Add guard tests for display helper usage

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

Author: cursoragent

tests/test_display_helper_usage.py

@@ -0,0 +1,73 @@
+import ast
+from pathlib import Path
+
+
+HYPERBROWSER_ROOT = Path(__file__).resolve().parents[1] / "hyperbrowser"
+ALLOWED_NORMALIZE_DISPLAY_CALL_FILES = {
+    Path("display_utils.py"),
+    Path("client/managers/response_utils.py"),
+    Path("transport/base.py"),
+}
+
+
+def _python_files() -> list[Path]:
+    return sorted(HYPERBROWSER_ROOT.rglob("*.py"))
+
+
+def _collect_normalize_display_calls(module: ast.AST) -> list[int]:
+    matches: list[int] = []
+    for node in ast.walk(module):
+        if not isinstance(node, ast.Call):
+            continue
+        if not isinstance(node.func, ast.Name):
+            continue
+        if node.func.id != "normalize_display_text":
+            continue
+        matches.append(node.lineno)
+    return matches
+
+
+def _collect_format_key_calls(module: ast.AST) -> list[int]:
+    matches: list[int] = []
+    for node in ast.walk(module):
+        if not isinstance(node, ast.Call):
+            continue
+        if not isinstance(node.func, ast.Name):
+            continue
+        if node.func.id != "format_string_key_for_error":
+            continue
+        matches.append(node.lineno)
+    return matches
+
+
+def test_normalize_display_text_usage_is_centralized():
+    violations: list[str] = []
+
+    for path in _python_files():
+        relative_path = path.relative_to(HYPERBROWSER_ROOT)
+        source = path.read_text(encoding="utf-8")
+        module = ast.parse(source, filename=str(relative_path))
+        normalize_calls = _collect_normalize_display_calls(module)
+        if not normalize_calls:
+            continue
+        if relative_path in ALLOWED_NORMALIZE_DISPLAY_CALL_FILES:
+            continue
+        for line in normalize_calls:
+            violations.append(f"{relative_path}:{line}")
+
+    assert violations == []
+
+
+def test_key_formatting_helper_is_used_outside_display_module():
+    helper_usage_files: set[Path] = set()
+
+    for path in _python_files():
+        relative_path = path.relative_to(HYPERBROWSER_ROOT)
+        if relative_path == Path("display_utils.py"):
+            continue
+        source = path.read_text(encoding="utf-8")
+        module = ast.parse(source, filename=str(relative_path))
+        if _collect_format_key_calls(module):
+            helper_usage_files.add(relative_path)
+
+    assert helper_usage_files != set()