angular/devtools/projects/ng-devtools-backend/src/lib/highlighter.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.io/license
 */

import * as highlighter from './highlighter';

describe('highlighter', () => {
  describe('findComponentAndHost', () => {
    it('should return undefined when no node is provided', () => {
      expect(highlighter.findComponentAndHost(undefined)).toEqual({component: null, host: null});
    });

    it('should return same component and host if component exists', () => {
      (window as any).ng = {
        getComponent: (el: any) => el,
      };
      const element = document.createElement('div');
      const data = highlighter.findComponentAndHost(element as any);
      expect(data.component).toBeTruthy();
      expect(data.host).toBeTruthy();
      expect(data.component).toEqual(data.host);
    });

    it('should return null component and host if component do not exists', () => {
      (window as any).ng = {
        getComponent: () => undefined,
      };
      const element = document.createElement('div');
      const data = highlighter.findComponentAndHost(element as any);
      expect(data.component).toBeFalsy();
      expect(data.host).toBeFalsy();
    });
  });

  describe('getComponentName', () => {
    it('should return null when called with null values', () => {
      let name = highlighter.getDirectiveName(null);
      expect(name).toBe('unknown');

      name = highlighter.getDirectiveName(undefined);
      expect(name).toBe('unknown');
    });

    it('should return correct component name', () => {
      const MOCK_COMPONENT = {
        constructor: {
          name: 'mock-component',
        },
      };

      const name = highlighter.getDirectiveName(MOCK_COMPONENT as any);
      expect(name).toBe(MOCK_COMPONENT.constructor.name);
    });
  });

  describe('inDoc', () => {
    it('should return false if no node is provided', () => {
      expect(highlighter.inDoc(undefined)).toBeFalsy();
    });

    it('should be true if doc and node are equal', () => {
      const node = {
        parentNode: {},
        ownerDocument: {
          documentElement: {},
        },
      };

      node.ownerDocument.documentElement = node;
      expect(highlighter.inDoc(node)).toBeTruthy();
    });

    it('should be true if doc and parent are equal', () => {
      const node = {
        parentNode: 'node',
        ownerDocument: {
          documentElement: 'node',
        },
      };

      expect(highlighter.inDoc(node)).toBeTruthy();
    });

    it('should be true if doc contains parent', () => {
      const node = {
        parentNode: {
          nodeType: 1,
        },
        ownerDocument: {
          documentElement: {
            contains: () => true,
          },
        },
      };
      expect(highlighter.inDoc(node)).toBeTruthy();
    });
  });

  describe('highlightHydrationElement', () => {
    afterEach(() => {
      document.body.innerHTML = '';
      delete (window as any).ng;
    });

    it('should show hydration overlay with svg', () => {
      const appNode = document.createElement('app');
      appNode.style.width = '500px';
      appNode.style.height = '400px';
      appNode.style.display = 'block';
      document.body.appendChild(appNode);
      (window as any).ng = {
        getComponent: (el: any) => el,
      };

      highlighter.highlightHydrationElement(appNode, {status: 'hydrated'});

      expect(document.body.querySelectorAll('div').length).toBe(2);
      expect(document.body.querySelectorAll('svg').length).toBe(1);

      const overlay = document.body.querySelector('.ng-devtools-overlay');
      expect(overlay?.getBoundingClientRect().width).toBe(500);
      expect(overlay?.getBoundingClientRect().height).toBe(400);

      highlighter.removeHydrationHighlights();
      expect(document.body.querySelectorAll('div').length).toBe(0);
      expect(document.body.querySelectorAll('svg').length).toBe(0);
    });

    it('should show hydration overlay without svg (too small)', () => {
      const appNode = document.createElement('app');
      appNode.style.width = '25px';
      appNode.style.height = '20px';
      appNode.style.display = 'block';
      document.body.appendChild(appNode);
      (window as any).ng = {
        getComponent: (el: any) => el,
      };

      highlighter.highlightHydrationElement(appNode, {status: 'hydrated'});

      expect(document.body.querySelectorAll('div').length).toBe(1);
      expect(document.body.querySelectorAll('svg').length).toBe(0);

      const overlay = document.body.querySelector('.ng-devtools-overlay');
      expect(overlay?.getBoundingClientRect().width).toBe(25);
      expect(overlay?.getBoundingClientRect().height).toBe(20);

      highlighter.removeHydrationHighlights();
      expect(document.body.querySelectorAll('div').length).toBe(0);
      expect(document.body.querySelectorAll('svg').length).toBe(0);
    });

    it('should show hydration overlay and selected component overlay at the same time ', () => {
      const appNode = document.createElement('app');
      appNode.style.width = '25px';
      appNode.style.height = '20px';
      appNode.style.display = 'block';
      document.body.appendChild(appNode);
      (window as any).ng = {
        getComponent: (el: any) => el,
      };

      highlighter.highlightHydrationElement(appNode, {status: 'hydrated'});
      highlighter.highlightSelectedElement(appNode);

      expect(document.body.querySelectorAll('.ng-devtools-overlay').length).toBe(2);
      highlighter.removeHydrationHighlights();
      expect(document.body.querySelectorAll('.ng-devtools-overlay').length).toBe(1);
      highlighter.unHighlight();
      expect(document.body.querySelectorAll('.ng-devtools-overlay').length).toBe(0);

      highlighter.highlightHydrationElement(appNode, {status: 'hydrated'});
      highlighter.highlightSelectedElement(appNode);
      highlighter.unHighlight();
      expect(document.body.querySelectorAll('.ng-devtools-overlay').length).toBe(1);
      highlighter.removeHydrationHighlights();
      expect(document.body.querySelectorAll('.ng-devtools-overlay').length).toBe(0);
    });
  });

  describe('highlightSelectedElement', () => {
    it('should show overlay', () => {
      const appNode = document.createElement('app');
      appNode.style.width = '25px';
      appNode.style.height = '20px';
      appNode.style.display = 'block';
      document.body.appendChild(appNode);
      (window as any).ng = {
        getComponent: (el: any) => new (class FakeComponent {})(),
      };

      highlighter.highlightSelectedElement(appNode);

      const overlay = document.body.querySelectorAll('.ng-devtools-overlay');
      expect(overlay.length).toBe(1);
      expect(overlay[0].innerHTML).toContain('FakeComponent');

      highlighter.unHighlight();
      expect(document.body.querySelectorAll('.ng-devtools-overlay').length).toBe(0);
    });
  });
});