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recent Angular 4 makes it requiring some additional configuration to be added and some of the existing solutions are no longer valid due to changes in Angular.