gh-131178: add unittest for turtledemo

Author: fatelei

Lib/test/test_turtledemo.py

@@ -0,0 +1,194 @@
+"""
+Test command line interface for turtledemo module.
+
+This test suite validates the CLI functionality of the turtledemo module,
+which provides a GUI-based demo viewer for turtle graphics examples.
+"""
+import sys
+import os
+import importlib.util
+
+
+class SimpleTest:
+    """Simple test framework to avoid compatibility issues."""
+    def __init__(self):
+        self.passed = 0
+        self.failed = 0
+        
+    def assert_true(self, condition, msg=""):
+        if condition:
+            self.passed += 1
+            print(f"✓ {msg}")
+        else:
+            self.failed += 1
+            print(f"✗ {msg}")
+            
+    def assert_equal(self, a, b, msg=""):
+        if a == b:
+            self.passed += 1
+            print(f"✓ {msg}")
+        else:
+            self.failed += 1
+            print(f"✗ {msg}: {a} != {b}")
+            
+    def assert_in(self, item, container, msg=""):
+        if item in container:
+            self.passed += 1
+            print(f"✓ {msg}")
+        else:
+            self.failed += 1
+            print(f"✗ {msg}: {item} not in {container}")
+            
+    def assert_is_instance(self, obj, expected_type, msg=""):
+        if isinstance(obj, expected_type):
+            self.passed += 1
+            print(f"✓ {msg}")
+        else:
+            self.failed += 1
+            print(f"✗ {msg}: {type(obj)} != {expected_type}")
+            
+    def assert_has_attr(self, obj, attr, msg=""):
+        if hasattr(obj, attr):
+            self.passed += 1
+            print(f"✓ {msg}")
+        else:
+            self.failed += 1
+            print(f"✗ {msg}: {attr} not found")
+            
+    def summary(self):
+        total = self.passed + self.failed
+        print(f"\nTest Summary: {self.passed}/{total} passed, {self.failed} failed")
+        return self.failed == 0
+
+
+def test_turtledemo_cli():
+    """Test command line interface for turtledemo module."""
+    test = SimpleTest()
+    
+    print("Testing turtledemo command line interface...")
+    
+    # Test 1: Check turtledemo directory structure
+    demo_dir = os.path.join(os.path.dirname(__file__), '..', 'turtledemo')
+    test.assert_true(os.path.exists(demo_dir), "turtledemo directory exists")
+    test.assert_true(os.path.isdir(demo_dir), "turtledemo is a directory")
+    
+    # Test 2: Check __main__.py exists
+    main_file = os.path.join(demo_dir, '__main__.py')
+    test.assert_true(os.path.exists(main_file), "__main__.py exists")
+    
+    # Test 3: Check demo files exist        
+    if os.path.exists(demo_dir):
+        demo_files = [f for f in os.listdir(demo_dir) 
+                     if f.endswith('.py') and not f.startswith('_')]
+        test.assert_true(len(demo_files) > 0, f"found {len(demo_files)} demo files")
+        
+        # Check for known demo files
+        expected_demos = ['bytedesign.py', 'chaos.py', 'clock.py', 'colormixer.py', 'forest.py']
+        for demo in expected_demos:
+            test.assert_in(demo, demo_files, f"demo file {demo} exists")
+    
+    # Test 4: Test module import (may fail due to dependencies)
+    try:
+        spec = importlib.util.spec_from_file_location("turtledemo", 
+                                                     os.path.join(demo_dir, '__init__.py'))
+        if spec and spec.loader:
+            turtledemo = importlib.util.module_from_spec(spec)
+            spec.loader.exec_module(turtledemo)
+            test.assert_true(True, "turtledemo module imported successfully")
+        else:
+            test.assert_true(False, "could not create spec for turtledemo")
+    except Exception as e:
+        test.assert_true(False, f"turtledemo import failed: {e}")
+    
+    # Test 5: Test __main__ module structure
+    try:
+        main_file = os.path.join(demo_dir, '__main__.py')
+        with open(main_file, 'r') as f:
+            content = f.read()
+            
+        # Check for key functions and classes
+        test.assert_in('def main():', content, "main function defined")
+        test.assert_in('class DemoWindow', content, "DemoWindow class defined")
+        test.assert_in('def getExampleEntries():', content, "getExampleEntries function defined")
+        test.assert_in('if __name__ == \'__main__\':', content, "__main__ guard present")
+        
+        # Check for imports
+        test.assert_in('import sys', content, "sys import present")
+        test.assert_in('import os', content, "os import present")
+        test.assert_in('from tkinter import', content, "tkinter import present")
+        
+    except Exception as e:
+        test.assert_true(False, f"failed to read __main__.py: {e}")
+    
+    # Test 6: Test individual demo files structure
+    demo_files_to_check = ['bytedesign.py', 'chaos.py', 'clock.py']
+    for demo_file in demo_files_to_check:
+        demo_path = os.path.join(demo_dir, demo_file)
+        if os.path.exists(demo_path):
+            try:
+                with open(demo_path, 'r') as f:
+                    content = f.read()
+                test.assert_in('def main():', content, f"{demo_file} has main function")
+                has_main_guard = ('if __name__ == \'__main__\':' in content or 
+                                  'if __name__ == "__main__":' in content)
+                test.assert_true(has_main_guard, f"{demo_file} has __main__ guard")
+            except Exception as e:
+                test.assert_true(False, f"failed to read {demo_file}: {e}")
+    
+    # Test 7: Check configuration files
+    config_file = os.path.join(demo_dir, 'turtle.cfg')
+    test.assert_true(os.path.exists(config_file), "turtle.cfg exists")
+    
+    # Test 8: Test command line execution simulation
+    try:
+        # Simulate what happens when running: python -m turtledemo
+        main_file = os.path.join(demo_dir, '__main__.py')
+        
+        # Read the file to check it's syntactically valid Python
+        with open(main_file, 'r') as f:
+            content = f.read()
+        
+        # Try to compile it
+        compile(content, main_file, 'exec')
+        test.assert_true(True, "__main__.py is valid Python code")
+        
+    except SyntaxError as e:
+        test.assert_true(False, f"__main__.py has syntax error: {e}")
+    except Exception as e:
+        test.assert_true(False, f"failed to validate __main__.py: {e}")
+    
+    # Test 9: Check for documentation strings
+    try:
+        main_file = os.path.join(demo_dir, '__main__.py')
+        with open(main_file, 'r') as f:
+            content = f.read()
+        
+        # Check for module docstring
+        test.assert_true(content.startswith('"""') or content.startswith("'''"), 
+                        "__main__.py has module docstring")
+        
+        # Check for function docstrings
+        test.assert_in('"""', content, "contains docstrings")
+        
+    except Exception as e:
+        test.assert_true(False, f"failed to check docstrings: {e}")
+    
+    # Test 10: Test CLI entry point
+    try:
+        # The CLI entry point should be the main() function in __main__.py
+        main_file = os.path.join(demo_dir, '__main__.py')
+        with open(main_file, 'r') as f:
+            content = f.read()
+        
+        # Check that main() is called when run as script
+        test.assert_in('main()', content, "main() is called in __main__")
+        
+    except Exception as e:
+        test.assert_true(False, f"failed to check CLI entry point: {e}")
+    
+    return test.summary()
+
+
+if __name__ == '__main__':
+    success = test_turtledemo_cli()
+    sys.exit(0 if success else 1)