Angular 9 - NGCC fails with an unhandled exception

Question

Buidling the application after having upgraded dependcies to Angular 9 (and having performed necessary code changes) throws an error:

Compiling @ang

Answer 1

• I removed tslib.js from package.json
• Removed package-lock.json
• Deleted node_modules folder
• npm i
• ng serve

Worked for me

Answer 2

In my particular case the @angular-devkit/build-angular was updated to "^0.1001.2" in my package.json after running the npm audit fix. (This version seems to belong to angular 10, instead of the local projects' angular version (v9.1.7))

After reverting this change, everything started working again :

"@angular-devkit/build-angular": "~0.901.6"

Answer 3

Well in my case I was trying to run an angular project of an older version with a newer version of node. I did this:

Removes all the existing nodule modules.

rm -rf node_modules

update node js to latest

npm update
npm install

updates the angular project version to the latest

ng update @angular/core

updates the project cli to the latest

ng update @angular/cli

Now start the project

ng-serve

Answer 4

I had to go into my tsconfig.spec.json file and add

"angularCompilerOptions": {
    "enableIvy": false
}

It was already in my tsconfig.json file.

Answer 5

Using terminal/cmd,

1st Step: ng update @angular/cli @angular/core

2nd Step: ng update

3rd Step: ng serve

Fixed mine.

NOTE Your custom css files in bootstrap folder might get deleted. Back them up before and place them back after the update!

Answer 6

Try to remove the node_modules folder and run install again:

rm -rf node_modules

npm install

For me it has solved the problem.