular-devkit/[email protected] and it started working properly.
Great!!! thanks bro!
Replying "me too" except I am on [email protected] after installing a new app from Nx. This only occurs when I build my universal server. Downgrading to 0.803.5 works.
If it matters here are my dependencies, since I seem to be the outlier experiencing the error on 8 and not 9:
{
"@angular/common": "^8.2.0",
"@angular/compiler": "^8.2.0",
"@angular/core": "^8.2.0",
"@angular/platform-browser": "^8.2.0",
"@angular/platform-browser-dynamic": "^8.2.0",
"@angular/platform-server": "^8.2.14",
"@nguniversal/common": "^8.1.1",
"@nguniversal/express-engine": "^8.1.1",
"@nguniversal/module-map-ngfactory-loader": "^8.1.1",
}
We are experiencing the same issue in our team. Downgrading build-angular to 0.803.6 fixed our problem
With 0.803.7 up to the current version - which is 0.803.20 at the time of writing - we get the error, which has been reported in our Universal Builds
@shane-arthur
Me and @kapilpatel20 are able to solve this issue.
The reason behind this is @angular-devkit/[email protected]
It was @angular-devkit/[email protected] when we created the Angular Universal project then someone did npm install and it got updated due to ^ symbol.
We reverted the version back to @angular-devkit/[email protected] and it started working properly.
Thanks !
The only downside is that still you get some deps warnings with that version of @angular-devkit
Is this still reproducible? If so, can we please get a reproduction?
@shane-arthur
Me and @kapilpatel20 are able to solve this issue.
The reason behind this is @angular-devkit/[email protected]
It was @angular-devkit/[email protected] when we created the Angular Universal project then someone did npm install and it got updated due to ^ symbol.
We reverted the version back to @angular-devkit/[email protected] and it started working properly.
I have issue which solved from 0.803.7
so I can't back to 0.803.5
I change to "@angular-devkit/build-angular": "~0.800.0", and it work for me.
Hi all, is this still reproducible using Angular CLI latest version 9 or prerelease of 10?
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Most helpful comment
@shane-arthur
Me and @kapilpatel20 are able to solve this issue.
The reason behind this is @angular-devkit/[email protected]
It was @angular-devkit/[email protected] when we created the Angular Universal project then someone did npm install and it got updated due to ^ symbol.
We reverted the version back to @angular-devkit/[email protected] and it started working properly.