Class MatListOptionHarness

src/material/list/testing/selection-list-harness.ts:79–157

/** Harness for interacting with a list option. */
export class MatListOptionHarness extends MatListItemHarnessBase {
  /** The selector for the host element of a `MatListOption` instance. */
  static hostSelector = '.mat-mdc-list-option';

  /**
   * Gets a `HarnessPredicate` that can be used to search for a list option with specific
   * attributes.
   * @param options Options for filtering which list option instances are considered a match.
   * @return a `HarnessPredicate` configured with the given options.
   */
  static with<T extends MatListOptionHarness>(
    this: ComponentHarnessConstructor<T>,
    options: ListOptionHarnessFilters = {},
  ): HarnessPredicate<T> {
    return getListItemPredicate(this, options).addOption(
      'is selected',
      options.selected,
      async (harness, selected) => (await harness.isSelected()) === selected,
    );
  }

  private _beforeCheckbox = this.locatorForOptional('.mdc-list-item__start .mdc-checkbox');
  private _beforeRadio = this.locatorForOptional('.mdc-list-item__start .mdc-radio');

  /** Gets the position of the checkbox relative to the list option content. */
  async getCheckboxPosition(): Promise<MatListOptionTogglePosition> {
    return (await this._beforeCheckbox()) !== null ? 'before' : 'after';
  }

  /** Gets the position of the radio relative to the list option content. */
  async getRadioPosition(): Promise<MatListOptionTogglePosition> {
    return (await this._beforeRadio()) !== null ? 'before' : 'after';
  }

  /** Whether the list option is selected. */
  async isSelected(): Promise<boolean> {
    return (await (await this.host()).getAttribute('aria-selected')) === 'true';
  }

  /** Focuses the list option. */
  async focus(): Promise<void> {
    return (await this.host()).focus();
  }

  /** Blurs the list option. */
  async blur(): Promise<void> {
    return (await this.host()).blur();
  }

  /** Whether the list option is focused. */
  async isFocused(): Promise<boolean> {
    return (await this.host()).isFocused();
  }

  /** Toggles the checked state of the checkbox. */
  async toggle() {
    return (await this.host()).click();
  }