Angular 9->10 migration. TypeError: core_1.virtualFs.createSyncHost is not a function

Question

After ng upgrade serve runs into an error:

TypeError: core_1.virtualFs.createSyncHost is not a function

any ideas of how to fix it?

Answer 1

I had the exact same error after upgrading. Removing the node_modules and re-installing the dependencies fixed the problem:

# with yarn
rm -rf node_modules && yarn 

# with npm
rm -rf node_modules && npm install