fix: surface broken import errors when loading components

Author: JohananOppongAmoateng

src/django_unicorn/components/unicorn_view.py

@@ -1017,8 +1017,15 @@ def _get_component_class(module_name: str, class_name: str) -> type[Component]:
 
                 return component
             except ModuleNotFoundError as e:
-                logger.debug(e)
-                pass
+                # Only silently skip when the module we're looking for simply doesn't
+                # exist.  If a *different* module is missing it means the component file
+                # was found and started executing but contains a broken import - that
+                # error should be surfaced rather than swallowed.
+                if e.name is None or module_name == e.name or module_name.startswith(e.name + "."):
+                    logger.debug(e)
+                else:
+                    message = f"The component module '{module_name}' could not be loaded: {e}"
+                    raise ComponentModuleLoadError(message, locations=locations) from e
             except AttributeError as e:
                 logger.debug(e)
                 attribute_exception = e

tests/views/fake_components_with_broken_import.py

@@ -0,0 +1,7 @@
+from nonexistent_package_xyz_abc import SomeClass  # noqa: F401  # type: ignore[import]
+
+from django_unicorn.components import UnicornView
+
+
+class FakeComponentWithBrokenImport(UnicornView):
+    template_name = "templates/test_component.html"

tests/views/message/test_message.py

@@ -156,6 +156,31 @@ def test_message_component_class_with_attribute_error(client):
         )
 
     assert e.value.__cause__
+    # The original AttributeError should be included in the message so the
+    # developer can see what actually went wrong, not just that loading failed.
+    assert "not_a_valid_attribute" in e.exconly()
+
+
+def test_message_component_module_with_broken_import(client):
+    """A component that exists but contains a broken import should surface the
+    underlying ModuleNotFoundError rather than masking it with a generic
+    "component module could not be loaded" message (issue #380)."""
+    data = {
+        "data": {},
+        "meta": "DVVk97cx",
+        "id": str(uuid4()),
+        "epoch": time.time(),
+    }
+
+    with pytest.raises(ComponentModuleLoadError) as e:
+        post_json(
+            client,
+            data,
+            url="/message/tests.views.fake_components_with_broken_import.FakeComponentWithBrokenImport",
+        )
+
+    assert e.value.__cause__
+    assert "nonexistent_package_xyz_abc" in e.exconly()
 
 
 def test_message_component_with_dash(client):