signal-desktop/test/modules/link_previews_test.js

const { assert } = require('chai');

const {
  findLinks,
  isLinkSafeToPreview,
  isLinkSneaky,
} = require('../../js/modules/link_previews');

describe('Link previews', () => {
  describe('#isLinkSafeToPreview', () => {
    it('returns false for invalid URLs', () => {
      assert.isFalse(isLinkSafeToPreview(''));
      assert.isFalse(isLinkSafeToPreview('https'));
      assert.isFalse(isLinkSafeToPreview('https://'));
      assert.isFalse(isLinkSafeToPreview('https://bad url'));
      assert.isFalse(isLinkSafeToPreview('example.com'));
    });

    it('returns false for non-HTTPS URLs', () => {
      assert.isFalse(isLinkSafeToPreview('http://example.com'));
      assert.isFalse(isLinkSafeToPreview('ftp://example.com'));
      assert.isFalse(isLinkSafeToPreview('file://example'));
    });

    it('returns false if the link is "sneaky"', () => {
      // See `isLinkSneaky` tests below for more thorough checking.
      assert.isFalse(isLinkSafeToPreview('https://user:pass@example.com'));
      assert.isFalse(isLinkSafeToPreview('https://aquí.example'));
      assert.isFalse(isLinkSafeToPreview('https://aqu%C3%AD.example'));
    });

    it('returns true for "safe" urls', () => {
      assert.isTrue(isLinkSafeToPreview('https://example.com'));
      assert.isTrue(
        isLinkSafeToPreview('https://example.com/foo/bar?query=string#hash')
      );
    });
  });

  describe('#findLinks', () => {
    it('returns all links if no caretLocation is provided', () => {
      const text =
        'Check out this link: https://github.com/signalapp/Signal-Desktop\nAnd this one too: https://github.com/signalapp/Signal-Android';

      const expected = [
        'https://github.com/signalapp/Signal-Desktop',
        'https://github.com/signalapp/Signal-Android',
      ];

      const actual = findLinks(text);
      assert.deepEqual(expected, actual);
    });

    it('includes all links if cursor is not in a link', () => {
      const text =
        'Check out this link: https://github.com/signalapp/Signal-Desktop\nAnd this one too: https://github.com/signalapp/Signal-Android';
      const caretLocation = 10;

      const expected = [
        'https://github.com/signalapp/Signal-Desktop',
        'https://github.com/signalapp/Signal-Android',
      ];

      const actual = findLinks(text, caretLocation);
      assert.deepEqual(expected, actual);
    });

    it('excludes a link not at the end if the caret is inside of it', () => {
      const text =
        'Check out this link: https://github.com/signalapp/Signal-Desktop\nAnd this one too: https://github.com/signalapp/Signal-Android';
      const caretLocation = 30;

      const expected = ['https://github.com/signalapp/Signal-Android'];

      const actual = findLinks(text, caretLocation);
      assert.deepEqual(expected, actual);
    });

    it('excludes a link not at the end if the caret is at its end', () => {
      const text =
        'Check out this link: https://github.com/signalapp/Signal-Desktop\nAnd this one too: https://github.com/signalapp/Signal-Android';
      const caretLocation = 64;

      const expected = ['https://github.com/signalapp/Signal-Android'];

      const actual = findLinks(text, caretLocation);
      assert.deepEqual(expected, actual);
    });

    it('excludes a link at the end of the caret is inside of it', () => {
      const text =
        'Check out this link: https://github.com/signalapp/Signal-Desktop\nAnd this one too: https://github.com/signalapp/Signal-Android';
      const caretLocation = 100;

      const expected = ['https://github.com/signalapp/Signal-Desktop'];

      const actual = findLinks(text, caretLocation);
      assert.deepEqual(expected, actual);
    });

