diff --git a/.github/workflows/pylint.yml b/.github/workflows/pylint.yml
index bffc0b4..6399503 100644
--- a/.github/workflows/pylint.yml
+++ b/.github/workflows/pylint.yml
@@ -18,6 +18,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install pylint
+        pip install pytest
     - name: Analysing the code with pylint
       run: |
         pylint $(git ls-files '*.py')
diff --git a/src/markdown_helper/__init__.py b/src/markdown_helper/__init__.py
index b60ff6b..35ba930 100644
--- a/src/markdown_helper/__init__.py
+++ b/src/markdown_helper/__init__.py
@@ -109,6 +109,8 @@ def sort_table(self, disable_convert: bool = False):
             # If multiple sort keys are provided, prioritize the first one, then the second, etc.
             sort_keys = self.sort_key.split(",")
             for sort_key in sort_keys:
+                if sort_key not in self.headers:
+                    raise ValueError(f"sort_key {sort_key} not in headers")
                 if disable_convert:
                     self.rows = sorted(
                         self.rows,
@@ -243,8 +245,10 @@ def __str__(self):
             return self.html()
         return self.markdown()
     def __repr__(self):
-        return f"""Image(url={self.url}, title={self.title}, alt={self.alt},
-          width={self.width}, height={self.height}, align={self.align}, caption={self.caption})"""
+        return_string = f"Image(url={self.url}, title={self.title}, alt={self.alt}"
+        return_string += f", width={self.width}, height={self.height}, align={self.align},"
+        return_string +=f"caption={self.caption})"
+        return return_string
 
 
 class Link:
diff --git a/tests/test_markdown.py b/tests/test_markdown.py
index 298f826..e2afb3a 100644
--- a/tests/test_markdown.py
+++ b/tests/test_markdown.py
@@ -1,13 +1,18 @@
 """
 This file contains the pytest tests for the markdown_helper.py file.
 """
+import pytest
 try:
     from src import markdown_helper as markdown
 except ModuleNotFoundError:
     try:
         import markdown_helper as markdown
     except ModuleNotFoundError:
-        from ..src import markdown_helper as markdown # pylint: disable=import-error, relative-beyond-top-level
+        from ..src import (  # pylint: disable=relative-beyond-top-level
+            markdown_helper as markdown,  # pylint: disable=import-error
+        )  # pylint: disable=relative-beyond-top-level
+
+
 def test_ordered_list():
     """
     This function tests the markdown.List class.
@@ -18,6 +23,16 @@ def test_ordered_list():
     ), "String representation of ordered list is incorrect."
     assert list_1.items == ["item 1", "item 2", "item 3"], "List items are incorrect."
 
+def test_empty_list():
+    """
+    This function tests the markdown.List class.
+    """
+    list_1: markdown.List = markdown.List([], ordered=True)
+    assert (
+        str(list_1) == ""
+    ), "String representation of ordered list is incorrect."
+    assert list_1.items == [], "List items are incorrect."
+    assert repr(list_1) == "List(title=False, items=[], ordered=True)", "List items are incorrect."
 
 def test_modify_list():
     """
@@ -69,6 +84,9 @@ def test_link():
     ), "String representation of link is incorrect."
     assert link_1.url == "http://www.google.com", "Link URL is incorrect."
     assert link_1.text == "Google", "Link text is incorrect."
+    assert (
+        repr(link_1) == "Link(url=http://www.google.com, text=Google, title=False, new_tab=False)"
+    )
 
 
 def test_link_no_trailing():
@@ -119,6 +137,22 @@ def test_image():
     assert image_1.alt == "Google", "Image text is incorrect."
 
 
+def test_image_texts():
+    """
+    This function tests the markdown.Image class.
+    """
+    image_1 = markdown.Image(
+        "http://www.google.com", alt="Google", title="Title", caption="Caption"
+    )
+    assert (
+        image_1.markdown() == "### Title\n![Google](http://www.google.com)\n_Caption_\n"
+    ), "Markdown string representation of image is incorrect."
+    assert (
+        repr(image_1)
+        == "Image(url=http://www.google.com, title=Title, alt=Google, width=False, height=False, align=False,caption=Caption)"  # pylint: disable=line-too-long
+    ), "String representation of image is incorrect."
+
+
 def test_image_size():
     """
     This function tests the markdown.Image class.
@@ -182,6 +216,7 @@ def test_table_add_row():
         {"col 1": "item 1", "col 2": "item 2", "col 3": "item 3"}
     ], "Table rows are incorrect."
 
+
 def test_table_add_row_no_headers():
     """
     This function tests the table.add_row function with a list input.
@@ -202,6 +237,23 @@ def test_table_add_row_no_headers():
     ], "Table rows are incorrect."
 
