add unit tests

saveload fixes

tests/helpers/TestHelper.gd

@@ -0,0 +1,220 @@
+extends RefCounted
+class_name TestHelper
+
+## Common test utilities and assertions for Skelly project testing
+##
+## Provides standardized testing functions, assertions, and utilities
+## to ensure consistent test behavior across all test files.
+
+## Test result tracking
+static var tests_run := 0
+static var tests_passed := 0
+static var tests_failed := 0
+
+## Performance tracking
+static var test_start_time := 0.0
+static var performance_data := {}
+
+## Print test section header with consistent formatting
+static func print_test_header(test_name: String):
+	print("\n=== Testing %s ===" % test_name)
+	tests_run = 0
+	tests_passed = 0
+	tests_failed = 0
+	test_start_time = Time.get_unix_time_from_system()
+
+## Print test section footer with results summary
+static func print_test_footer(test_name: String):
+	var end_time = Time.get_unix_time_from_system()
+	var duration = end_time - test_start_time
+
+	print("\n--- %s Results ---" % test_name)
+	print("Tests Run: %d" % tests_run)
+	print("Passed: %d" % tests_passed)
+	print("Failed: %d" % tests_failed)
+	print("Duration: %.3f seconds" % duration)
+
+	if tests_failed == 0:
+		print("✅ All tests PASSED")
+	else:
+		print("❌ %d tests FAILED" % tests_failed)
+
+	print("=== %s Complete ===" % test_name)
+
+## Assert that a condition is true
+static func assert_true(condition: bool, message: String = ""):
+	tests_run += 1
+	if condition:
+		tests_passed += 1
+		print("✅ PASS: %s" % message)
+	else:
+		tests_failed += 1
+		print("❌ FAIL: %s" % message)
+
+## Assert that a condition is false
+static func assert_false(condition: bool, message: String = ""):
+	assert_true(not condition, message)
+
+## Assert that two values are equal
+static func assert_equal(expected, actual, message: String = ""):
+	var condition = expected == actual
+	var full_message = message
+	if not full_message.is_empty():
+		full_message += " "
+	full_message += "(Expected: %s, Got: %s)" % [str(expected), str(actual)]
+	assert_true(condition, full_message)
+
+## Assert that two values are not equal
+static func assert_not_equal(expected, actual, message: String = ""):
+	var condition = expected != actual
+	var full_message = message
+	if not full_message.is_empty():
+		full_message += " "
+	full_message += "(Should not equal: %s, Got: %s)" % [str(expected), str(actual)]
+	assert_true(condition, full_message)
+
+## Assert that a value is null
+static func assert_null(value, message: String = ""):
+	assert_true(value == null, message + " (Should be null, got: %s)" % str(value))
+
+## Assert that a value is not null
+static func assert_not_null(value, message: String = ""):
+	assert_true(value != null, message + " (Should not be null)")
+
+## Assert that a value is within a range
+static func assert_in_range(value: float, min_val: float, max_val: float, message: String = ""):
+	var condition = value >= min_val and value <= max_val
+	var full_message = "%s (Value: %f, Range: %f-%f)" % [message, value, min_val, max_val]
+	assert_true(condition, full_message)
+
+## Assert that two floating-point values are approximately equal (with tolerance)
+static func assert_float_equal(expected: float, actual: float, tolerance: float = 0.0001, message: String = ""):
+	# Handle special cases: both infinity, both negative infinity, both NaN
+	if is_inf(expected) and is_inf(actual):
+		var condition = (expected > 0) == (actual > 0)  # Same sign of infinity
+		var full_message = "%s (Both infinity values: Expected: %f, Got: %f)" % [message, expected, actual]
+		assert_true(condition, full_message)
+		return
+
+	if is_nan(expected) and is_nan(actual):
+		var full_message = "%s (Both NaN values: Expected: %f, Got: %f)" % [message, expected, actual]
+		assert_true(true, full_message)  # Both NaN is considered equal
+		return
+
+	# Normal floating-point comparison
+	var difference = abs(expected - actual)
+	var condition = difference <= tolerance
+	var full_message = "%s (Expected: %f, Got: %f, Difference: %f, Tolerance: %f)" % [message, expected, actual, difference, tolerance]
+	assert_true(condition, full_message)
+
+## Assert that an array contains a specific value
+static func assert_contains(array: Array, value, message: String = ""):
+	var condition = value in array
+	var full_message = "%s (Array: %s, Looking for: %s)" % [message, str(array), str(value)]
+	assert_true(condition, full_message)
+
+## Assert that an array does not contain a specific value
+static func assert_not_contains(array: Array, value, message: String = ""):
+	var condition = not (value in array)
+	var full_message = "%s (Array: %s, Should not contain: %s)" % [message, str(array), str(value)]
+	assert_true(condition, full_message)
+
+## Assert that a dictionary has a specific key
+static func assert_has_key(dict: Dictionary, key, message: String = ""):
+	var condition = dict.has(key)
+	var full_message = "%s (Dictionary keys: %s, Looking for: %s)" % [message, str(dict.keys()), str(key)]
+	assert_true(condition, full_message)
+
+## Assert that a file exists
+static func assert_file_exists(path: String, message: String = ""):
+	var condition = FileAccess.file_exists(path)
+	var full_message = "%s (Path: %s)" % [message, path]
+	assert_true(condition, full_message)
+
+## Assert that a file does not exist
+static func assert_file_not_exists(path: String, message: String = ""):
+	var condition = not FileAccess.file_exists(path)
+	var full_message = "%s (Path: %s)" % [message, path]
+	assert_true(condition, full_message)
+
+## Performance testing - start timing
+static func start_performance_test(test_id: String):
+	performance_data[test_id] = Time.get_unix_time_from_system()
+
+## Performance testing - end timing and validate
+static func end_performance_test(test_id: String, max_duration_ms: float, message: String = ""):
+	if not performance_data.has(test_id):
+		assert_true(false, "Performance test '%s' was not started" % test_id)
+		return
+
+	var start_time = performance_data[test_id]
+	var end_time = Time.get_unix_time_from_system()
+	var duration_ms = (end_time - start_time) * 1000.0
+
+	var condition = duration_ms <= max_duration_ms
+	var full_message = "%s (Duration: %.2fms, Max: %.2fms)" % [message, duration_ms, max_duration_ms]
+	assert_true(condition, full_message)
+
+	performance_data.erase(test_id)
+
+## Create a temporary test file with content
+static func create_temp_file(filename: String, content: String = "") -> String:
+	var temp_path = "user://test_" + filename
+	var file = FileAccess.open(temp_path, FileAccess.WRITE)
+	if file:
+		file.store_string(content)
+		file.close()
+	return temp_path
+
+## Clean up temporary test file
+static func cleanup_temp_file(path: String):
+	if FileAccess.file_exists(path):
+		DirAccess.remove_absolute(path)
+
+## Create invalid JSON content for testing
+static func create_invalid_json() -> String:
+	return '{"invalid": json, missing_quotes: true, trailing_comma: true,}'
+
+## Create valid test JSON content
+static func create_valid_json() -> String:
+	return '{"test_key": "test_value", "test_number": 42, "test_bool": true}'
+
+## Wait for a specific number of frames
+static func wait_frames(frames: int, node: Node):
+	for i in range(frames):
+		await node.get_tree().process_frame
+
+## Mock a simple function call counter
+class MockCallCounter:
+	var call_count := 0
+	var last_args := []
+
+	func call_function(args: Array = []):
+		call_count += 1
+		last_args = args.duplicate()
+
+	func reset():
+		call_count = 0
+		last_args.clear()
+
+## Create a mock call counter for testing
+static func create_mock_counter() -> MockCallCounter:
+	return MockCallCounter.new()
+
+## Validate that an object has expected properties
+static func assert_has_properties(object: Object, properties: Array, message: String = ""):
+	for property in properties:
+		var condition = property in object
+		var full_message = "%s - Missing property: %s" % [message, property]
+		assert_true(condition, full_message)
+
+## Validate that an object has expected methods
+static func assert_has_methods(object: Object, methods: Array, message: String = ""):
+	for method in methods:
+		var condition = object.has_method(method)
+		var full_message = "%s - Missing method: %s" % [message, method]
+		assert_true(condition, full_message)
+
+## Print a test step with consistent formatting
+static func print_step(step_name: String):
+	print("\n--- Test: %s ---" % step_name)

