Fix bundled subbrute import fallback

sublist3r.py

@@ -18,10 +18,29 @@ import json
 from collections import Counter
 
 # external modules
-from subbrute import subbrute
 import dns.resolver
 import requests
 
+
+def load_subbrute_module():
+    """Load the bundled subbrute module even if another package shadows it."""
+    try:
+        from subbrute import subbrute
+        return subbrute
+    except ImportError:
+        module_path = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'subbrute', 'subbrute.py')
+        if sys.version_info[0] >= 3:
+            import importlib.util
+            spec = importlib.util.spec_from_file_location('sublist3r_bundled_subbrute', module_path)
+            module = importlib.util.module_from_spec(spec)
+            spec.loader.exec_module(module)
+            return module
+        import imp
+        return imp.load_source('sublist3r_bundled_subbrute', module_path)
+
+
+subbrute = load_subbrute_module()
+
 # Python 2.x and 3.x compatiablity
 if sys.version > '3':
     import urllib.parse as urlparse

tests/test_subbrute_import.py

@@ -0,0 +1,42 @@
+import os
+import subprocess
+import sys
+import tempfile
+import textwrap
+import unittest
+
+
+class SubbruteImportTest(unittest.TestCase):
+    def test_import_uses_bundled_subbrute_when_external_package_shadows_it(self):
+        repo_root = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+        with tempfile.TemporaryDirectory() as temp_dir:
+            shadow_package = os.path.join(temp_dir, "subbrute")
+            os.mkdir(shadow_package)
+            with open(os.path.join(shadow_package, "__init__.py"), "w", encoding="utf-8") as handle:
+                handle.write("# external package without a subbrute module\n")
+
+            command = textwrap.dedent(
+                """
+                import os
+                import sublist3r
+
+                bundled = os.path.join(os.path.dirname(sublist3r.__file__), "subbrute", "subbrute.py")
+                assert os.path.abspath(sublist3r.subbrute.__file__) == os.path.abspath(bundled)
+                """
+            )
+            env = os.environ.copy()
+            env["PYTHONPATH"] = repo_root
+            result = subprocess.run(
+                [sys.executable, "-c", command],
+                cwd=temp_dir,
+                env=env,
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                text=True,
+            )
+
+        self.assertEqual(result.returncode, 0, result.stderr)
+
+
+if __name__ == "__main__":
+    unittest.main()