Missing locale info for Kendo Intl Service when testing with Jest in Angular 7

I had multiple tests for a very specific numeric component that handles locale formatting. The tests were fine with Karma, but once we changed it to Jest this error started to appear:

NoLocale: Missing locale info for 'de-DE' Solution: http://www.telerik.com/kendo-angular-ui/components/internationalization/troubleshooting/#toc-no-locale

The IntlService is initialized with en-US locale id, so I changed it for each test, depending the format that I wanted to assert (de-DE or en-GB).

These are the test examples in the component.spec.ts:

numeric-textbox.component.spec.ts

import { async, ComponentFixture, TestBed } from '@angular/core/testing';
import { NumericTextBoxComponent } from './numeric-textbox.component';
import { FormsModule } from '@angular/forms';
import { CldrIntlService, IntlModule, load } from '@progress/kendo-angular-intl';

describe('NumericTextBoxComponent', () => {
  let component: NumericTextBoxComponent;
  let fixture: ComponentFixture<NumericTextBoxComponent>;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [ FormsModule, IntlModule ],
      declarations: [ NumericTextBoxComponent ],
    })
    .compileComponents();
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(NumericTextBoxComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });

  it('should create', () => {
    expect(component).toBeTruthy();
  });

  it('User writes valid numbers with German/International notation', () => {
    component.format = 'n2';
    (<CldrIntlService>component.intlService).localeId = 'de-DE';
    fixture.detectChanges();
    fixture.whenStable().then(() => {
      const displayValueInput: HTMLInputElement = fixture.debugElement.nativeElement.querySelector('input');

  // absolute integer
  displayValueInput.value = '123456789';
  displayValueInput.dispatchEvent(new Event('input'));
  displayValueInput.dispatchEvent(new Event('focusout'));
  expect(component.inputValue).toBe('123456789');
  expect(component.displayValue).toBe('123.456.789,00');
  });
});

it('displays the correct format when the control is created in english context', () => {
    component.format = 'n2';
    (<CldrIntlService>component.intlService).localeId = 'en-GB';
    fixture.detectChanges();
    fixture.whenStable().then(() => {
      const displayValueInput: HTMLInputElement = fixture.debugElement.nativeElement.querySelector('input');
      displayValueInput.value = '123456789.12';
      displayValueInput.dispatchEvent(new Event('input'));
      displayValueInput.dispatchEvent(new Event('focusout'));
      expect(component.inputValue).toBe('123456789.12');
      expect(component.displayValue).toBe('123,456,789.12');
    });
  });

The rare thing is 'en-GB' locale is recognised by the Intl Service (so the test is running fine), but 'de-DE' is not.

My question is: How do I import the de-DE locale information to the test environment, so that it can be recognised by the Intl Service dynamically?

---

As an additional information, the focusout event triggers the following method in the component:

numeric-textbox.component.ts

onFocusOut(first: boolean = false): void {
      console.log("onFocusOut");
        if (this.isReadOnly && !first && !this.isFocusIn) { return; }
        this.isFocusIn = false;
        // save the temporal the editable display value into the inputValue.
        // if the escape key was pressed, then we undo the actual displayValue to the lastInputValue.
        this.inputValue = !this.wasEscapePressed ? this.displayValue : this.lastInputValue;
        this.wasEscapePressed = false;
        // update the readable display value with the absolute value of the input value (or zero if it is null, zero or empty).
        this.displayValue = this.formatDisplayValue(this.inputValue);
    }

formatDisplayValue(input: string): string {
        // single signs, nulls, empty and zeros are shown as zero
        if (this.checkNullZeroOrEmpty(input) || this.isSignOnly(input)) {
            input = NumericTextBoxComponent.ZERO;
        } else if (this.IsPositiveValue(input) && input[0] === NumericTextBoxComponent.PLUS_SIGN) {
            // positive signs at the beginning are trim
            input = input.replace(NumericTextBoxComponent.PLUS_SIGN, '');
        }

        // display value are always the absolute value
        const numberValue = Math.abs(this.getNumberValue(input));

        // finally return the number formatted based in the locale. 
        return this.intlService.formatNumber(numberValue, this.format);
    }

So, when I made focus out of the input HTML element, the display value is formatted depending the locale.

from Missing locale info for Kendo Intl Service when testing with Jest in Angular 7