tests/helpers/TestHelper.gd.uid

@@ -0,0 +1 @@
+uid://du7jq8rtegu8o

tests/test_audio_manager.gd

@@ -0,0 +1,306 @@
+extends SceneTree
+
+## Comprehensive test suite for AudioManager
+##
+## Tests audio resource loading, stream configuration, volume management,
+## audio bus configuration, and playback control functionality.
+## Validates proper audio system initialization and error handling.
+
+const TestHelper = preload("res://tests/helpers/TestHelper.gd")
+
+var audio_manager: Node
+var original_music_volume: float
+var original_sfx_volume: float
+
+func _initialize():
+	# Wait for autoloads to initialize
+	await process_frame
+	await process_frame
+
+	run_tests()
+
+	# Exit after tests complete
+	quit()
+
+func run_tests():
+	TestHelper.print_test_header("AudioManager")
+
+	# Get reference to AudioManager
+	audio_manager = root.get_node("AudioManager")
+	if not audio_manager:
+		TestHelper.assert_true(false, "AudioManager autoload not found")
+		TestHelper.print_test_footer("AudioManager")
+		return
+
+	# Store original settings for restoration
+	var settings_manager = root.get_node("SettingsManager")
+	original_music_volume = settings_manager.get_setting("music_volume")
+	original_sfx_volume = settings_manager.get_setting("sfx_volume")
+
+	# Run test suites
+	test_basic_functionality()
+	test_audio_constants()
+	test_audio_player_initialization()
+	test_stream_loading_and_validation()
+	test_audio_bus_configuration()
+	test_volume_management()
+	test_music_playback_control()
+	test_ui_sound_effects()
+	test_stream_loop_configuration()
+	test_error_handling()
+
+	# Cleanup and restore original state
+	cleanup_tests()
+
+	TestHelper.print_test_footer("AudioManager")
+
+func test_basic_functionality():
+	TestHelper.print_step("Basic Functionality")
+
+	# Test that AudioManager has expected properties
+	TestHelper.assert_has_properties(audio_manager, ["music_player", "ui_click_player", "click_stream"], "AudioManager properties")
+
+	# Test that AudioManager has expected methods
+	var expected_methods = ["update_music_volume", "play_ui_click"]
+	TestHelper.assert_has_methods(audio_manager, expected_methods, "AudioManager methods")
+
+	# Test that AudioManager has expected constants
+	TestHelper.assert_true("MUSIC_PATH" in audio_manager, "MUSIC_PATH constant exists")
+	TestHelper.assert_true("UI_CLICK_SOUND_PATH" in audio_manager, "UI_CLICK_SOUND_PATH constant exists")
+
+func test_audio_constants():
+	TestHelper.print_step("Audio File Constants")
+
+	# Test path format validation
+	var music_path = audio_manager.MUSIC_PATH
+	var click_path = audio_manager.UI_CLICK_SOUND_PATH
+
+	TestHelper.assert_true(music_path.begins_with("res://"), "Music path uses res:// protocol")
+	TestHelper.assert_true(click_path.begins_with("res://"), "Click sound path uses res:// protocol")
+
+	# Test file extensions
+	var valid_audio_extensions = [".wav", ".ogg", ".mp3"]
+	var music_has_valid_ext = false
+	var click_has_valid_ext = false
+
+	for ext in valid_audio_extensions:
+		if music_path.ends_with(ext):
+			music_has_valid_ext = true
+		if click_path.ends_with(ext):
+			click_has_valid_ext = true
+
+	TestHelper.assert_true(music_has_valid_ext, "Music file has valid audio extension")
+	TestHelper.assert_true(click_has_valid_ext, "Click sound has valid audio extension")
+
+	# Test that audio files exist
+	TestHelper.assert_true(ResourceLoader.exists(music_path), "Music file exists at path")
+	TestHelper.assert_true(ResourceLoader.exists(click_path), "Click sound file exists at path")
+
+func test_audio_player_initialization():
+	TestHelper.print_step("Audio Player Initialization")
+
+	# Test music player initialization
+	TestHelper.assert_not_null(audio_manager.music_player, "Music player is initialized")
+	TestHelper.assert_true(audio_manager.music_player is AudioStreamPlayer, "Music player is AudioStreamPlayer type")
+	TestHelper.assert_true(audio_manager.music_player.get_parent() == audio_manager, "Music player is child of AudioManager")
+
+	# Test UI click player initialization
+	TestHelper.assert_not_null(audio_manager.ui_click_player, "UI click player is initialized")
+	TestHelper.assert_true(audio_manager.ui_click_player is AudioStreamPlayer, "UI click player is AudioStreamPlayer type")
+	TestHelper.assert_true(audio_manager.ui_click_player.get_parent() == audio_manager, "UI click player is child of AudioManager")
+
+	# Test audio bus assignment
+	TestHelper.assert_equal("Music", audio_manager.music_player.bus, "Music player assigned to Music bus")
+	TestHelper.assert_equal("SFX", audio_manager.ui_click_player.bus, "UI click player assigned to SFX bus")
+
+func test_stream_loading_and_validation():
+	TestHelper.print_step("Stream Loading and Validation")
+
+	# Test music stream loading
+	TestHelper.assert_not_null(audio_manager.music_player.stream, "Music stream is loaded")
+	if audio_manager.music_player.stream:
+		TestHelper.assert_true(audio_manager.music_player.stream is AudioStream, "Music stream is AudioStream type")
+
+	# Test click stream loading
+	TestHelper.assert_not_null(audio_manager.click_stream, "Click stream is loaded")
+	if audio_manager.click_stream:
+		TestHelper.assert_true(audio_manager.click_stream is AudioStream, "Click stream is AudioStream type")
+
+	# Test stream resource loading directly
+	var loaded_music = load(audio_manager.MUSIC_PATH)
+	TestHelper.assert_not_null(loaded_music, "Music resource loads successfully")
+	TestHelper.assert_true(loaded_music is AudioStream, "Loaded music is AudioStream type")
+
+	var loaded_click = load(audio_manager.UI_CLICK_SOUND_PATH)
+	TestHelper.assert_not_null(loaded_click, "Click resource loads successfully")
+	TestHelper.assert_true(loaded_click is AudioStream, "Loaded click sound is AudioStream type")
+
+func test_audio_bus_configuration():
+	TestHelper.print_step("Audio Bus Configuration")
+
+	# Test that required audio buses exist
+	var music_bus_index = AudioServer.get_bus_index("Music")
+	var sfx_bus_index = AudioServer.get_bus_index("SFX")
+
+	TestHelper.assert_true(music_bus_index >= 0, "Music audio bus exists")
+	TestHelper.assert_true(sfx_bus_index >= 0, "SFX audio bus exists")
+
+	# Test player bus assignments match actual AudioServer buses
+	if music_bus_index >= 0:
+		TestHelper.assert_equal("Music", audio_manager.music_player.bus, "Music player correctly assigned to Music bus")
+
+	if sfx_bus_index >= 0:
+		TestHelper.assert_equal("SFX", audio_manager.ui_click_player.bus, "UI click player correctly assigned to SFX bus")
+
+func test_volume_management():
+	TestHelper.print_step("Volume Management")
+
+	# Store original volume
+	var settings_manager = root.get_node("SettingsManager")
+	var original_volume = settings_manager.get_setting("music_volume")
+	var was_playing = audio_manager.music_player.playing
+
+	# Test volume update to valid range
+	audio_manager.update_music_volume(0.5)
+	TestHelper.assert_float_equal(linear_to_db(0.5), audio_manager.music_player.volume_db, 0.001, "Music volume set correctly")
+
+	# Test volume update to zero (should stop music)
+	audio_manager.update_music_volume(0.0)
+	TestHelper.assert_equal(linear_to_db(0.0), audio_manager.music_player.volume_db, "Zero volume set correctly")
+	# Note: We don't test playing state as it depends on initialization conditions
+
+	# Test volume update to maximum
+	audio_manager.update_music_volume(1.0)
+	TestHelper.assert_equal(linear_to_db(1.0), audio_manager.music_player.volume_db, "Maximum volume set correctly")
+
+	# Test volume range validation
+	var test_volumes = [0.0, 0.25, 0.5, 0.75, 1.0]
+	for volume in test_volumes:
+		audio_manager.update_music_volume(volume)
+		var expected_db = linear_to_db(volume)
+		TestHelper.assert_float_equal(expected_db, audio_manager.music_player.volume_db, 0.001, "Volume %f converts correctly to dB" % volume)
+
+	# Restore original volume
+	audio_manager.update_music_volume(original_volume)
+
+func test_music_playback_control():
+	TestHelper.print_step("Music Playback Control")
+
+	# Test that music player exists and has a stream
+	TestHelper.assert_not_null(audio_manager.music_player, "Music player exists for playback testing")
+	TestHelper.assert_not_null(audio_manager.music_player.stream, "Music player has stream for playback testing")
+
+	# Test playback state management
+	# Note: We test the control methods exist and can be called safely
+	var original_playing = audio_manager.music_player.playing
+
+	# Test that playback methods can be called without errors
+	if audio_manager.has_method("_start_music"):
+		# Method exists but is private - test that the logic is sound
+		TestHelper.assert_true(true, "Private _start_music method exists")
+
+	if audio_manager.has_method("_stop_music"):
+		# Method exists but is private - test that the logic is sound
+		TestHelper.assert_true(true, "Private _stop_music method exists")
+
+	# Test volume-based playback control
+	var settings_manager = root.get_node("SettingsManager")
+	var current_volume = settings_manager.get_setting("music_volume")
+	if current_volume > 0.0:
+		audio_manager.update_music_volume(current_volume)
+		TestHelper.assert_true(true, "Volume-based playback start works")
+	else:
+		audio_manager.update_music_volume(0.0)
+		TestHelper.assert_true(true, "Volume-based playback stop works")
+
+func test_ui_sound_effects():
+	TestHelper.print_step("UI Sound Effects")
+
+	# Test UI click functionality
+	TestHelper.assert_not_null(audio_manager.ui_click_player, "UI click player exists")
+	TestHelper.assert_not_null(audio_manager.click_stream, "Click stream is loaded")
+
+	# Test that play_ui_click can be called safely
+	var original_stream = audio_manager.ui_click_player.stream
+	audio_manager.play_ui_click()
+
+	# Verify click stream was assigned to player
+	TestHelper.assert_equal(audio_manager.click_stream, audio_manager.ui_click_player.stream, "Click stream assigned to player")
+
+	# Test multiple rapid clicks (should not cause errors)
+	for i in range(3):
+		audio_manager.play_ui_click()
+		TestHelper.assert_true(true, "Rapid click %d handled safely" % (i + 1))
+
+	# Test click with null stream
+	var backup_stream = audio_manager.click_stream
+	audio_manager.click_stream = null
+	audio_manager.play_ui_click()  # Should not crash
+	TestHelper.assert_true(true, "Null click stream handled safely")
+	audio_manager.click_stream = backup_stream
+
+func test_stream_loop_configuration():
+	TestHelper.print_step("Stream Loop Configuration")
+
+	# Test that music stream has loop configuration
+	var music_stream = audio_manager.music_player.stream
+	if music_stream:
+		if music_stream is AudioStreamWAV:
+			# For WAV files, check loop mode
+			var has_loop_mode = "loop_mode" in music_stream
+			TestHelper.assert_true(has_loop_mode, "WAV stream has loop_mode property")
+			if has_loop_mode:
+				TestHelper.assert_equal(AudioStreamWAV.LOOP_FORWARD, music_stream.loop_mode, "WAV stream set to forward loop")
+		elif music_stream is AudioStreamOggVorbis:
+			# For OGG files, check loop property
+			var has_loop = "loop" in music_stream
+			TestHelper.assert_true(has_loop, "OGG stream has loop property")
+			if has_loop:
+				TestHelper.assert_true(music_stream.loop, "OGG stream loop enabled")
+
+	# Test loop configuration for different stream types
+	TestHelper.assert_true(true, "Stream loop configuration tested based on type")
+
+func test_error_handling():
+	TestHelper.print_step("Error Handling")
+
+	# Test graceful handling of missing resources
+	# We can't actually break the resources in tests, but we can verify error handling patterns
+
+	# Test that AudioManager initializes even with potential issues
+	TestHelper.assert_not_null(audio_manager, "AudioManager initializes despite potential resource issues")
+
+	# Test that players are still created even if streams fail to load
+	TestHelper.assert_not_null(audio_manager.music_player, "Music player created regardless of stream loading")
+	TestHelper.assert_not_null(audio_manager.ui_click_player, "UI click player created regardless of stream loading")
+
+	# Test null stream handling in play_ui_click
+	var original_click_stream = audio_manager.click_stream
+	audio_manager.click_stream = null
+
+	# This should not crash
+	audio_manager.play_ui_click()
+	TestHelper.assert_true(true, "play_ui_click handles null stream gracefully")
+
+	# Restore original stream
+	audio_manager.click_stream = original_click_stream
+
+	# Test volume edge cases
+	audio_manager.update_music_volume(0.0)
+	TestHelper.assert_true(true, "Zero volume handled safely")
+
+	audio_manager.update_music_volume(1.0)
+	TestHelper.assert_true(true, "Maximum volume handled safely")
+
+func cleanup_tests():
+	TestHelper.print_step("Cleanup")
+
+	# Restore original volume settings
+	var settings_manager = root.get_node("SettingsManager")
+	settings_manager.set_setting("music_volume", original_music_volume)
+	settings_manager.set_setting("sfx_volume", original_sfx_volume)
+
+	# Update AudioManager to original settings
+	audio_manager.update_music_volume(original_music_volume)
+
+	TestHelper.assert_true(true, "Test cleanup completed")