 
+def test_table_title():
+    """
+    This function tests the markdown.Table class.
+    """
+    table_1 = markdown.Table(["col 1", "col 2", "col 3"], title="My Table")
+    table_1.add_row({"col 1": "value 1", "col 2": "value 2", "col 3": "value 3"})
+    assert (
+        str(table_1)
+        == "### My Table\n| col 1 | col 2 | col 3 |\n| --- | --- | --- |\n| value 1 | value 2 | value 3 |\n" # pylint: disable=line-too-long
+    ), "String representation of table is incorrect."
+    assert table_1.headers == [
+        "col 1",
+        "col 2",
+        "col 3",
+    ], "Table columns are incorrect."
+    assert table_1.title == "My Table", "Table title is incorrect."
+
 
 def test_table_sort():
     """
@@ -214,21 +266,63 @@ def test_table_sort():
     table_1.add_row({"Name": "Third", "Value": 3})
     assert (
         str(table_1)
-        == "| Name | Value |\n| --- | --- |\n| First | 1 |\n| Second | 2 |\n| Third | 3 |\n| Fourth | 4 |\n" # pylint: disable=line-too-long
+        == "| Name | Value |\n| --- | --- |\n| First | 1 |\n| Second | 2 |\n| Third | 3 |\n| Fourth | 4 |\n"  # pylint: disable=line-too-long
     ), "Sorted Table is incorrect."
     assert table_1.headers == ["Name", "Value"], "Table columns are incorrect."
     table_1.sort_reverse = True
     assert (
         str(table_1)
-        == "| Name | Value |\n| --- | --- |\n| Fourth | 4 |\n| Third | 3 |\n| Second | 2 |\n| First | 1 |\n" # pylint: disable=line-too-long
+        == "| Name | Value |\n| --- | --- |\n| Fourth | 4 |\n| Third | 3 |\n| Second | 2 |\n| First | 1 |\n"  # pylint: disable=line-too-long
     ), "Reverse sorted Table is incorrect."
     table_1.sort_reverse = False
     table_1.sort_key = "Name"
     assert (
         str(table_1)
-        == "| Name | Value |\n| --- | --- |\n| First | 1 |\n| Fourth | 4 |\n| Second | 2 |\n| Third | 3 |\n" # pylint: disable=line-too-long
+        == "| Name | Value |\n| --- | --- |\n| First | 1 |\n| Fourth | 4 |\n| Second | 2 |\n| Third | 3 |\n"  # pylint: disable=line-too-long
     ), "Second sorted Table is incorrect."
 
+def test_table_sort_error():
+    """
+    This function tests the markdown.Table class.
+    """
+    table_1 = markdown.Table(["Name", "Value"], sort_key="Value")
+    table_1.add_row({"Name": "First", "Value": 1})
+    table_1.add_row({"Name": "Second", "Value": False})
+    table_1.add_row({"Name": "Fourth", "Value": 4})
+    table_1.add_row({"Name": "Third", "Value": "String"})
+    with pytest.raises(ValueError):
+        table_1.sort_key = "invalid"
+        table_1.sort_table()
+
+def test_table_disable_convert():
+    """
+    This function tests the markdown.Table class.
+    """
+    table_1 = markdown.Table(["Name", "Value"], sort_key="Value")
+    table_1.add_row({"Name": "First", "Value": 1})
+    table_1.add_row({"Name": "Second", "Value": 0})
+    table_1.add_row({"Name": "Fourth", "Value": 1})
+    table_1.add_row({"Name": "Third", "Value": 0})
+    table_1.sort_table(True)
+    assert (
+        table_1.rows == [{'Name': 'Second', 'Value': 0}, {'Name': 'Third', 'Value': 0},
+                        {'Name': 'First', 'Value': 1}, {'Name': 'Fourth', 'Value': 1}]
+    ), "Sorted Table is incorrect."
+
+def test_table_sort_convert():
+    """
+    This function tests the markdown.Table class.
+    """
+    table_1 = markdown.Table(["Name", "Value"], sort_key="Value")
+    table_1.add_row({"Name": "First", "Value": 1})
+    table_1.add_row({"Name": "Second", "Value": 0})
+    table_1.add_row({"Name": "Fourth", "Value": 1})
+    table_1.add_row({"Name": "Third", "Value": 0})
+    table_1.sort_table()
+    assert (
+        table_1.rows == [{'Name': 'Second', 'Value': False}, {'Name': 'Third', 'Value': False},
+                        {'Name': 'First', 'Value': True}, {'Name': 'Fourth', 'Value': True}]
+    ), "Sorted Table is incorrect."
 
 def test_table_flexible():
     """
@@ -241,11 +335,55 @@ def test_table_flexible():
     table_1.add_row({"Name": "Fourth", "Value": 4})
     assert (
         str(table_1)
-        == "| Name | Value | Extra |\n| --- | --- | --- |\n| First | 1 |  |\n| Second | 2 |  |\n| Third | 3 | Extra Value |\n| Fourth | 4 |  |\n" # pylint: disable=line-too-long
+        == "| Name | Value | Extra |\n| --- | --- | --- |\n| First | 1 |  |\n| Second | 2 |  |\n| Third | 3 | Extra Value |\n| Fourth | 4 |  |\n"  # pylint: disable=line-too-long
     ), "Flexible Table is incorrect."
     assert table_1.headers == ["Name", "Value", "Extra"], "Table columns are incorrect."
 
