Material Angular 6 DatePicker在前一天解析我的日期

当前版本的Material Angular DatePicker发生了一些非常奇怪的事情,在我将它从A5更新到A6之后,它开始在1天之前解析我的日期,示例在这里： https://stackblitz.com/edit/angular6-datepicker-parsing-wrong-date

我正在使用原始文档示例,对我自己的语言稍有改变语言,并将自定义日期值应用于ngModel,以便它可以解析.

但你可以在这里查看代码：

import {Component} from '@angular/core';
import {MAT_MOMENT_DATE_FORMATS,MomentDateAdapter} from '@angular/material-moment-adapter';
import {DateAdapter,MAT_DATE_FORMATS,MAT_DATE_LOCALE} from '@angular/material/core';

@Component({
  selector: 'datepicker-locale-example',templateUrl: 'datepicker-locale-example.html',styleUrls: ['datepicker-locale-example.css'],providers: [
    {provide: MAT_DATE_LOCALE,useValue: 'pt'},//my change from the original documentation example
    {provide: DateAdapter,useClass: MomentDateAdapter,deps: [MAT_DATE_LOCALE]},{provide: MAT_DATE_FORMATS,useValue: MAT_MOMENT_DATE_FORMATS},],})
export class DatepickerLocaleExample {
  constructor(private adapter: DateAdapter<any>) {}

  private someDate = '2018-01-31'; //my change from the original documentation example

  french() {
    this.adapter.setLocale('fr');
  }
}

HTML：

<mat-form-field>
  <input matInput [matDatepicker]="myDatePicker" placeholder="Different locale" [(ngModel)]="someDate"> <!-- my change from the original documentation example -->
  <mat-datepicker-toggle matSuffix [for]="myDatePicker"></mat-datepicker-toggle>
  <mat-datepicker #myDatePicker></mat-datepicker>
  <mat-hint>Actual Date: {{someDate}}</mat-hint>
</mat-form-field>

<button mat-button (click)="french()">Dynamically switch to French</button>

有谁知道如何解决这个问题？