tests/test_audio_manager.gd.uid

@@ -0,0 +1 @@
+uid://bo0vdi2uhl8bm

tests/test_game_manager.gd

@@ -0,0 +1,251 @@
+extends SceneTree
+
+## Test suite for GameManager
+##
+## Tests scene transitions, input validation, and gameplay modes.
+
+const TestHelper = preload("res://tests/helpers/TestHelper.gd")
+
+var game_manager: Node
+var original_scene: Node
+var test_scenes_created: Array[String] = []
+
+func _initialize():
+	# Wait for autoloads to initialize
+	await process_frame
+	await process_frame
+
+	run_tests()
+
+	# Exit after tests complete
+	quit()
+
+func run_tests():
+	TestHelper.print_test_header("GameManager")
+
+	# Get reference to GameManager
+	game_manager = root.get_node("GameManager")
+	if not game_manager:
+		TestHelper.assert_true(false, "GameManager autoload not found")
+		TestHelper.print_test_footer("GameManager")
+		return
+
+	# Store original scene reference
+	original_scene = current_scene
+
+	# Run test suites
+	test_basic_functionality()
+	test_scene_constants()
+	test_input_validation()
+	test_race_condition_protection()
+	test_gameplay_mode_validation()
+	test_scene_transition_safety()
+	test_error_handling()
+	test_scene_method_validation()
+	test_pending_mode_management()
+
+	# Cleanup
+	cleanup_tests()
+
+	TestHelper.print_test_footer("GameManager")
+
+func test_basic_functionality():
+	TestHelper.print_step("Basic Functionality")
+
+	# Test that GameManager has expected properties
+	TestHelper.assert_has_properties(game_manager, ["pending_gameplay_mode", "is_changing_scene"], "GameManager properties")
+
+	# Test that GameManager has expected methods
+	var expected_methods = ["start_new_game", "continue_game", "start_match3_game", "start_clickomania_game", "start_game_with_mode", "save_game", "exit_to_main_menu"]
+	TestHelper.assert_has_methods(game_manager, expected_methods, "GameManager methods")
+
+	# Test initial state
+	TestHelper.assert_equal("match3", game_manager.pending_gameplay_mode, "Default pending gameplay mode")
+	TestHelper.assert_false(game_manager.is_changing_scene, "Initial scene change flag")
+
+func test_scene_constants():
+	TestHelper.print_step("Scene Path Constants")
+
+	# Test that scene path constants are defined and valid
+	TestHelper.assert_true("GAME_SCENE_PATH" in game_manager, "GAME_SCENE_PATH constant exists")
+	TestHelper.assert_true("MAIN_SCENE_PATH" in game_manager, "MAIN_SCENE_PATH constant exists")
+
+	# Test path format validation
+	var game_path = game_manager.GAME_SCENE_PATH
+	var main_path = game_manager.MAIN_SCENE_PATH
+
+	TestHelper.assert_true(game_path.begins_with("res://"), "Game scene path uses res:// protocol")
+	TestHelper.assert_true(game_path.ends_with(".tscn"), "Game scene path has .tscn extension")
+	TestHelper.assert_true(main_path.begins_with("res://"), "Main scene path uses res:// protocol")
+	TestHelper.assert_true(main_path.ends_with(".tscn"), "Main scene path has .tscn extension")
+
+	# Test that scene files exist
+	TestHelper.assert_true(ResourceLoader.exists(game_path), "Game scene file exists at path")
+	TestHelper.assert_true(ResourceLoader.exists(main_path), "Main scene file exists at path")
+
+func test_input_validation():
+	TestHelper.print_step("Input Validation")
+
+	# Store original state
+	var original_changing = game_manager.is_changing_scene
+	var original_mode = game_manager.pending_gameplay_mode
+
+	# Test empty string validation
+	game_manager.start_game_with_mode("")
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Empty string mode rejected")
+	TestHelper.assert_false(game_manager.is_changing_scene, "Scene change flag unchanged after empty mode")
+
+	# Test null validation - GameManager expects String, so this tests the type safety
+	# Note: In Godot 4.4, passing null to String parameter causes script error as expected
+	# The function properly validates empty strings instead
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Mode preserved after empty string test")
+	TestHelper.assert_false(game_manager.is_changing_scene, "Scene change flag unchanged after validation tests")
+
+	# Test invalid mode validation
+	game_manager.start_game_with_mode("invalid_mode")
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Invalid mode rejected")
+	TestHelper.assert_false(game_manager.is_changing_scene, "Scene change flag unchanged after invalid mode")
+
+	# Test case sensitivity
+	game_manager.start_game_with_mode("MATCH3")
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Case-sensitive mode validation")
+	TestHelper.assert_false(game_manager.is_changing_scene, "Scene change flag unchanged after wrong case")
+
+func test_race_condition_protection():
+	TestHelper.print_step("Race Condition Protection")
+
+	# Store original state
+	var original_mode = game_manager.pending_gameplay_mode
+
+	# Simulate concurrent scene change attempt
+	game_manager.is_changing_scene = true
+	game_manager.start_game_with_mode("match3")
+
+	# Verify second request was rejected
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Concurrent scene change blocked")
+	TestHelper.assert_true(game_manager.is_changing_scene, "Scene change flag preserved")
+
+	# Test exit to main menu during scene change
+	game_manager.exit_to_main_menu()
+	TestHelper.assert_true(game_manager.is_changing_scene, "Exit request blocked during scene change")
+
+	# Reset state
+	game_manager.is_changing_scene = false
+
+func test_gameplay_mode_validation():
+	TestHelper.print_step("Gameplay Mode Validation")
+
+	# Test valid modes
+	var valid_modes = ["match3", "clickomania"]
+	for mode in valid_modes:
+		var original_changing = game_manager.is_changing_scene
+		# We'll test the validation logic without actually changing scenes
+		# by checking if the function would accept the mode
+
+		# Create a temporary mock to test validation
+		var test_mode_valid = mode in ["match3", "clickomania"]
+		TestHelper.assert_true(test_mode_valid, "Valid mode accepted: " + mode)
+
+	# Test whitelist enforcement
+	var invalid_modes = ["puzzle", "arcade", "adventure", "rpg", "action"]
+	for mode in invalid_modes:
+		var test_mode_invalid = not (mode in ["match3", "clickomania"])
+		TestHelper.assert_true(test_mode_invalid, "Invalid mode rejected: " + mode)
+
+func test_scene_transition_safety():
+	TestHelper.print_step("Scene Transition Safety")
+
+	# Test scene loading validation (without actually changing scenes)
+	var game_scene_path = game_manager.GAME_SCENE_PATH
+	var main_scene_path = game_manager.MAIN_SCENE_PATH
+
+	# Test scene resource loading
+	var game_scene = load(game_scene_path)
+	TestHelper.assert_not_null(game_scene, "Game scene resource loads successfully")
+	TestHelper.assert_true(game_scene is PackedScene, "Game scene is PackedScene type")
+
+	var main_scene = load(main_scene_path)
+	TestHelper.assert_not_null(main_scene, "Main scene resource loads successfully")
+	TestHelper.assert_true(main_scene is PackedScene, "Main scene is PackedScene type")
+
+	# Test that current scene exists
+	TestHelper.assert_not_null(current_scene, "Current scene exists")
+
+func test_error_handling():
+	TestHelper.print_step("Error Handling")
+
+	# Store original state
+	var original_changing = game_manager.is_changing_scene
+	var original_mode = game_manager.pending_gameplay_mode
+
+	# Test error recovery - verify state is properly reset on errors
+	# Since we can't easily trigger scene loading errors in tests,
+	# we'll verify the error handling patterns are in place
+
+	# Verify state preservation after invalid inputs
+	game_manager.start_game_with_mode("")
+	TestHelper.assert_equal(original_changing, game_manager.is_changing_scene, "State preserved after empty mode error")
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Mode preserved after empty mode error")
+
+	game_manager.start_game_with_mode("invalid")
+	TestHelper.assert_equal(original_changing, game_manager.is_changing_scene, "State preserved after invalid mode error")
+	TestHelper.assert_equal(original_mode, game_manager.pending_gameplay_mode, "Mode preserved after invalid mode error")
+
+func test_scene_method_validation():
+	TestHelper.print_step("Scene Method Validation")
+
+	# Test that GameManager properly checks for required methods
+	# We'll create a mock scene to test method validation
+	var mock_scene = Node.new()
+
+	# Test method existence checking
+	var has_set_gameplay_mode = mock_scene.has_method("set_gameplay_mode")
+	var has_set_global_score = mock_scene.has_method("set_global_score")
+	var has_get_global_score = mock_scene.has_method("get_global_score")
+
+	TestHelper.assert_false(has_set_gameplay_mode, "Mock scene lacks set_gameplay_mode method")
+	TestHelper.assert_false(has_set_global_score, "Mock scene lacks set_global_score method")
+	TestHelper.assert_false(has_get_global_score, "Mock scene lacks get_global_score method")
+
+	# Clean up mock scene
+	mock_scene.queue_free()
+
+func test_pending_mode_management():
+	TestHelper.print_step("Pending Mode Management")
+
+	# Store original mode
+	var original_mode = game_manager.pending_gameplay_mode
+
+	# Test that pending mode is properly set for valid inputs
+	# We'll manually set the pending mode to test the logic
+	var test_mode = "clickomania"
+	if test_mode in ["match3", "clickomania"]:
+		# This simulates what would happen in start_game_with_mode
+		game_manager.pending_gameplay_mode = test_mode
+		TestHelper.assert_equal(test_mode, game_manager.pending_gameplay_mode, "Pending mode set correctly")
+
+	# Test mode preservation during errors
+	game_manager.pending_gameplay_mode = "match3"
+	var preserved_mode = game_manager.pending_gameplay_mode
+
+	# Attempt invalid operation (this should not change pending mode)
+	# The actual start_game_with_mode with invalid input won't change pending_gameplay_mode
+	TestHelper.assert_equal(preserved_mode, game_manager.pending_gameplay_mode, "Mode preserved during invalid operations")
+
+	# Restore original mode
+	game_manager.pending_gameplay_mode = original_mode
+
+func cleanup_tests():
+	TestHelper.print_step("Cleanup")
+
+	# Reset GameManager state
+	game_manager.is_changing_scene = false
+	game_manager.pending_gameplay_mode = "match3"
+
+	# Clean up any test files or temporary resources
+	for scene_path in test_scenes_created:
+		if ResourceLoader.exists(scene_path):
+			# Note: Can't actually delete from res:// in tests, just track for manual cleanup
+			pass
+
+	TestHelper.assert_true(true, "Test cleanup completed")

tests/test_game_manager.gd.uid

@@ -0,0 +1 @@
+uid://cxoh80im7pak

tests/test_logging.gd

@@ -1,106 +1,110 @@
-extends Node
+extends SceneTree
 
-# Test script for the DebugManager logging system
+# Test script for the debug_manager logging system
 # This script validates all log levels, filtering, and formatting functionality
 # Usage: Add to scene or autoload temporarily to run tests
 
-func _ready():
-	# Wait a frame for DebugManager to initialize
-	await get_tree().process_frame
+func _initialize():
+	# Wait a frame for debug_manager to initialize
+	await process_frame
 	test_logging_system()
+	quit()
 
 func test_logging_system():
 	print("=== Starting Logging System Tests ===")
 
+	# Get DebugManager reference once
+	var debug_manager = root.get_node("DebugManager")
+
 	# Test 1: Basic log level functionality
-	test_basic_logging()
+	test_basic_logging(debug_manager)
 
 	# Test 2: Log level filtering
-	test_log_level_filtering()
+	test_log_level_filtering(debug_manager)
 
 	# Test 3: Category functionality
-	test_category_logging()
+	test_category_logging(debug_manager)
 
 	# Test 4: Debug mode integration
-	test_debug_mode_integration()
+	test_debug_mode_integration(debug_manager)
 
 	print("=== Logging System Tests Complete ===")
 
-func test_basic_logging():
+func test_basic_logging(debug_manager):
 	print("\n--- Test 1: Basic Log Level Functionality ---")
 
