test(table): improve HTML validation for table extraction

- Add lxml dependency for HTML parsing
- Update test case to use XPath and HTML parser for structure and content validation
- Check for presence of essential HTML elements like <table>, <thead>, <tbody>, <tr>, and <td>
- Validate column headers and specific row contents

tests/test_table/test_tablemaster.py

 import unittest
 from PIL import Image
+from lxml import etree
+
 from magic_pdf.model.ppTableModel import ppTableModel
 
 class TestppTableModel(unittest.TestCase):
@@ -10,8 +12,44 @@ class TestppTableModel(unittest.TestCase):
                   "model_dir": "D:/models/PDF-Extract-Kit/models/TabRec/TableMaster"}
         table_model = ppTableModel(config)
         res = table_model.img2html(img)
-        true_value = """<td><table  border="1"><thead><tr><td><b>Methods</b></td><td><b>R</b></td><td><b>P</b></td><td><b>F</b></td><td><b>FPS</b></td></tr></thead><tbody><tr><td>SegLink [26]</td><td>70.0</td><td>86.0</td><td>77.0</td><td>8.9</td></tr><tr><td>PixelLink [4]</td><td>73.2</td><td>83.0</td><td>77.8</td><td>-</td></tr><tr><td>TextSnake [18]</td><td>73.9</td><td>83.2</td><td>78.3</td><td>1.1</td></tr><tr><td>TextField [37]</td><td>75.9</td><td>87.4</td><td>81.3</td><td>5.2 </td></tr><tr><td>MSR[38]</td><td>76.7</td><td>87.4</td><td>81.7</td><td>-</td></tr><tr><td>FTSN[3]</td><td>77.1</td><td>87.6</td><td>82.0</td><td>-</td></tr><tr><td>LSE[30]</td><td>81.7</td><td>84.2</td><td>82.9</td><td>-</td></tr><tr><td>CRAFT [2]</td><td>78.2</td><td>88.2</td><td>82.9</td><td>8.6</td></tr><tr><td>MCN [16]</td><td>79</td><td>88.</td><td>83</td><td>-</td></tr><tr><td>ATRR[35]</td><td>82.1</td><td>85.2</td><td>83.6</td><td>-</td></tr><tr><td>PAN [34]</td><td>83.8</td><td>84.4</td><td>84.1</td><td>30.2</td></tr><tr><td>DB[12]</td><td>79.2</td><td>91.5</td><td>84.9</td><td>32.0</td></tr><tr><td>DRRG [41]</td><td>82.30</td><td>88.05</td><td>85.08</td><td>-</td></tr><tr><td>Ours (SynText)</td><td>80.68</td><td>85.40</td><td>82.97</td><td>12.68</td></tr><tr><td>Ours (MLT-17)</td><td>84.54</td><td>86.62</td><td>85.57</td><td>12.31</td></tr></tbody></table></td>\n"""
-        self.assertEqual(true_value, res)
+        # 验证生成的 HTML 是否符合预期
+        parser = etree.HTMLParser()
+        tree = etree.fromstring(res, parser)
+
+        # 检查 HTML 结构
+        assert tree.find('.//table') is not None, "HTML should contain a <table> element"
+        assert tree.find('.//thead') is not None, "HTML should contain a <thead> element"
+        assert tree.find('.//tbody') is not None, "HTML should contain a <tbody> element"
+        assert tree.find('.//tr') is not None, "HTML should contain a <tr> element"
+        assert tree.find('.//td') is not None, "HTML should contain a <td> element"
+
+        # 检查具体的表格内容
+        headers = tree.xpath('//thead/tr/td/b')
+        print(headers)  # Print headers for debugging
+        assert len(headers) == 5, "Thead should have 5 columns"
+        assert headers[0].text and headers[0].text.strip() == "Methods", "First header should be 'Methods'"
+        assert headers[1].text and headers[1].text.strip() == "R", "Second header should be 'R'"
+        assert headers[2].text and headers[2].text.strip() == "P", "Third header should be 'P'"
+        assert headers[3].text and headers[3].text.strip() == "F", "Fourth header should be 'F'"
+        assert headers[4].text and headers[4].text.strip() == "FPS", "Fifth header should be 'FPS'"
+
+        # 检查第一行数据
+        first_row = tree.xpath('//tbody/tr[1]/td')
+        assert len(first_row) == 5, "First row should have 5 cells"
+        assert first_row[0].text and first_row[0].text.strip() == "SegLink[26]", "First cell should be 'SegLink[26]'"
+        assert first_row[1].text and first_row[1].text.strip() == "70.0", "Second cell should be '70.0'"
+        assert first_row[2].text and first_row[2].text.strip() == "86.0", "Third cell should be '86.0'"
+        assert first_row[3].text and first_row[3].text.strip() == "77.0", "Fourth cell should be '77.0'"
+        assert first_row[4].text and first_row[4].text.strip() == "8.9", "Fifth cell should be '8.9'"
+
+        # 检查倒数第二行数据
+        second_last_row = tree.xpath('//tbody/tr[position()=last()-1]/td')
+        assert len(second_last_row) == 5, "second_last_row should have 5 cells"
+        assert second_last_row[0].text and second_last_row[0].text.strip() == "Ours (SynText)", "First cell should be 'Ours (SynText)'"
+        assert second_last_row[1].text and second_last_row[1].text.strip() == "80.68", "Second cell should be '80.68'"
+        assert second_last_row[2].text and second_last_row[2].text.strip() == "85.40", "Third cell should be '85.40'"
+        assert second_last_row[3].text and second_last_row[3].text.strip() == "82.97", "Fourth cell should be '82.97'"
+        assert second_last_row[3].text and second_last_row[4].text.strip() == "12.68", "Fifth cell should be '12.68'"
 
 
 if __name__ == "__main__":