Address PR feedback: Add type hints, use Color enum, and enhance tests

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

tests/utilities/test_logger.py

@@ -1,22 +1,29 @@
 import sys
 import unittest
+import threading
 from unittest.mock import patch
 from io import StringIO
+import pytest
 
 from crewai.utilities.logger import Logger
 
 
 class TestLogger(unittest.TestCase):
+    """Test suite for the Logger class."""
+    
     def setUp(self):
+        """Set up test environment before each test."""
         self.logger = Logger(verbose=True)
         self.output = StringIO()
         self.old_stdout = sys.stdout
         sys.stdout = self.output
 
     def tearDown(self):
+        """Clean up test environment after each test."""
         sys.stdout = self.old_stdout
 
     def test_log_in_sync_context(self):
+        """Test logging in a regular synchronous context."""
         self.logger.log("info", "Test message")
         output = self.output.getvalue()
         self.assertIn("[INFO]: Test message", output)
@@ -24,12 +31,52 @@ class TestLogger(unittest.TestCase):
 
     @patch('sys.stdout.flush')
     def test_stdout_is_flushed(self, mock_flush):
+        """Test that stdout is properly flushed after writing."""
         self.logger.log("info", "Test message")
         mock_flush.assert_called_once()
+    
+    @pytest.mark.parametrize("log_level,message", [
+        ("info", "Info message"),
+        ("error", "Error message"),
+        ("warning", "Warning message"),
+        ("debug", "Debug message")
+    ])
+    def test_multiple_log_levels(self, log_level, message):
+        """Test logging with different log levels."""
+        self.logger.log(log_level, message)
+        output = self.output.getvalue()
+        self.assertIn(f"[{log_level.upper()}]: {message}", output)
+    
+    def test_thread_safety(self):
+        """Test that logger is thread-safe."""
+        messages = []
+        for i in range(10):
+            messages.append(f"Message {i}")
+        
+        threads = []
+        for message in messages:
+            thread = threading.Thread(
+                target=lambda msg: self.logger.log("info", msg),
+                args=(message,)
+            )
+            threads.append(thread)
+        
+        for thread in threads:
+            thread.start()
+        
+        for thread in threads:
+            thread.join()
+        
+        output = self.output.getvalue()
+        for message in messages:
+            self.assertIn(message, output)
 
 
 class TestFastAPICompatibility(unittest.TestCase):
+    """Test compatibility with FastAPI."""
+    
     def test_import_in_fastapi(self):
+        """Test that logger can be imported in a FastAPI context."""
         try:
             import fastapi
             from crewai.utilities.logger import Logger