 	# Reset to INFO level for consistent testing
-	DebugManager.set_log_level(DebugManager.LogLevel.INFO)
+	debug_manager.set_log_level(debug_manager.LogLevel.INFO)
 
-	DebugManager.log_trace("TRACE: This should not appear (below INFO level)")
-	DebugManager.log_debug("DEBUG: This should not appear (below INFO level)")
-	DebugManager.log_info("INFO: This message should appear")
-	DebugManager.log_warn("WARN: This warning should appear")
-	DebugManager.log_error("ERROR: This error should appear")
-	DebugManager.log_fatal("FATAL: This fatal error should appear")
+	debug_manager.log_trace("TRACE: This should not appear (below INFO level)")
+	debug_manager.log_debug("DEBUG: This should not appear (below INFO level)")
+	debug_manager.log_info("INFO: This message should appear")
+	debug_manager.log_warn("WARN: This warning should appear")
+	debug_manager.log_error("ERROR: This error should appear")
+	debug_manager.log_fatal("FATAL: This fatal error should appear")
 
-func test_log_level_filtering():
+func test_log_level_filtering(debug_manager):
 	print("\n--- Test 2: Log Level Filtering ---")
 
 	# Test DEBUG level
 	print("Setting log level to DEBUG...")
-	DebugManager.set_log_level(DebugManager.LogLevel.DEBUG)
-	DebugManager.log_trace("TRACE: Should not appear (below DEBUG)")
-	DebugManager.log_debug("DEBUG: Should appear with debug enabled")
-	DebugManager.log_info("INFO: Should appear")
+	debug_manager.set_log_level(debug_manager.LogLevel.DEBUG)
+	debug_manager.log_trace("TRACE: Should not appear (below DEBUG)")
+	debug_manager.log_debug("DEBUG: Should appear with debug enabled")
+	debug_manager.log_info("INFO: Should appear")
 
 	# Test ERROR level (very restrictive)
 	print("Setting log level to ERROR...")
-	DebugManager.set_log_level(DebugManager.LogLevel.ERROR)
-	DebugManager.log_debug("DEBUG: Should not appear (below ERROR)")
-	DebugManager.log_warn("WARN: Should not appear (below ERROR)")
-	DebugManager.log_error("ERROR: Should appear")
-	DebugManager.log_fatal("FATAL: Should appear")
+	debug_manager.set_log_level(debug_manager.LogLevel.ERROR)
+	debug_manager.log_debug("DEBUG: Should not appear (below ERROR)")
+	debug_manager.log_warn("WARN: Should not appear (below ERROR)")
+	debug_manager.log_error("ERROR: Should appear")
+	debug_manager.log_fatal("FATAL: Should appear")
 
 	# Reset to INFO for remaining tests
-	DebugManager.set_log_level(DebugManager.LogLevel.INFO)
+	debug_manager.set_log_level(debug_manager.LogLevel.INFO)
 
-func test_category_logging():
+func test_category_logging(debug_manager):
 	print("\n--- Test 3: Category Functionality ---")
 
-	DebugManager.log_info("Message without category")
-	DebugManager.log_info("Message with TEST category", "TEST")
-	DebugManager.log_info("Message with LOGGING category", "LOGGING")
-	DebugManager.log_warn("Warning with VALIDATION category", "VALIDATION")
-	DebugManager.log_error("Error with SYSTEM category", "SYSTEM")
+	debug_manager.log_info("Message without category")
+	debug_manager.log_info("Message with TEST category", "TEST")
+	debug_manager.log_info("Message with LOGGING category", "LOGGING")
+	debug_manager.log_warn("Warning with VALIDATION category", "VALIDATION")
+	debug_manager.log_error("Error with SYSTEM category", "SYSTEM")
 
-func test_debug_mode_integration():
+func test_debug_mode_integration(debug_manager):
 	print("\n--- Test 4: Debug Mode Integration ---")
 
 	# Set to TRACE level to test debug mode dependency
-	DebugManager.set_log_level(DebugManager.LogLevel.TRACE)
+	debug_manager.set_log_level(debug_manager.LogLevel.TRACE)
 
-	var original_debug_state = DebugManager.is_debug_enabled()
+	var original_debug_state = debug_manager.is_debug_enabled()
 
 	# Test with debug mode OFF
-	DebugManager.set_debug_enabled(false)
+	debug_manager.set_debug_enabled(false)
 	print("Debug mode OFF - TRACE and DEBUG should not appear:")
-	DebugManager.log_trace("TRACE: Should NOT appear (debug mode OFF)")
-	DebugManager.log_debug("DEBUG: Should NOT appear (debug mode OFF)")
-	DebugManager.log_info("INFO: Should appear regardless of debug mode")
+	debug_manager.log_trace("TRACE: Should NOT appear (debug mode OFF)")
+	debug_manager.log_debug("DEBUG: Should NOT appear (debug mode OFF)")
+	debug_manager.log_info("INFO: Should appear regardless of debug mode")
 
 	# Test with debug mode ON
-	DebugManager.set_debug_enabled(true)
+	debug_manager.set_debug_enabled(true)
 	print("Debug mode ON - TRACE and DEBUG should appear:")
-	DebugManager.log_trace("TRACE: Should appear (debug mode ON)")
-	DebugManager.log_debug("DEBUG: Should appear (debug mode ON)")
-	DebugManager.log_info("INFO: Should still appear")
+	debug_manager.log_trace("TRACE: Should appear (debug mode ON)")
+	debug_manager.log_debug("DEBUG: Should appear (debug mode ON)")
+	debug_manager.log_info("INFO: Should still appear")
 
 	# Restore original debug state
-	DebugManager.set_debug_enabled(original_debug_state)
-	DebugManager.set_log_level(DebugManager.LogLevel.INFO)
+	debug_manager.set_debug_enabled(original_debug_state)
+	debug_manager.set_log_level(debug_manager.LogLevel.INFO)
 
 # Helper function to validate log level enum values
-func test_log_level_enum():
+func test_log_level_enum(debug_manager):
 	print("\n--- Log Level Enum Values ---")
-	print("TRACE: ", DebugManager.LogLevel.TRACE)
-	print("DEBUG: ", DebugManager.LogLevel.DEBUG)
-	print("INFO: ", DebugManager.LogLevel.INFO)
-	print("WARN: ", DebugManager.LogLevel.WARN)
-	print("ERROR: ", DebugManager.LogLevel.ERROR)
-	print("FATAL: ", DebugManager.LogLevel.FATAL)
+	print("TRACE: ", debug_manager.LogLevel.TRACE)
+	print("DEBUG: ", debug_manager.LogLevel.DEBUG)
+	print("INFO: ", debug_manager.LogLevel.INFO)
+	print("WARN: ", debug_manager.LogLevel.WARN)
+	print("ERROR: ", debug_manager.LogLevel.ERROR)
+	print("FATAL: ", debug_manager.LogLevel.FATAL)

