Reject backslashes in normalized base URLs

Co-authored-by: Shri Sukhani <shrisukhani@users.noreply.github.com>

Author: cursoragent

hyperbrowser/config.py

@@ -38,6 +38,8 @@ def normalize_base_url(base_url: str) -> str:
             raise HyperbrowserError("base_url must not contain newline characters")
         if any(character.isspace() for character in normalized_base_url):
             raise HyperbrowserError("base_url must not contain whitespace characters")
+        if "\\" in normalized_base_url:
+            raise HyperbrowserError("base_url must not contain backslashes")
 
         parsed_base_url = urlparse(normalized_base_url)
         if (

tests/test_config.py

@@ -218,6 +218,10 @@ def test_client_config_rejects_empty_or_invalid_base_url():
         HyperbrowserError, match="base_url must not contain whitespace characters"
     ):
         ClientConfig(api_key="test-key", base_url="https://example .local")
+    with pytest.raises(
+        HyperbrowserError, match="base_url must not contain backslashes"
+    ):
+        ClientConfig(api_key="test-key", base_url="https://example.local\\api")
 
 
 def test_client_config_normalizes_headers_to_internal_copy():
@@ -333,3 +337,7 @@ def test_client_config_normalize_base_url_validates_and_normalizes():
         HyperbrowserError, match="base_url must not contain whitespace characters"
     ):
         ClientConfig.normalize_base_url("https://example.local/\tapi")
+    with pytest.raises(
+        HyperbrowserError, match="base_url must not contain backslashes"
+    ):
+        ClientConfig.normalize_base_url("https://example.local\\api")

tests/test_url_building.py

@@ -110,6 +110,12 @@ def test_client_build_url_rejects_runtime_invalid_base_url_changes():
         ):
             client._build_url("/session")
 
+        client.config.base_url = "https://example.local\\api"
+        with pytest.raises(
+            HyperbrowserError, match="base_url must not contain backslashes"
+        ):
+            client._build_url("/session")
+
         client.config.base_url = "   "
         with pytest.raises(HyperbrowserError, match="base_url must not be empty"):
             client._build_url("/session")