def test_text_underline_thickness(assert_pixels):
    assert_pixels('''
        _____________
        _zzzzzzzzzzz_
        _zRRRRRRRRRz_
        _zRRRRRRRRRz_
        _zzzzzzzzzzz_
        _zzzzzzzzzzz_
        _zBBBBBBBBBz_
        _zBBBBBBBBBz_
        _zzzzzzzzzzz_
    ''', '''
      <style>
        @page {
          size: 13px 9px;
          margin: 2px;
        }
        body {
          color: red;
          font-family: weasyprint;
          font-size: 3px;
          text-decoration: underline blue 3px;
          text-underline-offset: 2px;
        }
      </style>
      <div>abc</div>''')
,
tests/draw/test_text.py