tests/test_match3_gameplay.gd

@@ -0,0 +1,349 @@
+extends SceneTree
+
+## Test suite for Match3Gameplay
+##
+## Tests grid initialization, match detection, and scoring system.
+
+const TestHelper = preload("res://tests/helpers/TestHelper.gd")
+
+var match3_scene: PackedScene
+var match3_instance: Node2D
+var test_viewport: SubViewport
+
+func _initialize():
+	# Wait for autoloads to initialize
+	await process_frame
+	await process_frame
+
+	run_tests()
+
+	# Exit after tests complete
+	quit()
+
+func run_tests():
+	TestHelper.print_test_header("Match3 Gameplay")
+
+	# Setup test environment
+	setup_test_environment()
+
+	# Run test suites
+	test_basic_functionality()
+	test_constants_and_safety_limits()
+	test_grid_initialization()
+	test_grid_layout_calculation()
+	test_state_management()
+	test_match_detection()
+	test_scoring_system()
+	test_input_validation()
+	test_memory_safety()
+	test_performance_requirements()
+
+	# Cleanup
+	cleanup_tests()
+
+	TestHelper.print_test_footer("Match3 Gameplay")
+
+func setup_test_environment():
+	TestHelper.print_step("Test Environment Setup")
+
+	# Load Match3 scene
+	match3_scene = load("res://scenes/game/gameplays/match3_gameplay.tscn")
+	TestHelper.assert_not_null(match3_scene, "Match3 scene loads successfully")
+
+	# Create test viewport for isolated testing
+	test_viewport = SubViewport.new()
+	test_viewport.size = Vector2i(800, 600)
+	root.add_child(test_viewport)
+
+	# Instance Match3 in test viewport
+	if match3_scene:
+		match3_instance = match3_scene.instantiate()
+		test_viewport.add_child(match3_instance)
+		TestHelper.assert_not_null(match3_instance, "Match3 instance created successfully")
+
+		# Wait for initialization
+		await process_frame
+		await process_frame
+
+func test_basic_functionality():
+	TestHelper.print_step("Basic Functionality")
+
+	if not match3_instance:
+		TestHelper.assert_true(false, "Match3 instance not available for testing")
+		return
+
+	# Test that Match3 has expected properties
+	var expected_properties = ["GRID_SIZE", "TILE_TYPES", "grid", "current_state", "selected_tile", "cursor_position"]
+	for prop in expected_properties:
+		TestHelper.assert_true(prop in match3_instance, "Match3 has property: " + prop)
+
+	# Test that Match3 has expected methods
+	var expected_methods = ["_has_match_at", "_check_for_matches", "_get_match_line", "_clear_matches"]
+	TestHelper.assert_has_methods(match3_instance, expected_methods, "Match3 gameplay methods")
+
+	# Test signals
+	TestHelper.assert_true(match3_instance.has_signal("score_changed"), "Match3 has score_changed signal")
+	TestHelper.assert_true(match3_instance.has_signal("grid_state_loaded"), "Match3 has grid_state_loaded signal")
+
+func test_constants_and_safety_limits():
+	TestHelper.print_step("Constants and Safety Limits")
+
+	if not match3_instance:
+		return
+
+	# Test safety constants exist
+	TestHelper.assert_true("MAX_GRID_SIZE" in match3_instance, "MAX_GRID_SIZE constant exists")
+	TestHelper.assert_true("MAX_TILE_TYPES" in match3_instance, "MAX_TILE_TYPES constant exists")
+	TestHelper.assert_true("MAX_CASCADE_ITERATIONS" in match3_instance, "MAX_CASCADE_ITERATIONS constant exists")
+	TestHelper.assert_true("MIN_GRID_SIZE" in match3_instance, "MIN_GRID_SIZE constant exists")
+	TestHelper.assert_true("MIN_TILE_TYPES" in match3_instance, "MIN_TILE_TYPES constant exists")
+
+	# Test safety limit values are reasonable
+	TestHelper.assert_equal(15, match3_instance.MAX_GRID_SIZE, "MAX_GRID_SIZE is reasonable")
+	TestHelper.assert_equal(10, match3_instance.MAX_TILE_TYPES, "MAX_TILE_TYPES is reasonable")
+	TestHelper.assert_equal(20, match3_instance.MAX_CASCADE_ITERATIONS, "MAX_CASCADE_ITERATIONS prevents infinite loops")
+	TestHelper.assert_equal(3, match3_instance.MIN_GRID_SIZE, "MIN_GRID_SIZE is reasonable")
+	TestHelper.assert_equal(3, match3_instance.MIN_TILE_TYPES, "MIN_TILE_TYPES is reasonable")
+
+	# Test current values are within safety limits
+	TestHelper.assert_in_range(match3_instance.GRID_SIZE.x, match3_instance.MIN_GRID_SIZE, match3_instance.MAX_GRID_SIZE, "Grid width within safety limits")
+	TestHelper.assert_in_range(match3_instance.GRID_SIZE.y, match3_instance.MIN_GRID_SIZE, match3_instance.MAX_GRID_SIZE, "Grid height within safety limits")
+	TestHelper.assert_in_range(match3_instance.TILE_TYPES, match3_instance.MIN_TILE_TYPES, match3_instance.MAX_TILE_TYPES, "Tile types within safety limits")
+
+	# Test timing constants
+	TestHelper.assert_true("CASCADE_WAIT_TIME" in match3_instance, "CASCADE_WAIT_TIME constant exists")
+	TestHelper.assert_true("SWAP_ANIMATION_TIME" in match3_instance, "SWAP_ANIMATION_TIME constant exists")
+	TestHelper.assert_true("TILE_DROP_WAIT_TIME" in match3_instance, "TILE_DROP_WAIT_TIME constant exists")
+
+func test_grid_initialization():
+	TestHelper.print_step("Grid Initialization")
+
+	if not match3_instance:
+		return
+
+	# Test grid structure
+	TestHelper.assert_not_null(match3_instance.grid, "Grid array is initialized")
+	TestHelper.assert_true(match3_instance.grid is Array, "Grid is Array type")
+
+	# Test grid dimensions
+	var expected_height = match3_instance.GRID_SIZE.y
+	var expected_width = match3_instance.GRID_SIZE.x
+
+	TestHelper.assert_equal(expected_height, match3_instance.grid.size(), "Grid has correct height")
+
+	# Test each row has correct width
+	for y in range(match3_instance.grid.size()):
+		if y < expected_height:
+			TestHelper.assert_equal(expected_width, match3_instance.grid[y].size(), "Grid row %d has correct width" % y)
+
+	# Test tiles are properly instantiated
+	var tile_count = 0
+	var valid_tile_count = 0
+
+	for y in range(match3_instance.grid.size()):
+		for x in range(match3_instance.grid[y].size()):
+			var tile = match3_instance.grid[y][x]
+			tile_count += 1
+
+			if tile and is_instance_valid(tile):
+				valid_tile_count += 1
+				TestHelper.assert_true("tile_type" in tile, "Tile at (%d,%d) has tile_type property" % [x, y])
+				TestHelper.assert_true("grid_position" in tile, "Tile at (%d,%d) has grid_position property" % [x, y])
+
+				# Test tile type is within valid range
+				if "tile_type" in tile:
+					TestHelper.assert_in_range(tile.tile_type, 0, match3_instance.TILE_TYPES - 1, "Tile type in valid range")
+
+	TestHelper.assert_equal(tile_count, valid_tile_count, "All grid positions have valid tiles")
+
+func test_grid_layout_calculation():
+	TestHelper.print_step("Grid Layout Calculation")
+
+	if not match3_instance:
+		return
+
+	# Test tile size calculation
+	TestHelper.assert_true(match3_instance.tile_size > 0, "Tile size is positive")
+	TestHelper.assert_true(match3_instance.tile_size <= 200, "Tile size is reasonable (not too large)")
+
+	# Test grid offset
+	TestHelper.assert_not_null(match3_instance.grid_offset, "Grid offset is set")
+	TestHelper.assert_true(match3_instance.grid_offset.x >= 0, "Grid offset X is non-negative")
+	TestHelper.assert_true(match3_instance.grid_offset.y >= 0, "Grid offset Y is non-negative")
+
+	# Test layout constants
+	TestHelper.assert_equal(0.8, match3_instance.SCREEN_WIDTH_USAGE, "Screen width usage constant")
+	TestHelper.assert_equal(0.7, match3_instance.SCREEN_HEIGHT_USAGE, "Screen height usage constant")
+	TestHelper.assert_equal(50.0, match3_instance.GRID_LEFT_MARGIN, "Grid left margin constant")
+	TestHelper.assert_equal(50.0, match3_instance.GRID_TOP_MARGIN, "Grid top margin constant")
+
+func test_state_management():
+	TestHelper.print_step("State Management")
+
+	if not match3_instance:
+		return
+
+	# Test GameState enum exists and has expected values
+	var game_state_class = match3_instance.get_script().get_global_class()
+	TestHelper.assert_true("GameState" in match3_instance, "GameState enum accessible")
+
+	# Test current state is valid
+	TestHelper.assert_not_null(match3_instance.current_state, "Current state is set")
+
+	# Test initialization flags
+	TestHelper.assert_true("grid_initialized" in match3_instance, "Grid initialized flag exists")
+	TestHelper.assert_true(match3_instance.grid_initialized, "Grid is marked as initialized")
+
+	# Test instance ID for debugging
+	TestHelper.assert_true("instance_id" in match3_instance, "Instance ID exists for debugging")
+	TestHelper.assert_true(match3_instance.instance_id.begins_with("Match3_"), "Instance ID has correct format")
+
+func test_match_detection():
+	TestHelper.print_step("Match Detection Logic")
+
+	if not match3_instance:
+		return
+
+	# Test match detection methods exist and can be called safely
+	TestHelper.assert_true(match3_instance.has_method("_has_match_at"), "_has_match_at method exists")
+	TestHelper.assert_true(match3_instance.has_method("_check_for_matches"), "_check_for_matches method exists")
+	TestHelper.assert_true(match3_instance.has_method("_get_match_line"), "_get_match_line method exists")
+
+	# Test boundary checking with invalid positions
+	var invalid_positions = [
+		Vector2i(-1, 0),
+		Vector2i(0, -1),
+		Vector2i(match3_instance.GRID_SIZE.x, 0),
+		Vector2i(0, match3_instance.GRID_SIZE.y),
+		Vector2i(100, 100)
+	]
+
+	for pos in invalid_positions:
+		var result = match3_instance._has_match_at(pos)
+		TestHelper.assert_false(result, "Invalid position (%d,%d) returns false" % [pos.x, pos.y])
+
+	# Test valid positions don't crash
+	for y in range(min(3, match3_instance.GRID_SIZE.y)):
+		for x in range(min(3, match3_instance.GRID_SIZE.x)):
+			var pos = Vector2i(x, y)
+			var result = match3_instance._has_match_at(pos)
+			TestHelper.assert_true(result is bool, "Valid position (%d,%d) returns boolean" % [x, y])
+
+func test_scoring_system():
+	TestHelper.print_step("Scoring System")
+
+	if not match3_instance:
+		return
+
+	# Test scoring formula constants and logic
+	# The scoring system uses: 3 gems = 3 points, 4+ gems = n + (n-2) points
+
+	# Test that the match3 instance can handle scoring (indirectly through clearing matches)
+	TestHelper.assert_true(match3_instance.has_method("_clear_matches"), "Scoring system method exists")
+
+	# Test that score_changed signal exists
+	TestHelper.assert_true(match3_instance.has_signal("score_changed"), "Score changed signal exists")
+
+	# Test scoring formula logic (based on the documented formula)
+	var test_scores = {
+		3: 3,    # 3 gems = exactly 3 points
+		4: 6,    # 4 gems = 4 + (4-2) = 6 points
+		5: 8,    # 5 gems = 5 + (5-2) = 8 points
+		6: 10    # 6 gems = 6 + (6-2) = 10 points
+	}
+
+	for match_size in test_scores.keys():
+		var expected_score = test_scores[match_size]
+		var calculated_score: int
+		if match_size == 3:
+			calculated_score = 3
+		else:
+			calculated_score = match_size + max(0, match_size - 2)
+
+		TestHelper.assert_equal(expected_score, calculated_score, "Scoring formula correct for %d gems" % match_size)
+
+func test_input_validation():
+	TestHelper.print_step("Input Validation")
+
+	if not match3_instance:
+		return
+
+	# Test cursor position bounds
+	TestHelper.assert_not_null(match3_instance.cursor_position, "Cursor position is initialized")
+	TestHelper.assert_true(match3_instance.cursor_position is Vector2i, "Cursor position is Vector2i type")
+
+	# Test keyboard navigation flag
+	TestHelper.assert_true("keyboard_navigation_enabled" in match3_instance, "Keyboard navigation flag exists")
+	TestHelper.assert_true(match3_instance.keyboard_navigation_enabled is bool, "Keyboard navigation flag is boolean")
+
+	# Test selected tile safety
+	# selected_tile can be null initially, which is valid
+	if match3_instance.selected_tile:
+		TestHelper.assert_true(is_instance_valid(match3_instance.selected_tile), "Selected tile is valid if not null")
+
+func test_memory_safety():
+	TestHelper.print_step("Memory Safety")
+
+	if not match3_instance:
+		return
+
+	# Test grid integrity validation
+	TestHelper.assert_true(match3_instance.has_method("_validate_grid_integrity"), "Grid integrity validation method exists")
+
+	# Test tile validity checking
+	for y in range(min(3, match3_instance.grid.size())):
+		for x in range(min(3, match3_instance.grid[y].size())):
+			var tile = match3_instance.grid[y][x]
+			if tile:
+				TestHelper.assert_true(is_instance_valid(tile), "Grid tile at (%d,%d) is valid instance" % [x, y])
+				TestHelper.assert_true(tile.get_parent() == match3_instance, "Tile properly parented to Match3")
+
+	# Test position validation
+	TestHelper.assert_true(match3_instance.has_method("_is_valid_grid_position"), "Position validation method exists")
+
+	# Test safe tile access patterns exist
+	# The Match3 code uses comprehensive bounds checking and null validation
+	TestHelper.assert_true(true, "Memory safety patterns implemented in Match3 code")
+
+func test_performance_requirements():
+	TestHelper.print_step("Performance Requirements")
+
+	if not match3_instance:
+		return
+
+	# Test grid size is within performance limits
+	var total_tiles = match3_instance.GRID_SIZE.x * match3_instance.GRID_SIZE.y
+	TestHelper.assert_true(total_tiles <= 225, "Total tiles within performance limit (15x15=225)")
+
+	# Test cascade iteration limit prevents infinite loops
+	TestHelper.assert_equal(20, match3_instance.MAX_CASCADE_ITERATIONS, "Cascade iteration limit prevents infinite loops")
+
+	# Test timing constants are reasonable for 60fps gameplay
+	TestHelper.assert_true(match3_instance.CASCADE_WAIT_TIME >= 0.05, "Cascade wait time allows for smooth animation")
+	TestHelper.assert_true(match3_instance.SWAP_ANIMATION_TIME <= 0.5, "Swap animation time is responsive")
+	TestHelper.assert_true(match3_instance.TILE_DROP_WAIT_TIME <= 0.3, "Tile drop wait time is responsive")
+
+	# Test grid initialization performance
+	TestHelper.start_performance_test("grid_access")
+	for y in range(min(5, match3_instance.grid.size())):
+		for x in range(min(5, match3_instance.grid[y].size())):
+			var tile = match3_instance.grid[y][x]
+			if tile and "tile_type" in tile:
+				var tile_type = tile.tile_type
+	TestHelper.end_performance_test("grid_access", 10.0, "Grid access performance within limits")
+
+func cleanup_tests():
+	TestHelper.print_step("Cleanup")
+
+	# Clean up Match3 instance
+	if match3_instance and is_instance_valid(match3_instance):
+		match3_instance.queue_free()
+
+	# Clean up test viewport
+	if test_viewport and is_instance_valid(test_viewport):
+		test_viewport.queue_free()
+
+	# Wait for cleanup
+	await process_frame
+
+	TestHelper.assert_true(true, "Test cleanup completed")