    it('includes link at the end if cursor is at its end', () => {
      const text =
        'Check out this link: https://github.com/signalapp/Signal-Desktop\nAnd this one too: https://github.com/signalapp/Signal-Android';
      const caretLocation = text.length;

      const expected = [
        'https://github.com/signalapp/Signal-Desktop',
        'https://github.com/signalapp/Signal-Android',
      ];

      const actual = findLinks(text, caretLocation);
      assert.deepEqual(expected, actual);
    });
  });

  describe('#isLinkSneaky', () => {
    it('returns false for all-latin domain', () => {
      const link = 'https://www.amazon.com';
      const actual = isLinkSneaky(link);
      assert.strictEqual(actual, false);
    });

    it('returns false for IPv4 addresses', () => {
      assert.isFalse(isLinkSneaky('https://127.0.0.1/path'));
    });

    // It's possible that this should return `false` but we'd need to add special logic
    //   for it.
    it('returns true for IPv6 addresses', () => {
      assert.isTrue(
        isLinkSneaky('https://[2001:0db8:85a3:0000:0000:8a2e:0370:7334]/path')
      );
      assert.isTrue(isLinkSneaky('https://[::]/path'));
    });

    it('returns true for Latin + Cyrillic domain', () => {
      const link = 'https://www.aмazon.com';
      const actual = isLinkSneaky(link);
      assert.strictEqual(actual, true);
    });

    it('returns true for Latin + Greek domain', () => {
      const link = 'https://www.αpple.com';
      const actual = isLinkSneaky(link);
      assert.strictEqual(actual, true);
    });

    it('returns true for ASCII and non-ASCII mix', () => {
      const link = 'https://www.аррӏе.com';
      const actual = isLinkSneaky(link);
      assert.strictEqual(actual, true);
    });

    it('returns true for Latin + High Greek domain', () => {
      const link = `https://www.apple${String.fromCodePoint(0x101a0)}.com`;
      const actual = isLinkSneaky(link);
      assert.strictEqual(actual, true);
    });

    it('returns true for =', () => {
      const link = 'r.id=s.id';
      assert.strictEqual(isLinkSneaky(link), true);
    });

    it('returns true for $', () => {
      const link = 'r.id$s.id';
      assert.strictEqual(isLinkSneaky(link), true);
    });

    it('returns true for +', () => {
      const link = 'r.id+s.id';
      assert.strictEqual(isLinkSneaky(link), true);
    });

    it('returns true for ^', () => {
      const link = 'r.id^s.id';
      assert.strictEqual(isLinkSneaky(link), true);
    });

    it('returns true for auth (or pretend auth)', () => {
      const link = 'http://whatever.com&login=someuser@77777777';
      assert.strictEqual(isLinkSneaky(link), true);
    });

    it("returns true if the domain doesn't contain a .", () => {
      assert.isTrue(isLinkSneaky('https://example'));
      assert.isTrue(isLinkSneaky('https://localhost'));
      assert.isTrue(isLinkSneaky('https://localhost:3000'));
    });

    it('returns true if the domain has any empty labels', () => {
      assert.isTrue(isLinkSneaky('https://example.'));
      assert.isTrue(isLinkSneaky('https://example.com.'));
      assert.isTrue(isLinkSneaky('https://.example.com'));
      assert.isTrue(isLinkSneaky('https://..example.com'));
    });

    it('returns true if the domain is longer than 2048 UTF-16 code points', () => {
      const domain = `${'a'.repeat(2041)}.example`;
      assert.lengthOf(domain, 2049, 'Test domain is the incorrect length');
      const link = `https://${domain}/foo/bar`;
      assert.isTrue(isLinkSneaky(link));
    });

    it('returns false for regular @ in url', () => {
      const link =
        'https://lbry.tv/@ScammerRevolts:b0/DELETING-EVERY-FILE-OFF-A-SCAMMERS-LAPTOP-Destroyed:1';
      assert.strictEqual(isLinkSneaky(link), false);
    });
  });
});