angular/packages/elements/test/extract-projectable-nodes_spec.ts

/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.dev/license
 */

import {extractProjectableNodes} from '../src/extract-projectable-nodes';

describe('extractProjectableNodes()', () => {
  let elem: HTMLElement;
  let childNodes: ChildNode[];

  const expectProjectableNodes = (matches: {[selector: string]: number[]}) => {
    const selectors = Object.keys(matches);
    const expected = selectors.map((selector) => {
      const matchingIndices = matches[selector];
      return matchingIndices.map((idx) => childNodes[idx]);
    });

    expect(extractProjectableNodes(elem, selectors)).toEqual(expected);
  };
  const test = (matches: {[selector: string]: number[]}) => () => expectProjectableNodes(matches);

  beforeEach(() => {
    elem = document.createElement('div');
    elem.innerHTML =
      '<div class="foo" first="">' +
      '<span class="bar"></span>' +
      '</div>' +
      '<span id="bar"></span>' +
      '<!-- Comment -->' +
      'Text' +
      '<blink class="foo" id="quux"></blink>' +
      'More text';
    childNodes = Array.prototype.slice.call(elem.childNodes);
  });

  it(
    'should match each node to the corresponding selector',
    test({
      '[first]': [0],
      '#bar': [1],
      '#quux': [4],
    }),
  );

  it(
    'should ignore non-matching nodes',
    test({
      '.zoo': [],
    }),
  );

  it(
    'should only match top-level child nodes',
    test({
      'span': [1],
      '.bar': [],
    }),
  );

  it(
    'should support complex selectors',
    test({
      '.foo:not(div)': [4],
      'div + #bar': [1],
    }),
  );

  it(
    'should match each node with the first matching selector',
    test({
      'div': [0],
      '.foo': [4],
      'blink': [],
    }),
  );

  describe('(with wildcard selector)', () => {
    it(
      'should match non-element nodes to `*` (but still ignore comments)',
      test({
        'div,span,blink': [0, 1, 4],
        '*': [2, 3, 5],
      }),
    );

    it(
      'should match otherwise unmatched nodes to `*`',
      test({
        'div,blink': [0, 4],
        '*': [1, 2, 3, 5],
      }),
    );

    it(
      'should give higher priority to `*` (eve if it appears first)',
      test({
        '*': [2, 3, 5],
        'div,span,blink': [0, 1, 4],
      }),
    );
  });
});