add xls converter with tests

src/markitdown/_markitdown.py

@@ -723,7 +723,30 @@ def convert(self, local_path, **kwargs) -> Union[None, DocumentConverterResult]:
         if extension.lower() != ".xlsx":
             return None
 
-        sheets = pd.read_excel(local_path, sheet_name=None)
+        sheets = pd.read_excel(local_path, sheet_name=None, engine="openpyxl")
+        md_content = ""
+        for s in sheets:
+            md_content += f"## {s}\n"
+            html_content = sheets[s].to_html(index=False)
+            md_content += self._convert(html_content).text_content.strip() + "\n\n"
+
+        return DocumentConverterResult(
+            title=None,
+            text_content=md_content.strip(),
+        )
+
+class XlsConverter(HtmlConverter):
+    """
+    Converts XLS files to Markdown, with each sheet presented as a separate Markdown table.
+    """
+
+    def convert(self, local_path, **kwargs) -> Union[None, DocumentConverterResult]:
+        # Bail if not a XLS
+        extension = kwargs.get("file_extension", "")
+        if extension.lower() != ".xls":
+            return None
+
+        sheets = pd.read_excel(local_path, sheet_name=None, engine="xlrd")
         md_content = ""
         for s in sheets:
             md_content += f"## {s}\n"
@@ -1277,6 +1300,7 @@ def __init__(
         self.register_page_converter(BingSerpConverter())
         self.register_page_converter(DocxConverter())
         self.register_page_converter(XlsxConverter())
+        self.register_page_converter(XlsConverter())
         self.register_page_converter(PptxConverter())
         self.register_page_converter(WavConverter())
         self.register_page_converter(Mp3Converter())

tests/test_markitdown.py

@@ -54,6 +54,12 @@
     "affc7dad-52dc-4b98-9b5d-51e65d8a8ad0",
 ]
 
+XLS_TEST_STRINGS = [
+    "## 09060124-b5e7-4717-9d07-3c046eb",
+    "6ff4173b-42a5-4784-9b19-f49caff4d93d",
+    "affc7dad-52dc-4b98-9b5d-51e65d8a8ad0",
+]
+
 DOCX_TEST_STRINGS = [
     "314b0a30-5b04-470b-b9f7-eed2c2bec74a",
     "49e168b7-d2ae-407f-a055-2167576f39a1",
@@ -167,6 +173,12 @@ def test_markitdown_local() -> None:
         text_content = result.text_content.replace("\\", "")
         assert test_string in text_content
 
+    # Test XLS processing
+    result = markitdown.convert(os.path.join(TEST_FILES_DIR, "test.xls"))
+    for test_string in XLS_TEST_STRINGS:
+        text_content = result.text_content.replace("\\", "")
+        assert test_string in text_content
+
     # Test DOCX processing
     result = markitdown.convert(os.path.join(TEST_FILES_DIR, "test.docx"))
     for test_string in DOCX_TEST_STRINGS: