Address PR feedback: Add validation, error handling, refactoring, and tests

Co-Authored-By: Joe Moura <joao@crewai.com>

tests/test_custom_human_input.py

@@ -1,5 +1,6 @@
+from unittest.mock import MagicMock, patch
+
 import pytest
-from unittest.mock import patch, MagicMock
 
 from crewai.task import Task
 
@@ -21,3 +22,54 @@ def test_task_custom_human_input_parameter():
     # Verify the parameter was stored correctly
     assert task.ask_human_input == custom_input_func
     assert callable(task.ask_human_input)
+
+
+def test_task_invalid_human_input_parameter():
+    """Test that non-callable input raises validation error."""
+    with pytest.raises(ValueError) as exc_info:
+        Task(
+            description="Test task",
+            expected_output="Test output",
+            human_input=True,
+            ask_human_input="not_a_function"
+        )
+    
+    assert "Input should be callable" in str(exc_info.value)
+
+
+def test_custom_input_function_error_handling():
+    """Test handling of errors in custom input function."""
+    def failing_input(_):
+        raise Exception("API Error")
+    
+    # Create a simplified test for error handling
+    # We'll directly test the error handling in the _handle_human_feedback method
+    
+    # Create a mock agent finish object with a simple output
+    agent_finish = MagicMock()
+    agent_finish.output = "Test output"
+    
+    # Create a mock executor with our failing function
+    executor = MagicMock()
+    executor.ask_human_input_function = failing_input
+    
+    # Set up the default input method mock
+    executor._ask_human_input = MagicMock(return_value="Default input used")
+    
+    # Add the extract method that returns the output directly
+    executor._extract_output_from_agent_finish = MagicMock(return_value="Test output")
+    
+    # Test the error handling by calling the method directly
+    from crewai.agents.crew_agent_executor import CrewAgentExecutor
+    
+    # Capture print output to verify error message
+    with patch('builtins.print') as mock_print:
+        # Call the method we're testing
+        CrewAgentExecutor._handle_human_feedback(executor, agent_finish)
+        
+        # Verify error was printed
+        mock_print.assert_called_once()
+        assert "Error using custom input function" in mock_print.call_args[0][0]
+        
+    # Verify fallback to default method occurred
+    executor._ask_human_input.assert_called_once_with("Test output")