diff --git a/src/test_sort.py b/src/test_sort.py
new file mode 100644
index 0000000..5f61751
--- /dev/null
+++ b/src/test_sort.py
@@ -0,0 +1,50 @@
+import pytest
+from src.sort import bubble_sort
+
+def test_bubble_sort_empty_list():
+    assert bubble_sort([]) == []
+
+def test_bubble_sort_single_element():
+    assert bubble_sort([1]) == [1]
+
+def test_bubble_sort_sorted_list():
+    assert bubble_sort([1, 2, 3, 4, 5]) == [1, 2, 3, 4, 5]
+
+def test_bubble_sort_reverse_sorted():
+    assert bubble_sort([5, 4, 3, 2, 1]) == [1, 2, 3, 4, 5]
+
+def test_bubble_sort_duplicates():
+    assert bubble_sort([3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]) == [1, 1, 2, 3, 3, 4, 5, 5, 5, 6, 9]
+
+def test_bubble_sort_negative_numbers():
+    assert bubble_sort([-3, -1, -4, -1, -5]) == [-5, -4, -3, -1, -1]
+
+def test_bubble_sort_mixed_numbers():
+    assert bubble_sort([-2, 3, 0, -1, 4]) == [-2, -1, 0, 3, 4]
+
+def test_bubble_sort_float_numbers():
+    assert bubble_sort([3.14, 2.71, 1.41, 1.73]) == [1.41, 1.73, 2.71, 3.14]
+
+def test_bubble_sort_strings():
+    assert bubble_sort(['banana', 'apple', 'cherry']) == ['apple', 'banana', 'cherry']
+
+def test_bubble_sort_large_list():
+    input_list = list(range(1000, 0, -1))  # 1000 to 1
+    expected = list(range(1, 1001))  # 1 to 1000
+    assert bubble_sort(input_list) == expected
+
+def test_bubble_sort_none_elements():
+    with pytest.raises(TypeError):
+        bubble_sort([1, None, 3])
+
+def test_bubble_sort_mixed_types():
+    with pytest.raises(TypeError):
+        bubble_sort([1, "2", 3])
+
+def test_bubble_sort_invalid_input():
+    with pytest.raises(TypeError):
+        bubble_sort(None)
+    with pytest.raises(TypeError):
+        bubble_sort(123)
+    with pytest.raises(TypeError):
+        bubble_sort("string")