Remove introductory text from README and add unit tests for LineCounter functionality

Author: codeperfectplus

README.md

@@ -1,7 +1,3 @@
-Here’s a clean and informative `README.md` for your package **`extliner`**:
-
----
-
 ## 📦 extliner
 
 **extliner** is a lightweight Python package that counts lines in files (with and without empty lines) grouped by file extension — perfect for analyzing codebases or text-heavy directories.

tests/test_linecounter.py

@@ -0,0 +1,81 @@
+import unittest
+import tempfile
+from pathlib import Path
+from extliner.main import LineCounter
+
+
+class TestLineCounter(unittest.TestCase):
+
+    # inbuilt setup and teardown methods to create a temporary directory for testing
+    def setUp(self):
+        self.temp_dir = tempfile.TemporaryDirectory()
+        self.base_path = Path(self.temp_dir.name)
+
+    # it will call the cleanup method of TemporaryDirectory to delete the directory after tests
+    def tearDown(self):
+        self.temp_dir.cleanup()
+
+    def create_file(self, relative_path: str, content: str):
+        file_path = self.base_path / relative_path
+        file_path.parent.mkdir(parents=True, exist_ok=True)
+        file_path.write_text(content, encoding="utf-8")
+
+    def test_single_file_with_and_without_spaces(self):
+        self.create_file("hello.py", "print('Hello')\n\nprint('World')\n")
+
+        counter = LineCounter()
+        result = counter.count_lines(self.base_path)
+
+        self.assertIn(".py", result)
+        self.assertEqual(result[".py"]["with_spaces"], 3)
+        self.assertEqual(result[".py"]["without_spaces"], 2)
+
+    def test_multiple_extensions(self):
+        self.create_file("a.py", "print('a')\n\n")
+        self.create_file("b.js", "console.log('b');\n")
+        self.create_file("c.txt", "\n\ntext\n\n")
+
+        counter = LineCounter()
+        result = counter.count_lines(self.base_path)
+
+        self.assertEqual(result[".py"]["with_spaces"], 2)
+        self.assertEqual(result[".py"]["without_spaces"], 1)
+        self.assertEqual(result[".js"]["with_spaces"], 1)
+        self.assertEqual(result[".js"]["without_spaces"], 1)
+        self.assertEqual(result[".txt"]["with_spaces"], 4)
+        self.assertEqual(result[".txt"]["without_spaces"], 1)
+
+    def test_ignore_extensions(self):
+        self.create_file("a.py", "code\ncode\n")
+        self.create_file("b.txt", "text\ntext\n")
+
+        counter = LineCounter(ignore_extensions=[".txt"])
+        result = counter.count_lines(self.base_path)
+
+        self.assertIn(".py", result)
+        self.assertNotIn(".txt", result)
+
+    def test_no_extension_file(self):
+        self.create_file("README", "line1\nline2\n")
+
+        counter = LineCounter()
+        result = counter.count_lines(self.base_path)
+
+        self.assertIn("NO_EXT", result)
+        self.assertEqual(result["NO_EXT"]["with_spaces"], 2)
+        self.assertEqual(result["NO_EXT"]["without_spaces"], 2)
+
+    def test_to_json_format(self):
+        self.create_file("sample.py", "x = 1\n\ny = 2\n")
+
+        counter = LineCounter()
+        data = counter.count_lines(self.base_path)
+        json_str = counter.to_json(data)
+
+        self.assertTrue(json_str.startswith("{"))
+        self.assertIn('"with_spaces":', json_str)
+        self.assertIn('"without_spaces":', json_str)
+
+
+if __name__ == "__main__":
+    unittest.main()