fix: Solves Issues with Set Function in Component Class and Enhance Input Handling (#4258)

* Enhance Component Input Handling and Add Unit Tests

Enhance component input handling and add unit tests for mixed input scenarios.

* [autofix.ci] apply automated fixes

* fix: handle JSON serialization for lists and dicts in _process_connection_or_parameters

- Updated the _process_connection_or_parameters function to handle lists and dictionaries properly.
- Ensured that each element in a list is checked for serializability and converted to a string if necessary.
- Added logic to convert dictionaries to JSON strings, handling non-serializable contents by converting them to strings.
- This change prevents JSON serialization errors when processing component parameters.

* reverting the changes

* [autofix.ci] apply automated fixes

* Update component.py

updates _process_connection_or_parameters to handles situations where the list is not all component.

Also handles any serialisation isseus caused by _process_connection_or_parameters

* [autofix.ci] apply automated fixes

* Update component.py

update make sure it is not a list str | int | float | bool | type(None)

Serialisation removed

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

src/backend/base/langflow/base/tools/component_tool.py

@@ -47,6 +47,8 @@ def build_description(component: Component, output: Output) -> str:
 
 def _build_output_function(component: Component, output_method: Callable):
     def output_function(*args, **kwargs):
+        # set the component with the arguments
+        # set functionality was updatedto handle list of components and other values separately
         component.set(*args, **kwargs)
         return output_method()
 

src/backend/base/langflow/custom/custom_component/component.py

@@ -442,7 +442,8 @@ class Component(CustomComponent):
 
     def _process_connection_or_parameters(self, key, value) -> None:
         # if value is a list of components, we need to process each component
-        if isinstance(value, list):
+        # Note this update make sure it is not a list str | int | float | bool | type(None)
+        if isinstance(value, list) and not any(isinstance(val, str | int | float | bool | type(None)) for val in value):
             for val in value:
                 self._process_connection_or_parameter(key, val)
         else:

src/backend/tests/unit/custom/component/test_componet_set_functionality.py

@@ -0,0 +1,49 @@
+import pytest
+from langflow.custom import Component
+from langflow.inputs.inputs import MessageTextInput, StrInput
+
+
+@pytest.fixture
+def setup_component():
+    # Create a sample component for testing
+    component = Component()
+    # Define inputs for the component
+    component.inputs = [
+        MessageTextInput(name="list_message_input", is_list=True),  # Input for a mock component
+        StrInput(name="mixed_input"),  # Input for a mixed list
+    ]
+    return component
+
+
+def test_set_with_mixed_list_input(setup_component):
+    component = setup_component
+    # Create a mock component to include in the list
+    mock_component = Component()
+    message_input_1 = "message data1"
+    message_input_2 = "message data2"
+    data = {"mixed_input": [message_input_1, message_input_2], "list_message_input": [message_input_1, mock_component]}
+    component.set(**data)
+
+    # Assert that the mixed input was set correctly
+    assert hasattr(component, "mixed_input")
+    assert len(component.mixed_input) == 2
+    assert component.mixed_input[0] == message_input_1
+    assert component.mixed_input[1] == message_input_2
+    assert component.list_message_input[0] == message_input_1
+    assert component.list_message_input[1] == mock_component
+
+
+def test_set_with_message_text_input_list(setup_component):
+    component = setup_component
+    # Create a list of MessageTextInput instances
+    message_input_1 = "message data1"
+    message_input_2 = "message data2"
+    data = {"mixed_input": [message_input_1, message_input_2], "list_message_input": [message_input_1, message_input_2]}
+    # Set a list containing MessageTextInput instances
+    component.set(**data)
+
+    # Assert that the mixed input was set correctly
+    assert hasattr(component, "mixed_input")
+    assert len(component.list_message_input) == 2
+    assert component.list_message_input[0] == message_input_1
+    assert component.list_message_input[1] == message_input_2