puppeteer/test/src/queryselector.spec.ts

/**
 * @license
 * Copyright 2018 Google Inc.
 * SPDX-License-Identifier: Apache-2.0
 */
import expect from 'expect';
import {Puppeteer} from 'puppeteer';
import type {CustomQueryHandler} from 'puppeteer-core/internal/common/CustomQueryHandler.js';

import {getTestState, setupTestBrowserHooks} from './mocha-utils.js';

describe('querySelector', function () {
  setupTestBrowserHooks();

  describe('Page.$eval', function () {
    it('should work', async () => {
      const {page} = await getTestState();

      await page.setContent('<section id="testAttribute">43543</section>');
      const idAttribute = await page.$eval('section', e => {
        return e.id;
      });
      expect(idAttribute).toBe('testAttribute');
    });
    it('should accept arguments', async () => {
      const {page} = await getTestState();

      await page.setContent('<section>hello</section>');
      const text = await page.$eval(
        'section',
        (e, suffix) => {
          return e.textContent! + suffix;
        },
        ' world!'
      );
      expect(text).toBe('hello world!');
    });
    it('should accept ElementHandles as arguments', async () => {
      const {page} = await getTestState();

      await page.setContent('<section>hello</section><div> world</div>');
      using divHandle = (await page.$('div'))!;
      const text = await page.$eval(
        'section',
        (e, div) => {
          return e.textContent! + (div as HTMLElement).textContent!;
        },
        divHandle
      );
      expect(text).toBe('hello world');
    });
    it('should throw error if no element is found', async () => {
      const {page} = await getTestState();

      let error!: Error;
      await page
        .$eval('section', e => {
          return e.id;
        })
        .catch(error_ => {
          return (error = error_);
        });
      expect(error.message).toContain(
        'failed to find element matching selector "section"'
      );
    });
  });

  // The tests for $$eval are repeated later in this file in the test group 'QueryAll'.
  // This is done to also test a query handler where QueryAll returns an Element[]
  // as opposed to NodeListOf<Element>.
  describe('Page.$$eval', function () {
    it('should work', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<div>hello</div><div>beautiful</div><div>world!</div>'
      );
      const divsCount = await page.$$eval('div', divs => {
        return divs.length;
      });
      expect(divsCount).toBe(3);
    });
    it('should accept extra arguments', async () => {
      const {page} = await getTestState();
      await page.setContent(
        '<div>hello</div><div>beautiful</div><div>world!</div>'
      );
      const divsCountPlus5 = await page.$$eval(
        'div',
        (divs, two, three) => {
          return divs.length + (two as number) + (three as number);
        },
        2,
        3
      );
      expect(divsCountPlus5).toBe(8);
    });
    it('should accept ElementHandles as arguments', async () => {
      const {page} = await getTestState();
      await page.setContent(
        '<section>2</section><section>2</section><section>1</section><div>3</div>'
      );
      using divHandle = (await page.$('div'))!;
      const sum = await page.$$eval(
        'section',
        (sections, div) => {
          return (
            sections.reduce((acc, section) => {
              return acc + Number(section.textContent);
            }, 0) + Number((div as HTMLElement).textContent)
          );
        },
        divHandle
      );
      expect(sum).toBe(8);
    });
    it('should handle many elements', async function () {
      this.timeout(25_000);

      const {page} = await getTestState();
      await page.evaluate(
        `
        for (var i = 0; i <= 1000; i++) {
            const section = document.createElement('section');
            section.textContent = i;
            document.body.appendChild(section);
        }
        `
      );
      const sum = await page.$$eval('section', sections => {
        return sections.reduce((acc, section) => {
          return acc + Number(section.textContent);
        }, 0);
      });
      expect(sum).toBe(500500);
    });
  });

  describe('Page.$', function () {
    it('should query existing element', async () => {
      const {page} = await getTestState();

      await page.setContent('<section>test</section>');
      using element = (await page.$('section'))!;
      expect(element).toBeTruthy();
    });
    it('should return null for non-existing element', async () => {
      const {page} = await getTestState();

      using element = (await page.$('non-existing-element'))!;
      expect(element).toBe(null);
    });
  });

  describe('Page.$$', function () {
    it('should query existing elements', async () => {
      const {page} = await getTestState();

      await page.setContent('<div>A</div><br/><div>B</div>');
      const elements = await page.$$('div');
      expect(elements).toHaveLength(2);
      const promises = elements.map(element => {
        return page.evaluate((e: HTMLElement) => {
          return e.textContent;
        }, element);
      });
      expect(await Promise.all(promises)).toEqual(['A', 'B']);
    });
    it('should return empty array if nothing is found', async () => {
      const {page, server} = await getTestState();

