Address PR feedback: improve documentation, add deprecation warning, enhance test coverage

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

tests/test_crewai_alias.py

@@ -1,17 +1,56 @@
 import unittest
 
+
 class TestCrewaiAlias(unittest.TestCase):
-    """Test the Crewai alias for backward compatibility."""
+    """Tests validating the Crewai alias and its backward compatibility.
+    
+    These tests ensure that the Crewai alias works correctly for both
+    import scenarios and practical usage, providing backward compatibility
+    for existing code that uses the 'Crewai' name.
+    """
 
     def test_crewai_alias_import(self):
         """Test that Crewai can be imported from crewai.crew."""
         try:
-            from crewai.crew import Crewai
-            from crewai.crew import Crew
+            from crewai.crew import Crew, Crewai
             
             self.assertEqual(Crewai, Crew)
         except ImportError:
             self.fail("Failed to import Crewai from crewai.crew")
+    
+    def test_crewai_instance_creation(self):
+        """Ensure Crewai can be instantiated just like Crew."""
+        from crewai.crew import Crew, Crewai
+        from crewai.agent import Agent
+        
+        test_agent = Agent(
+            role="Test Agent",
+            goal="Testing",
+            backstory="Created for testing"
+        )
+        
+        crewai_instance = Crewai(agents=[test_agent], tasks=[])
+        crew_instance = Crew(agents=[test_agent], tasks=[])
+        
+        self.assertIsInstance(crewai_instance, Crew)
+        self.assertEqual(type(crewai_instance), type(crew_instance))
+    
+    def test_crewai_deprecation_warning(self):
+        """Test that using Crewai emits a deprecation warning."""
+        import warnings
+        import importlib
+        import crewai.crew
+        
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter("always")
+            importlib.reload(crewai.crew)
+            
+            self.assertTrue(len(w) > 0, "No deprecation warning was captured")
+            self.assertTrue(any(issubclass(warning.category, DeprecationWarning) for warning in w), 
+                           "No DeprecationWarning was found")
+            self.assertTrue(any("Crewai is deprecated" in str(warning.message) for warning in w),
+                           "Warning message doesn't contain expected text")
+
 
 if __name__ == "__main__":
     unittest.main()