Angular tests failing with Failed to execute ‘send’ on ‘XMLHttpRequest’
This is a problem of the new Angular Cli. Run your test with –sourcemaps=false and you will get the right error messages. See details here: https://github.com/angular/angular-cli/issues/7296 EDIT: Shorthand for this is: ng test -sm=false As of angular 6 the command is: ng test –source-map=false