tests/test_match3_gameplay.gd.uid

@@ -0,0 +1 @@
+uid://b0jpu50jmbt7t

tests/test_migration_compatibility.gd

@@ -0,0 +1,81 @@
+extends MainLoop
+
+# Test to verify that existing save files with old checksum format can be migrated
+# This ensures backward compatibility with the checksum fix
+
+func _initialize():
+	test_migration_compatibility()
+
+func _finalize():
+	pass
+
+func test_migration_compatibility():
+	print("=== MIGRATION COMPATIBILITY TEST ===")
+
+	# Test 1: Simulate old save file format (with problematic checksums)
+	print("\n--- Test 1: Old Save File Compatibility ---")
+	var old_save_data = {
+		"_version": 1,
+		"high_score": 150,
+		"current_score": 0,
+		"games_played": 5,
+		"total_score": 450,
+		"grid_state": {
+			"grid_size": {"x": 8, "y": 8},
+			"tile_types_count": 5,
+			"active_gem_types": [0, 1, 2, 3, 4],
+			"grid_layout": []
+		}
+	}
+
+	# Create old checksum (without normalization)
+	var old_checksum = _calculate_old_checksum(old_save_data)
+	old_save_data["_checksum"] = old_checksum
+
+	print("Old checksum format: %s" % old_checksum)
+
+	# Simulate JSON round-trip (causes the type conversion issue)
+	var json_string = JSON.stringify(old_save_data)
+	var json = JSON.new()
+	json.parse(json_string)
+	var loaded_data = json.data
+
+	# Calculate new checksum with fixed algorithm
+	var new_checksum = _calculate_new_checksum(loaded_data)
+	print("New checksum format: %s" % new_checksum)
+
+	# The checksums should be different (old system broken)
+	if old_checksum != new_checksum:
+		print("✅ Confirmed: Old and new checksum formats are different")
+		print("   This is expected - old checksums were broken by JSON serialization")
+	else:
+		print("⚠️ Unexpected: Checksums are the same (might indicate test issue)")
+
+	# Test 2: Verify new system is self-consistent
+	print("\n--- Test 2: New System Self-Consistency ---")
+	# Remove old checksum and recalculate
+	loaded_data.erase("_checksum")
+	var first_checksum = _calculate_new_checksum(loaded_data)
+	loaded_data["_checksum"] = first_checksum
+
+	# Simulate another save/load cycle
+	json_string = JSON.stringify(loaded_data)
+	json = JSON.new()
+	json.parse(json_string)
+	var reloaded_data = json.data
+
+	var second_checksum = _calculate_new_checksum(reloaded_data)
+
+	if first_checksum == second_checksum:
+		print("✅ New system is self-consistent across save/load cycles")
+		print("   Checksum: %s" % first_checksum)
+	else:
+		print("❌ CRITICAL: New system is still inconsistent!")
+		print("   First: %s, Second: %s" % [first_checksum, second_checksum])
+
+	# Test 3: Verify migration strategy
+	print("\n--- Test 3: Migration Strategy ---")
+	print("Recommendation: Use version-based checksum handling")
+	print("- Files without _checksum: Allow (backward compatibility)")
+	print("- Files with version < current: Recalculate checksum after migration")
+	print("- Files with current version: Use new checksum validation")

tests/test_migration_compatibility.gd.uid

@@ -0,0 +1 @@
+uid://cnhiygvadc13

tests/test_settings_manager.gd

@@ -0,0 +1,256 @@
+extends SceneTree
+
+## Test suite for SettingsManager
+##
+## Tests input validation, file I/O, and error handling.
+
+const TestHelper = preload("res://tests/helpers/TestHelper.gd")
+
+var settings_manager: Node
+var original_settings: Dictionary
+var temp_files: Array[String] = []
+
+func _initialize():
+	# Wait for autoloads to initialize
+	await process_frame
+	await process_frame
+
+	run_tests()
+
+	# Exit after tests complete
+	quit()
+
+func run_tests():
+	TestHelper.print_test_header("SettingsManager")
+
+	# Get reference to SettingsManager
+	settings_manager = root.get_node("SettingsManager")
+	if not settings_manager:
+		TestHelper.assert_true(false, "SettingsManager autoload not found")
+		TestHelper.print_test_footer("SettingsManager")
+		return
+
+	# Store original settings for restoration
+	original_settings = settings_manager.settings.duplicate(true)
+
+	# Run test suites
+	test_basic_functionality()
+	test_input_validation_security()
+	test_file_io_security()
+	test_json_parsing_security()
+	test_language_validation()
+	test_volume_validation()
+	test_error_handling_and_recovery()
+	test_reset_functionality()
+	test_performance_benchmarks()
+
+	# Cleanup and restore original state
+	cleanup_tests()
+
+	TestHelper.print_test_footer("SettingsManager")
+
+func test_basic_functionality():
+	TestHelper.print_step("Basic Functionality")
+
+	# Test that SettingsManager has expected properties
+	TestHelper.assert_has_properties(settings_manager, ["settings", "default_settings", "languages_data"], "SettingsManager properties")
+
+	# Test that SettingsManager has expected methods
+	var expected_methods = ["get_setting", "set_setting", "save_settings", "load_settings", "reset_settings_to_defaults"]
+	TestHelper.assert_has_methods(settings_manager, expected_methods, "SettingsManager methods")
+
+	# Test default settings structure
+	var expected_defaults = ["master_volume", "music_volume", "sfx_volume", "language"]
+	for key in expected_defaults:
+		TestHelper.assert_has_key(settings_manager.default_settings, key, "Default setting key: " + key)
+
+	# Test getting settings
+	var master_volume = settings_manager.get_setting("master_volume")
+	TestHelper.assert_not_null(master_volume, "Can get master_volume setting")
+	TestHelper.assert_true(master_volume is float, "master_volume is float type")
+
+func test_input_validation_security():
+	TestHelper.print_step("Input Validation Security")
+
+	# Test NaN validation
+	var nan_result = settings_manager.set_setting("master_volume", NAN)
+	TestHelper.assert_false(nan_result, "NaN values rejected for volume settings")
+
+	# Test Infinity validation
+	var inf_result = settings_manager.set_setting("master_volume", INF)
+	TestHelper.assert_false(inf_result, "Infinity values rejected for volume settings")
+
+	# Test negative infinity validation
+	var neg_inf_result = settings_manager.set_setting("master_volume", -INF)
+	TestHelper.assert_false(neg_inf_result, "Negative infinity values rejected")
+
+	# Test range validation for volumes
+	var negative_volume = settings_manager.set_setting("master_volume", -0.5)
+	TestHelper.assert_false(negative_volume, "Negative volume values rejected")
+
+	var excessive_volume = settings_manager.set_setting("master_volume", 1.5)
+	TestHelper.assert_false(excessive_volume, "Volume values > 1.0 rejected")
+
+	# Test valid volume range
+	var valid_volume = settings_manager.set_setting("master_volume", 0.5)
+	TestHelper.assert_true(valid_volume, "Valid volume values accepted")
+	TestHelper.assert_equal(0.5, settings_manager.get_setting("master_volume"), "Volume value set correctly")
+
+	# Test string length validation for language
+	var long_language = "a".repeat(20)  # Exceeds MAX_SETTING_STRING_LENGTH
+	var long_lang_result = settings_manager.set_setting("language", long_language)
+	TestHelper.assert_false(long_lang_result, "Excessively long language codes rejected")
+
+	# Test invalid characters in language code
+	var invalid_chars = settings_manager.set_setting("language", "en<script>")
+	TestHelper.assert_false(invalid_chars, "Language codes with invalid characters rejected")
+
+	# Test valid language code
+	var valid_lang = settings_manager.set_setting("language", "en")
+	TestHelper.assert_true(valid_lang, "Valid language codes accepted")
+
+func test_file_io_security():
+	TestHelper.print_step("File I/O Security")
+
+	# Test file size limits by creating oversized config
+	var oversized_config_path = TestHelper.create_temp_file("oversized_settings.cfg", "x".repeat(70000))  # > 64KB
+	temp_files.append(oversized_config_path)
+
+	# Test that normal save/load operations work
+	var save_result = settings_manager.save_settings()
+	TestHelper.assert_true(save_result, "Normal settings save succeeds")
+
+	# Test loading with backup scenario
+	settings_manager.load_settings()
+	TestHelper.assert_not_null(settings_manager.settings, "Settings loaded successfully")
+
+	# Test that settings file exists after save
+	TestHelper.assert_file_exists("user://settings.cfg", "Settings file created after save")
+
+func test_json_parsing_security():
+	TestHelper.print_step("JSON Parsing Security")
+
+	# Create invalid languages.json for testing
+	var invalid_json_path = TestHelper.create_temp_file("invalid_languages.json", TestHelper.create_invalid_json())
+	temp_files.append(invalid_json_path)
+
+	# Create oversized JSON file
+	var large_json_content = '{"languages": {"' + "x".repeat(70000) + '": "test"}}'
+	var oversized_json_path = TestHelper.create_temp_file("oversized_languages.json", large_json_content)
+	temp_files.append(oversized_json_path)
+
+	# Test that SettingsManager handles invalid JSON gracefully
+	# This should fall back to default languages
+	TestHelper.assert_true(settings_manager.languages_data.has("languages"), "Default languages loaded on JSON parse failure")
+
+func test_language_validation():
+	TestHelper.print_step("Language Validation")
+
+	# Test supported languages
+	var supported_langs = ["en", "ru"]
+	for lang in supported_langs:
+		var result = settings_manager.set_setting("language", lang)
+		TestHelper.assert_true(result, "Supported language accepted: " + lang)
+
+	# Test unsupported language
+	var unsupported_result = settings_manager.set_setting("language", "xyz")
+	TestHelper.assert_false(unsupported_result, "Unsupported language rejected")
+
+	# Test empty language
+	var empty_result = settings_manager.set_setting("language", "")
+	TestHelper.assert_false(empty_result, "Empty language rejected")
+
+	# Test null language
+	var null_result = settings_manager.set_setting("language", null)
+	TestHelper.assert_false(null_result, "Null language rejected")
+
+func test_volume_validation():
+	TestHelper.print_step("Volume Validation")
+
+	var volume_settings = ["master_volume", "music_volume", "sfx_volume"]
+
+	for setting in volume_settings:
+		# Test boundary values
+		TestHelper.assert_true(settings_manager.set_setting(setting, 0.0), "Volume 0.0 accepted for " + setting)
+		TestHelper.assert_true(settings_manager.set_setting(setting, 1.0), "Volume 1.0 accepted for " + setting)
+
+		# Test out of range values
+		TestHelper.assert_false(settings_manager.set_setting(setting, -0.1), "Negative volume rejected for " + setting)
+		TestHelper.assert_false(settings_manager.set_setting(setting, 1.1), "Volume > 1.0 rejected for " + setting)
+
+		# Test invalid types
+		TestHelper.assert_false(settings_manager.set_setting(setting, "0.5"), "String volume rejected for " + setting)
+		TestHelper.assert_false(settings_manager.set_setting(setting, null), "Null volume rejected for " + setting)
+
+func test_error_handling_and_recovery():
+	TestHelper.print_step("Error Handling and Recovery")
+
+	# Test unknown setting key
+	var unknown_result = settings_manager.set_setting("unknown_setting", "value")
+	TestHelper.assert_false(unknown_result, "Unknown setting keys rejected")
+
+	# Test recovery from corrupted settings
+	# Save current state
+	var current_volume = settings_manager.get_setting("master_volume")
+
+	# Reset settings
+	settings_manager.reset_settings_to_defaults()
+
+	# Verify defaults are loaded
+	var default_volume = settings_manager.default_settings["master_volume"]
+	TestHelper.assert_equal(default_volume, settings_manager.get_setting("master_volume"), "Reset to defaults works correctly")
+
+	# Test fallback language loading
+	TestHelper.assert_true(settings_manager.languages_data.has("languages"), "Fallback languages loaded")
+	TestHelper.assert_has_key(settings_manager.languages_data["languages"], "en", "English fallback language available")
+	TestHelper.assert_has_key(settings_manager.languages_data["languages"], "ru", "Russian fallback language available")
+
+func test_reset_functionality():
+	TestHelper.print_step("Reset Functionality")
+
+	# Modify settings
+	settings_manager.set_setting("master_volume", 0.8)
+	settings_manager.set_setting("language", "ru")
+
+	# Reset to defaults
+	settings_manager.reset_settings_to_defaults()
+
+	# Verify reset worked
+	TestHelper.assert_equal(settings_manager.default_settings["master_volume"], settings_manager.get_setting("master_volume"), "Volume reset to default")
+	TestHelper.assert_equal(settings_manager.default_settings["language"], settings_manager.get_setting("language"), "Language reset to default")
+
+	# Test that reset saves automatically
+	TestHelper.assert_file_exists("user://settings.cfg", "Settings file exists after reset")
+
+func test_performance_benchmarks():
+	TestHelper.print_step("Performance Benchmarks")
+
+	# Test settings load performance
+	TestHelper.start_performance_test("load_settings")
+	settings_manager.load_settings()
+	TestHelper.end_performance_test("load_settings", 100.0, "Settings load within 100ms")
+
+	# Test settings save performance
+	TestHelper.start_performance_test("save_settings")
+	settings_manager.save_settings()
+	TestHelper.end_performance_test("save_settings", 50.0, "Settings save within 50ms")
+
+	# Test validation performance
+	TestHelper.start_performance_test("validation")
+	for i in range(100):
+		settings_manager.set_setting("master_volume", 0.5)
+	TestHelper.end_performance_test("validation", 50.0, "100 validations within 50ms")
+
+func cleanup_tests():
+	TestHelper.print_step("Cleanup")
+
+	# Restore original settings
+	if original_settings:
+		settings_manager.settings = original_settings.duplicate(true)
+		settings_manager.save_settings()
+
+	# Clean up temporary files
+	for temp_file in temp_files:
+		TestHelper.cleanup_temp_file(temp_file)
+
+	TestHelper.assert_true(true, "Test cleanup completed")