      await page.goto(server.EMPTY_PAGE);
      const elements = await page.$$('div');
      expect(elements).toHaveLength(0);
    });
  });

  describe('Page.$x', function () {
    it('should query existing element', async () => {
      const {page} = await getTestState();

      await page.setContent('<section>test</section>');
      const elements = await page.$x('/html/body/section');
      expect(elements[0]).toBeTruthy();
      expect(elements).toHaveLength(1);
    });
    it('should return empty array for non-existing element', async () => {
      const {page} = await getTestState();

      const element = await page.$x('/html/body/non-existing-element');
      expect(element).toEqual([]);
    });
    it('should return multiple elements', async () => {
      const {page} = await getTestState();

      await page.setContent('<div></div><div></div>');
      const elements = await page.$x('/html/body/div');
      expect(elements).toHaveLength(2);
    });
  });

  describe('ElementHandle.$', function () {
    it('should query existing element', async () => {
      const {page, server} = await getTestState();

      await page.goto(server.PREFIX + '/playground.html');
      await page.setContent(
        '<html><body><div class="second"><div class="inner">A</div></div></body></html>'
      );
      using html = (await page.$('html'))!;
      using second = (await html.$('.second'))!;
      using inner = await second.$('.inner');
      const content = await page.evaluate(e => {
        return e?.textContent;
      }, inner);
      expect(content).toBe('A');
    });

    it('should return null for non-existing element', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><div class="second"><div class="inner">B</div></div></body></html>'
      );
      using html = (await page.$('html'))!;
      using second = await html.$('.third');
      expect(second).toBe(null);
    });
  });
  describe('ElementHandle.$eval', function () {
    it('should work', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><div class="tweet"><div class="like">100</div><div class="retweets">10</div></div></body></html>'
      );
      using tweet = (await page.$('.tweet'))!;
      const content = await tweet.$eval('.like', node => {
        return (node as HTMLElement).innerText;
      });
      expect(content).toBe('100');
    });

    it('should retrieve content from subtree', async () => {
      const {page} = await getTestState();

      const htmlContent =
        '<div class="a">not-a-child-div</div><div id="myId"><div class="a">a-child-div</div></div>';
      await page.setContent(htmlContent);
      using elementHandle = (await page.$('#myId'))!;
      const content = await elementHandle.$eval('.a', node => {
        return (node as HTMLElement).innerText;
      });
      expect(content).toBe('a-child-div');
    });

    it('should throw in case of missing selector', async () => {
      const {page} = await getTestState();

      const htmlContent =
        '<div class="a">not-a-child-div</div><div id="myId"></div>';
      await page.setContent(htmlContent);
      using elementHandle = (await page.$('#myId'))!;
      const errorMessage = await elementHandle
        .$eval('.a', node => {
          return (node as HTMLElement).innerText;
        })
        .catch(error => {
          return error.message;
        });
      expect(errorMessage).toBe(
        `Error: failed to find element matching selector ".a"`
      );
    });
  });
  describe('ElementHandle.$$eval', function () {
    it('should work', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><div class="tweet"><div class="like">100</div><div class="like">10</div></div></body></html>'
      );
      using tweet = (await page.$('.tweet'))!;
      const content = await tweet.$$eval('.like', nodes => {
        return (nodes as HTMLElement[]).map(n => {
          return n.innerText;
        });
      });
      expect(content).toEqual(['100', '10']);
    });

    it('should retrieve content from subtree', async () => {
      const {page} = await getTestState();

      const htmlContent =
        '<div class="a">not-a-child-div</div><div id="myId"><div class="a">a1-child-div</div><div class="a">a2-child-div</div></div>';
      await page.setContent(htmlContent);
      using elementHandle = (await page.$('#myId'))!;
      const content = await elementHandle.$$eval('.a', nodes => {
        return (nodes as HTMLElement[]).map(n => {
          return n.innerText;
        });
      });
      expect(content).toEqual(['a1-child-div', 'a2-child-div']);
    });

    it('should not throw in case of missing selector', async () => {
      const {page} = await getTestState();

      const htmlContent =
        '<div class="a">not-a-child-div</div><div id="myId"></div>';
      await page.setContent(htmlContent);
      using elementHandle = (await page.$('#myId'))!;
      const nodesLength = await elementHandle.$$eval('.a', nodes => {
        return nodes.length;
      });
      expect(nodesLength).toBe(0);
    });
  });

