chore: import upstream snapshot with attribution

test/test_imports.py

@@ -0,0 +1,41 @@
+# SPDX-FileCopyrightText: 2022-present deepset GmbH <info@deepset.ai>
+#
+# SPDX-License-Identifier: Apache-2.0
+
+import sys
+from unittest.mock import patch
+
+from haystack.lazy_imports import LazyImport
+
+
+def test_lazy_importer_avoids_importing_unused_modules():
+    # Save the original state of the module if it exists
+    original_imported = sys.modules.get("haystack.components.generators.chat.azure")
+
+    with patch.dict(sys.modules):
+        # Remove the module from sys.modules if it was already imported
+        if original_imported:
+            del sys.modules["haystack.components.generators.chat.azure"]
+
+        from haystack.components.generators.chat import OpenAIChatGenerator  # Import the intended class # noqa: F401
+
+        assert "haystack.components.generators.chat.openai" in sys.modules.keys()
+        assert "haystack.components.generators.chat.azure" not in sys.modules.keys()
+
+    # Restore the module if it was previously imported (preserves test isolation)
+    if original_imported:
+        sys.modules["haystack.components.generators.chat.azure"] = original_imported
+
+
+def test_import_error_is_suppressed_and_deferred():
+    with LazyImport() as lazy_import:
+        import a_module  # noqa: F401
+
+    assert lazy_import._deferred is not None
+    exc_value, message = lazy_import._deferred
+    assert isinstance(exc_value, ImportError)
+    expected_message = (
+        "Haystack failed to import the optional dependency 'a_module'. Try 'pip install a_module'. "
+        "Original error: No module named 'a_module'"
+    )
+    assert expected_message in message