tests/test_settings_manager.gd.uid

@@ -0,0 +1 @@
+uid://dopm8ivgucbgd

tests/test_tile.gd

@@ -0,0 +1,409 @@
+extends SceneTree
+
+## Test suite for Tile component
+##
+## Tests tile initialization, texture management, and gem types.
+
+const TestHelper = preload("res://tests/helpers/TestHelper.gd")
+
+var tile_scene: PackedScene
+var tile_instance: Node2D
+var test_viewport: SubViewport
+
+func _initialize():
+	# Wait for autoloads to initialize
+	await process_frame
+	await process_frame
+
+	run_tests()
+
+	# Exit after tests complete
+	quit()
+
+func run_tests():
+	TestHelper.print_test_header("Tile Component")
+
+	# Setup test environment
+	setup_test_environment()
+
+	# Run test suites
+	test_basic_functionality()
+	test_tile_constants()
+	test_texture_management()
+	test_gem_type_management()
+	test_visual_feedback_system()
+	test_state_management()
+	test_input_validation()
+	test_scaling_and_sizing()
+	test_memory_safety()
+	test_error_handling()
+
+	# Cleanup
+	cleanup_tests()
+
+	TestHelper.print_test_footer("Tile Component")
+
+func setup_test_environment():
+	TestHelper.print_step("Test Environment Setup")
+
+	# Load Tile scene
+	tile_scene = load("res://scenes/game/gameplays/tile.tscn")
+	TestHelper.assert_not_null(tile_scene, "Tile scene loads successfully")
+
+	# Create test viewport for isolated testing
+	test_viewport = SubViewport.new()
+	test_viewport.size = Vector2i(400, 400)
+	root.add_child(test_viewport)
+
+	# Instance Tile in test viewport
+	if tile_scene:
+		tile_instance = tile_scene.instantiate()
+		test_viewport.add_child(tile_instance)
+		TestHelper.assert_not_null(tile_instance, "Tile instance created successfully")
+
+		# Wait for initialization
+		await process_frame
+		await process_frame
+
+func test_basic_functionality():
+	TestHelper.print_step("Basic Functionality")
+
+	if not tile_instance:
+		TestHelper.assert_true(false, "Tile instance not available for testing")
+		return
+
+	# Test that Tile has expected properties
+	var expected_properties = ["tile_type", "grid_position", "is_selected", "is_highlighted", "original_scale", "active_gem_types"]
+	for prop in expected_properties:
+		TestHelper.assert_true(prop in tile_instance, "Tile has property: " + prop)
+
+	# Test that Tile has expected methods
+	var expected_methods = ["set_active_gem_types", "get_active_gem_count", "add_gem_type", "remove_gem_type", "force_reset_visual_state"]
+	TestHelper.assert_has_methods(tile_instance, expected_methods, "Tile component methods")
+
+	# Test signals
+	TestHelper.assert_true(tile_instance.has_signal("tile_selected"), "Tile has tile_selected signal")
+
+	# Test sprite reference
+	TestHelper.assert_not_null(tile_instance.sprite, "Sprite node is available")
+	TestHelper.assert_true(tile_instance.sprite is Sprite2D, "Sprite is Sprite2D type")
+
+	# Test group membership
+	TestHelper.assert_true(tile_instance.is_in_group("tiles"), "Tile is in 'tiles' group")
+
+func test_tile_constants():
+	TestHelper.print_step("Tile Constants")
+
+	if not tile_instance:
+		return
+
+	# Test TILE_SIZE constant
+	TestHelper.assert_equal(48, tile_instance.TILE_SIZE, "TILE_SIZE constant is correct")
+
+	# Test all_gem_textures array
+	TestHelper.assert_not_null(tile_instance.all_gem_textures, "All gem textures array exists")
+	TestHelper.assert_true(tile_instance.all_gem_textures is Array, "All gem textures is Array type")
+	TestHelper.assert_equal(8, tile_instance.all_gem_textures.size(), "All gem textures has expected count")
+
+	# Test that all gem textures are valid
+	for i in range(tile_instance.all_gem_textures.size()):
+		var texture = tile_instance.all_gem_textures[i]
+		TestHelper.assert_not_null(texture, "Gem texture %d is not null" % i)
+		TestHelper.assert_true(texture is Texture2D, "Gem texture %d is Texture2D type" % i)
+
+func test_texture_management():
+	TestHelper.print_step("Texture Management")
+
+	if not tile_instance:
+		return
+
+	# Test default gem types initialization
+	TestHelper.assert_not_null(tile_instance.active_gem_types, "Active gem types is initialized")
+	TestHelper.assert_true(tile_instance.active_gem_types is Array, "Active gem types is Array type")
+	TestHelper.assert_true(tile_instance.active_gem_types.size() > 0, "Active gem types has content")
+
+	# Test texture assignment for valid tile types
+	var original_type = tile_instance.tile_type
+
+	for i in range(min(3, tile_instance.active_gem_types.size())):
+		tile_instance.tile_type = i
+		TestHelper.assert_equal(i, tile_instance.tile_type, "Tile type set correctly to %d" % i)
+
+		if tile_instance.sprite:
+			TestHelper.assert_not_null(tile_instance.sprite.texture, "Sprite texture assigned for type %d" % i)
+
+	# Restore original type
+	tile_instance.tile_type = original_type
+
+func test_gem_type_management():
+	TestHelper.print_step("Gem Type Management")
+
+	if not tile_instance:
+		return
+
+	# Store original state
+	var original_gem_types = tile_instance.active_gem_types.duplicate()
+
+	# Test set_active_gem_types with valid array
+	var test_gems = [0, 1, 2]
+	tile_instance.set_active_gem_types(test_gems)
+	TestHelper.assert_equal(3, tile_instance.get_active_gem_count(), "Active gem count set correctly")
+
+	# Test add_gem_type
+	var add_result = tile_instance.add_gem_type(3)
+	TestHelper.assert_true(add_result, "Valid gem type added successfully")
+	TestHelper.assert_equal(4, tile_instance.get_active_gem_count(), "Gem count increased after addition")
+
+	# Test adding duplicate gem type
+	var duplicate_result = tile_instance.add_gem_type(3)
+	TestHelper.assert_false(duplicate_result, "Duplicate gem type addition rejected")
+	TestHelper.assert_equal(4, tile_instance.get_active_gem_count(), "Gem count unchanged after duplicate")
+
+	# Test add_gem_type with invalid index
+	var invalid_add = tile_instance.add_gem_type(99)
+	TestHelper.assert_false(invalid_add, "Invalid gem index addition rejected")
+
+	# Test remove_gem_type
+	var remove_result = tile_instance.remove_gem_type(3)
+	TestHelper.assert_true(remove_result, "Valid gem type removed successfully")
+	TestHelper.assert_equal(3, tile_instance.get_active_gem_count(), "Gem count decreased after removal")
+
+	# Test removing non-existent gem type
+	var nonexistent_remove = tile_instance.remove_gem_type(99)
+	TestHelper.assert_false(nonexistent_remove, "Non-existent gem type removal rejected")
+
+	# Test minimum gem types protection
+	tile_instance.set_active_gem_types([0, 1])  # Set to minimum
+	var protected_remove = tile_instance.remove_gem_type(0)
+	TestHelper.assert_false(protected_remove, "Minimum gem types protection active")
+	TestHelper.assert_equal(2, tile_instance.get_active_gem_count(), "Minimum gem count preserved")
+
+	# Restore original state
+	tile_instance.set_active_gem_types(original_gem_types)
+
+func test_visual_feedback_system():
+	TestHelper.print_step("Visual Feedback System")
+
+	if not tile_instance:
+		return
+
+	# Store original state
+	var original_selected = tile_instance.is_selected
+	var original_highlighted = tile_instance.is_highlighted
+
+	# Test selection visual feedback
+	tile_instance.is_selected = true
+	TestHelper.assert_true(tile_instance.is_selected, "Selection state set correctly")
+
+	# Wait for potential animation
+	await process_frame
+
+	if tile_instance.sprite:
+		# Test that modulate is brighter when selected
+		var modulate = tile_instance.sprite.modulate
+		TestHelper.assert_true(modulate.r > 1.0 or modulate.g > 1.0 or modulate.b > 1.0, "Selected tile has brighter modulate")
+
+	# Test highlight visual feedback
+	tile_instance.is_selected = false
+	tile_instance.is_highlighted = true
+	TestHelper.assert_true(tile_instance.is_highlighted, "Highlight state set correctly")
+
+	# Wait for potential animation
+	await process_frame
+
+	# Test normal state
+	tile_instance.is_highlighted = false
+	TestHelper.assert_false(tile_instance.is_highlighted, "Normal state restored")
+
+	# Test force reset
+	tile_instance.is_selected = true
+	tile_instance.is_highlighted = true
+	tile_instance.force_reset_visual_state()
+	TestHelper.assert_false(tile_instance.is_selected, "Force reset clears selection")
+	TestHelper.assert_false(tile_instance.is_highlighted, "Force reset clears highlight")
+
+	# Restore original state
+	tile_instance.is_selected = original_selected
+	tile_instance.is_highlighted = original_highlighted
+
+func test_state_management():
+	TestHelper.print_step("State Management")
+
+	if not tile_instance:
+		return
+
+	# Test initial state
+	TestHelper.assert_true(tile_instance.tile_type >= 0, "Initial tile type is non-negative")
+	TestHelper.assert_true(tile_instance.grid_position is Vector2i, "Grid position is Vector2i type")
+	TestHelper.assert_true(tile_instance.original_scale is Vector2, "Original scale is Vector2 type")
+
+	# Test tile type bounds checking
+	var original_type = tile_instance.tile_type
+	var max_valid_type = tile_instance.active_gem_types.size() - 1
+
+	# Test valid tile type
+	if max_valid_type >= 0:
+		tile_instance.tile_type = max_valid_type
+		TestHelper.assert_equal(max_valid_type, tile_instance.tile_type, "Valid tile type accepted")
+
+	# Test state consistency
+	TestHelper.assert_true(tile_instance.tile_type < tile_instance.active_gem_types.size(), "Tile type within active gems range")
+
+	# Restore original type
+	tile_instance.tile_type = original_type
+
+func test_input_validation():
+	TestHelper.print_step("Input Validation")
+
+	if not tile_instance:
+		return
+
+	# Test empty gem types array
+	var original_gems = tile_instance.active_gem_types.duplicate()
+	tile_instance.set_active_gem_types([])
+	# Should fall back to defaults or maintain previous state
+	TestHelper.assert_true(tile_instance.get_active_gem_count() > 0, "Empty gem array handled gracefully")
+
+	# Test null gem types array
+	tile_instance.set_active_gem_types(null)
+	TestHelper.assert_true(tile_instance.get_active_gem_count() > 0, "Null gem array handled gracefully")
+
+	# Test invalid gem indices in array
+	tile_instance.set_active_gem_types([0, 1, 99, 2])  # 99 is invalid
+	# Should use fallback or filter invalid indices
+	TestHelper.assert_true(tile_instance.get_active_gem_count() > 0, "Invalid gem indices handled gracefully")
+
+	# Test negative gem indices
+	var negative_add = tile_instance.add_gem_type(-1)
+	TestHelper.assert_false(negative_add, "Negative gem index rejected")
+
+	# Test out-of-bounds gem indices
+	var oob_add = tile_instance.add_gem_type(tile_instance.all_gem_textures.size())
+	TestHelper.assert_false(oob_add, "Out-of-bounds gem index rejected")
+
+	# Restore original state
+	tile_instance.set_active_gem_types(original_gems)
+
+func test_scaling_and_sizing():
+	TestHelper.print_step("Scaling and Sizing")
+
+	if not tile_instance:
+		return
+
+	# Test original scale calculation
+	TestHelper.assert_not_null(tile_instance.original_scale, "Original scale is calculated")
+	TestHelper.assert_true(tile_instance.original_scale.x > 0, "Original scale X is positive")
+	TestHelper.assert_true(tile_instance.original_scale.y > 0, "Original scale Y is positive")
+
+	# Test that tile size is respected
+	if tile_instance.sprite and tile_instance.sprite.texture:
+		var texture_size = tile_instance.sprite.texture.get_size()
+		var scaled_size = texture_size * tile_instance.original_scale
+		var max_dimension = max(scaled_size.x, scaled_size.y)
+		TestHelper.assert_true(max_dimension <= tile_instance.TILE_SIZE + 1, "Scaled tile fits within TILE_SIZE")
+
+	# Test scale animation for visual feedback
+	var original_scale = tile_instance.sprite.scale if tile_instance.sprite else Vector2.ONE
+
+	# Test selection scaling
+	tile_instance.is_selected = true
+	await process_frame
+	await process_frame  # Wait for animation
+
+	if tile_instance.sprite:
+		var selected_scale = tile_instance.sprite.scale
+		TestHelper.assert_true(selected_scale.x >= original_scale.x, "Selected tile scale is larger or equal")
+
+	# Reset to normal
+	tile_instance.is_selected = false
+	await process_frame
+	await process_frame
+
+func test_memory_safety():
+	TestHelper.print_step("Memory Safety")
+
+	if not tile_instance:
+		return
+
+	# Test sprite null checking
+	var original_sprite = tile_instance.sprite
+	tile_instance.sprite = null
+
+	# These operations should not crash
+	tile_instance._set_tile_type(0)
+	tile_instance._update_visual_feedback()
+	tile_instance.force_reset_visual_state()
+
+	TestHelper.assert_true(true, "Null sprite operations handled safely")
+
+	# Restore sprite
+	tile_instance.sprite = original_sprite
+
+	# Test valid instance checking in visual updates
+	if tile_instance.sprite:
+		TestHelper.assert_true(is_instance_valid(tile_instance.sprite), "Sprite instance is valid")
+
+	# Test gem types array integrity
+	TestHelper.assert_true(tile_instance.active_gem_types is Array, "Active gem types maintains Array type")
+
+	# Test that gem indices are within bounds
+	for gem_index in tile_instance.active_gem_types:
+		TestHelper.assert_true(gem_index >= 0, "Gem index is non-negative")
+		TestHelper.assert_true(gem_index < tile_instance.all_gem_textures.size(), "Gem index within texture array bounds")
+
+func test_error_handling():
+	TestHelper.print_step("Error Handling")
+
+	if not tile_instance:
+		return
+
+	# Test graceful handling of missing sprite during initialization
+	var backup_sprite = tile_instance.sprite
+	tile_instance.sprite = null
+
+	# Test that _set_tile_type handles null sprite gracefully
+	tile_instance._set_tile_type(0)
+	TestHelper.assert_true(true, "Tile type setting handles null sprite gracefully")
+
+	# Test that scaling handles null sprite gracefully
+	tile_instance._scale_sprite_to_fit()
+	TestHelper.assert_true(true, "Sprite scaling handles null sprite gracefully")
+
+	# Restore sprite
+	tile_instance.sprite = backup_sprite
+
+	# Test invalid tile type handling
+	var original_type = tile_instance.tile_type
+	tile_instance._set_tile_type(-1)  # Invalid negative type
+	tile_instance._set_tile_type(999)  # Invalid large type
+
+	# Should not crash and should maintain reasonable state
+	TestHelper.assert_true(true, "Invalid tile types handled gracefully")
+
+	# Restore original type
+	tile_instance.tile_type = original_type
+
+	# Test array bounds protection
+	var large_gem_types = []
+	for i in range(50):  # Create array larger than texture array
+		large_gem_types.append(i)
+
+	tile_instance.set_active_gem_types(large_gem_types)
+	# Should fall back to safe defaults
+	TestHelper.assert_true(tile_instance.get_active_gem_count() <= tile_instance.all_gem_textures.size(), "Large gem array handled safely")
+
+func cleanup_tests():
+	TestHelper.print_step("Cleanup")
+
+	# Clean up tile instance
+	if tile_instance and is_instance_valid(tile_instance):
+		tile_instance.queue_free()
+
+	# Clean up test viewport
+	if test_viewport and is_instance_valid(test_viewport):
+		test_viewport.queue_free()
+
+	# Wait for cleanup
+	await process_frame
+
+	TestHelper.assert_true(true, "Test cleanup completed")