  describe('ElementHandle.$$', function () {
    it('should query existing elements', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><div>A</div><br/><div>B</div></body></html>'
      );
      using html = (await page.$('html'))!;
      const elements = await html.$$('div');
      expect(elements).toHaveLength(2);
      const promises = elements.map(element => {
        return page.evaluate((e: HTMLElement) => {
          return e.textContent;
        }, element);
      });
      expect(await Promise.all(promises)).toEqual(['A', 'B']);
    });

    it('should return empty array for non-existing elements', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><span>A</span><br/><span>B</span></body></html>'
      );
      using html = (await page.$('html'))!;
      const elements = await html.$$('div');
      expect(elements).toHaveLength(0);
    });
  });

  describe('ElementHandle.$x', function () {
    it('should query existing element', async () => {
      const {page, server} = await getTestState();

      await page.goto(server.PREFIX + '/playground.html');
      await page.setContent(
        '<html><body><div class="second"><div class="inner">A</div></div></body></html>'
      );
      using html = (await page.$('html'))!;
      const second = await html.$x(`./body/div[contains(@class, 'second')]`);
      const inner = await second[0]!.$x(`./div[contains(@class, 'inner')]`);
      const content = await page.evaluate(e => {
        return e.textContent;
      }, inner[0]!);
      expect(content).toBe('A');
    });

    it('should return null for non-existing element', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><div class="second"><div class="inner">B</div></div></body></html>'
      );
      using html = (await page.$('html'))!;
      const second = await html.$x(`/div[contains(@class, 'third')]`);
      expect(second).toEqual([]);
    });
  });

  // This is the same tests for `$$eval` and `$$` as above, but with a queryAll
  // handler that returns an array instead of a list of nodes.
  describe('QueryAll', function () {
    const handler: CustomQueryHandler = {
      queryAll: (element, selector) => {
        return [...(element as Element).querySelectorAll(selector)];
      },
    };
    before(() => {
      Puppeteer.registerCustomQueryHandler('allArray', handler);
    });

    it('should have registered handler', async () => {
      expect(
        Puppeteer.customQueryHandlerNames().includes('allArray')
      ).toBeTruthy();
    });
    it('$$ should query existing elements', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><div>A</div><br/><div>B</div></body></html>'
      );
      using html = (await page.$('html'))!;
      const elements = await html.$$('allArray/div');
      expect(elements).toHaveLength(2);
      const promises = elements.map(element => {
        return page.evaluate(e => {
          return e.textContent;
        }, element);
      });
      expect(await Promise.all(promises)).toEqual(['A', 'B']);
    });

    it('$$ should return empty array for non-existing elements', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<html><body><span>A</span><br/><span>B</span></body></html>'
      );
      using html = (await page.$('html'))!;
      const elements = await html.$$('allArray/div');
      expect(elements).toHaveLength(0);
    });
    it('$$eval should work', async () => {
      const {page} = await getTestState();

      await page.setContent(
        '<div>hello</div><div>beautiful</div><div>world!</div>'
      );
      const divsCount = await page.$$eval('allArray/div', divs => {
        return divs.length;
      });
      expect(divsCount).toBe(3);
    });
    it('$$eval should accept extra arguments', async () => {
      const {page} = await getTestState();
      await page.setContent(
        '<div>hello</div><div>beautiful</div><div>world!</div>'
      );
      const divsCountPlus5 = await page.$$eval(
        'allArray/div',
        (divs, two, three) => {
          return divs.length + (two as number) + (three as number);
        },
        2,
        3
      );
      expect(divsCountPlus5).toBe(8);
    });
    it('$$eval should accept ElementHandles as arguments', async () => {
      const {page} = await getTestState();
      await page.setContent(
        '<section>2</section><section>2</section><section>1</section><div>3</div>'
      );
      using divHandle = (await page.$('div'))!;
      const sum = await page.$$eval(
        'allArray/section',
        (sections, div) => {
          return (
            sections.reduce((acc, section) => {
              return acc + Number(section.textContent);
            }, 0) + Number((div as HTMLElement).textContent)
          );
        },
        divHandle
      );
      expect(sum).toBe(8);
    });
    it('$$eval should handle many elements', async function () {
      this.timeout(25_000);

      const {page} = await getTestState();
      await page.evaluate(
        `
        for (var i = 0; i <= 1000; i++) {
            const section = document.createElement('section');
            section.textContent = i;
            document.body.appendChild(section);
        }
        `
      );
      const sum = await page.$$eval('allArray/section', sections => {
        return sections.reduce((acc, section) => {
          return acc + Number(section.textContent);
        }, 0);
      });
      expect(sum).toBe(500500);
    });
  });
});