feat: Add unittest coverage

tests/test_adblock.py

@@ -0,0 +1,51 @@
+import pathlib
+import sys
+import unittest
+
+
+ROOT = pathlib.Path(__file__).resolve().parents[1]
+SRC = ROOT / "src"
+if str(SRC) not in sys.path:
+    sys.path.insert(0, str(SRC))
+
+from core.adblock import parse_hosts_text
+
+
+class ParseHostsTextTests(unittest.TestCase):
+    def test_parses_hosts_and_bare_domains_and_deduplicates(self):
+        text = """
+        # comment
+        0.0.0.0 ads.example.com
+        127.0.0.1 tracker.example.com # inline comment
+        plain.example.org
+        ads.example.com
+        EXAMPLE.NET.
+        """
+
+        self.assertEqual(
+            parse_hosts_text(text),
+            [
+                "ads.example.com",
+                "tracker.example.com",
+                "plain.example.org",
+                "example.net",
+            ],
+        )
+
+    def test_skips_invalid_reserved_and_wildcard_entries(self):
+        text = """
+        localhost
+        localhost.localdomain
+        192.168.1.1
+        ::1
+        analytics-*.example.com
+        invalid
+        bad_domain.example
+        host name.example.com
+        """
+
+        self.assertEqual(parse_hosts_text(text), [])
+
+
+if __name__ == "__main__":
+    unittest.main()