pdfme/packages/pdf-lib/__tests__/utils/strings.spec.ts

import fontkit from '@pdf-lib/fontkit';
import { FontNames } from '@pdf-lib/standard-fonts';
import fs from 'fs';

import { CustomFontEmbedder, StandardFontEmbedder } from '../../src/core';
import { breakTextIntoLines } from '../../src/utils';

const font = StandardFontEmbedder.for(FontNames.Helvetica);

const textSize = 24;

const computeTextWidth = (text: string) =>
  font.widthOfTextAtSize(text, textSize);

describe(`breakTextIntoLines`, () => {
  it(`handles empty wordBreaks arrays`, () => {
    const input = 'foobar-quxbaz';
    const expected = ['foobar-quxbaz'];
    const actual = breakTextIntoLines(input, [], 21, computeTextWidth);
    expect(actual).toEqual(expected);
  });

  it(`handles trailing newlines`, () => {
    const input = 'foo\n';
    const expected = ['foo'];
    const actual = breakTextIntoLines(input, [], 21, computeTextWidth);
    expect(actual).toEqual(expected);
  });

  it(`handles trailing carriage returns`, () => {
    const input = 'foo\r';
    const expected = ['foo'];
    const actual = breakTextIntoLines(input, [], 21, computeTextWidth);
    expect(actual).toEqual(expected);
  });

  it(`always breaks lines when EOLs are encountered`, () => {
    const input = 'foo\nbar-qux\rbaz\n';
    const expected = ['foo', 'bar-qux', 'baz'];
    const actual = breakTextIntoLines(input, [], 90000, computeTextWidth);
    expect(actual).toEqual(expected);
  });

  it(`breaks at the last possible 'wordBreak' before exceeding 'maxWidth' (1)`, () => {
    const input =
      'Lorem Test ipsum dolor sit amet, consectetur adipiscing\nelit';
    const expected = [
      'Lorem T',
      'est ipsu',
      'm dolor s',
      'it amet, c',
      'onsectet',
      'ur adipis',
      'cing',
      'elit',
    ];
    const actual = breakTextIntoLines(
      input,
      ['', 'Test'],
      100,
      computeTextWidth,
    );
    expect(actual).toEqual(expected);
  });

  it(`breaks at the last possible 'wordBreak' before exceeding 'maxWidth' (2)`, () => {
    const input = 'Foo%bar%baz';
    const expected = ['Foo%', 'bar%baz'];
    const actual = breakTextIntoLines(input, ['%'], 100, computeTextWidth);
    expect(actual).toEqual(expected);
  });

  it(`handles non-ascii code points and empty breaks`, async () => {
    const sourceHansBytes = fs.readFileSync(
      'assets/fonts/source_hans_jp/SourceHanSerifJP-Regular.otf',
    );
    const sourceHansFont = await CustomFontEmbedder.for(
      fontkit,
      sourceHansBytes,
    );

    const input =
      '遅未亮惑職界転藤柔索名午納，問通桑転加料演載満経信回込町者訟窃。';
    const expected = [
      '遅未亮惑職',
      '界転藤柔索',
      '名午納，問',
      '通桑転加料',
      '演載満経信',
      '回込町者訟',
      '窃。',
    ];
    const actual = breakTextIntoLines(input, [''], 125, (text: string) =>
      sourceHansFont.widthOfTextAtSize(text, 24),
    );
    expect(actual).toEqual(expected);
  });
});