No value accessor while trying to test basic form with angular 4 and ionic 3

Question

I have a simple ionic form:

<ion-header>
    <ion-navbar>
        <ion-title>Foo</ion-title>
    </ion-navbar>
</ion-header>

<ion-content padding>
    <form [formGroup]="fooForm">
        <ion-item>
            <ion-label floating>Name</ion-label>
            <ion-input formControlName="name" type="text"></ion-input>
        </ion-item>
    </form>
    <button ion-button full color="primary" (click)="save()">Save</button>
</ion-content>

and a page component:

import { Component } from '@angular/core';
import { FormBuilder, FormGroup } from '@angular/forms';

@Component({
    selector: 'fo-page-foo',
    templateUrl: './foo.html'
})
export class FooPage {
    fooForm: FormGroup;

    constructor(public formBuilder: FormBuilder) {
    }

    ngOnInit() {
        this.fooForm = this.formBuilder.group({
            name: ['']
        });

    }

    public save() {
        console.log(this.fooForm.value);
    }
}

and a test:

import { FooPage } from './foo';
import { TestBed, ComponentFixture } from '@angular/core/testing';
import { CUSTOM_ELEMENTS_SCHEMA, DebugElement } from '@angular/core';
import { FormsModule, ReactiveFormsModule } from "@angular/forms";
import { Form } from 'ionic-angular';

describe('Foo Page:', () => {

    let comp: FooPage;
    let fixture: ComponentFixture<FooPage>;
    let de: DebugElement;

    beforeEach(() => {
        TestBed.configureTestingModule({
            schemas: [CUSTOM_ELEMENTS_SCHEMA],
            declarations: [FooPage],
            providers: [Form],
            imports: [FormsModule, ReactiveFormsModule],
        });
        fixture = TestBed.createComponent(FooPage);
        fixture.detectChanges();
        comp = fixture.componentInstance;
        de = fixture.debugElement;
        comp.ngOnInit();
    });

    describe('.constructor()', () => {
        it('Should be defined', () => {
            expect(comp).toBeDefined();
        });
    });
});

project and test structure is based on https://github.com/marcoturi/ionic-boilerplate. The test fails due to error: No value accessor for form control.

I was trying various approaches yet it seems that combination of Ionic specifics and recent Angular 4 makes it requiring some additional configuration to be added and some of the existing solutions are no longer valid due to changes in Angular.

Answer 1

I hit this problem two days ago and thanks to isolating it to post on SO was able to get to the solution base on slightly similar question

Main point is to add IonicModule to imports yet this triggers bunch of other Ionic imports:

import {
    App, Platform, Config, Keyboard,
    Form, IonicModule, DomController
} from 'ionic-angular';
import { 
    mockConfig, mockDomController, MockPlatform, mockPlatform 
} from 'ionic-angular/util/mock-providers';

and so updated beforeEach should start with

    TestBed.configureTestingModule({
        schemas: [CUSTOM_ELEMENTS_SCHEMA],
        declarations: [FooPage],
        providers: [
            App,
            Form,
            Keyboard,
            { provide: Platform, useClass: MockPlatform },
            { provide: DomController, useValue: mockDomController(mockPlatform()) },
            { provide: Config, useValue: mockConfig() },
        ],
        imports: [
            FormsModule,
            IonicModule,
            ReactiveFormsModule
        ],
    });

PR with the above example got already merged to https://github.com/marcoturi/ionic-boilerplate.