+def test_table_add_rows():
+    """
+    This function tests the markdown.Table class.
+    """
+    table_1 = markdown.Table(["Name", "Value"])
+    table_1.add_rows([{"Name": "First", "Value": 1}, {"Name": "Second", "Value": 2}])
+    assert (
+        str(table_1)
+        == "| Name | Value |\n| --- | --- |\n| First | 1 |\n| Second | 2 |\n"
+    ), "Table is incorrect."
+    assert table_1.headers == ["Name", "Value"], "Table columns are incorrect."
 
+def test_table_remap():
+    """
+    This function tests the markdown.Table class.
+    """
+    table_1 = markdown.Table(["Name", "Value"], custom_map={"Name":{"First":"1st","Second":"2nd"}})
+    table_1.add_row({"Name": "First", "Value": 1})
+    table_1.add_row({"Name": "Second", "Value": 2})
+    assert (
+        str(table_1.get_table())
+        == "| Name | Value |\n| --- | --- |\n| 1st | 1 |\n| 2nd | 2 |\n"  # pylint: disable=line-too-long
+    ), "Remapped Table is incorrect."
+    assert table_1.headers == ["Name", "Value"], "Table columns are incorrect."
+    table_2 = markdown.Table(["Name", "Value"], custom_map={"Name":{"First":"1st","Second":"2nd"}})
+    table_2.add_row({"Name": "First", "Value": 1})
+    table_2.remap()
+    assert (
+        str(table_2)
+        == "| Name | Value |\n| --- | --- |\n| 1st | 1 |\n"  # pylint: disable=line-too-long
+    ), "Remapped Table is incorrect."
+
+
+def test_header():
+    """
+    This function tests the markdown.Header class.
+    """
+    header_1 = markdown.Header("Header 1", 2)
+    assert (
+        str(header_1) == "## Header 1"
+    ), "String representation of header is incorrect."
+    assert header_1.text == "Header 1", "Header text is incorrect."
+    assert (
+        repr(header_1) == "## Header 1"
+    )
 def test_section():
     """
     This function tests the markdown.Section class.
@@ -266,6 +404,23 @@ def test_section_add():
     assert (
         str(section_1) == "# Section 1\nThis is a paragraph.  \n"
     ), "String representation of section is incorrect."
+    assert section_1.title.text == "Section 1", "Section title is incorrect."
+    assert (
+        repr(section_1) == "Section(title=# Section 1, content=This is a paragraph.  )"
+    ), "Section representation is incorrect."
+
+
+def test_section_add_nonempty():
+    """
+    This function tests the markdown.Section class.
+    """
+    section_1 = markdown.Section("Section 1")
+    section_1.add("This is a paragraph.")
+    section_1.add("This is another paragraph.")
+    assert (
+        str(section_1) == "# Section 1\nThis is a paragraph.  \nThis is another paragraph.  \n"
+    ), "String representation of section is incorrect."
+    assert section_1.title.text == "Section 1", "Section title is incorrect."
 
 
 def test_document():
@@ -283,6 +438,26 @@ def test_document():
         str(document_1) == "# Document 1\n## Section 1\nThis is a paragraph.  \n"
     ), "String representation of document is incorrect."
 
+def test_add_section():
+    """
+    This function tests the markdown.Document class.
+    """
+    document_1 = markdown.Document("Document 1", filename="document_1.md")
+    document_1.add_section("RAW SECTION")
+    assert (
+        str(document_1) == "# Document 1\n# RAW SECTION\n\n"
+    ), "String representation of document is incorrect."
+
+def test_document_toc():
+    """
+    This function tests the markdown.Document class.
+    """
+    document_1 = markdown.Document("Document 1", filename="document_1.md", table_of_contents=True) # pylint: disable=line-too-long
+    document_1.add_section(markdown.Section(markdown.Header("Section 1", 2)))
+    assert (
+        document_1.get_document() == "# Document 1\n## Table of Contents\n* [Section 1](#section-1)\n## Section 1\n\n" # pylint: disable=line-too-long
+    ), "String representation of document is incorrect."
+
 
 def test_document_save(tmp_path):
     """