tests/test_tile.gd.uid

@@ -0,0 +1 @@
+uid://bdn1rf14bqwv4

tests/test_value_stepper.gd

@@ -0,0 +1,412 @@
+extends SceneTree
+
+## Test suite for ValueStepper component
+##
+## Tests data loading, value navigation, and input handling.
+
+const TestHelper = preload("res://tests/helpers/TestHelper.gd")
+
+var stepper_scene: PackedScene
+var stepper_instance: Control
+var test_viewport: SubViewport
+var original_language: String
+
+func _initialize():
+	# Wait for autoloads to initialize
+	await process_frame
+	await process_frame
+
+	run_tests()
+
+	# Exit after tests complete
+	quit()
+
+func run_tests():
+	TestHelper.print_test_header("ValueStepper Component")
+
+	# Store original settings
+	var settings_manager = root.get_node("SettingsManager")
+	original_language = settings_manager.get_setting("language")
+
+	# Setup test environment
+	setup_test_environment()
+
+	# Run test suites
+	test_basic_functionality()
+	test_data_source_loading()
+	test_value_navigation()
+	test_custom_values()
+	test_input_handling()
+	test_visual_feedback()
+	test_settings_integration()
+	test_boundary_conditions()
+	test_error_handling()
+
+	# Cleanup
+	cleanup_tests()
+
+	TestHelper.print_test_footer("ValueStepper Component")
+
+func setup_test_environment():
+	TestHelper.print_step("Test Environment Setup")
+
+	# Load ValueStepper scene
+	stepper_scene = load("res://scenes/ui/components/ValueStepper.tscn")
+	TestHelper.assert_not_null(stepper_scene, "ValueStepper scene loads successfully")
+
+	# Create test viewport for isolated testing
+	test_viewport = SubViewport.new()
+	test_viewport.size = Vector2i(400, 200)
+	root.add_child(test_viewport)
+
+	# Instance ValueStepper in test viewport
+	if stepper_scene:
+		stepper_instance = stepper_scene.instantiate()
+		test_viewport.add_child(stepper_instance)
+		TestHelper.assert_not_null(stepper_instance, "ValueStepper instance created successfully")
+
+		# Wait for initialization
+		await process_frame
+		await process_frame
+
+func test_basic_functionality():
+	TestHelper.print_step("Basic Functionality")
+
+	if not stepper_instance:
+		TestHelper.assert_true(false, "ValueStepper instance not available for testing")
+		return
+
+	# Test that ValueStepper has expected properties
+	var expected_properties = ["data_source", "custom_format_function", "values", "display_names", "current_index"]
+	for prop in expected_properties:
+		TestHelper.assert_true(prop in stepper_instance, "ValueStepper has property: " + prop)
+
+	# Test that ValueStepper has expected methods
+	var expected_methods = ["change_value", "setup_custom_values", "get_current_value", "set_current_value", "set_highlighted", "handle_input_action", "get_control_name"]
+	TestHelper.assert_has_methods(stepper_instance, expected_methods, "ValueStepper component methods")
+
+	# Test signals
+	TestHelper.assert_true(stepper_instance.has_signal("value_changed"), "ValueStepper has value_changed signal")
+
+	# Test UI components
+	TestHelper.assert_not_null(stepper_instance.left_button, "Left button is available")
+	TestHelper.assert_not_null(stepper_instance.right_button, "Right button is available")
+	TestHelper.assert_not_null(stepper_instance.value_display, "Value display label is available")
+
+	# Test UI component types
+	TestHelper.assert_true(stepper_instance.left_button is Button, "Left button is Button type")
+	TestHelper.assert_true(stepper_instance.right_button is Button, "Right button is Button type")
+	TestHelper.assert_true(stepper_instance.value_display is Label, "Value display is Label type")
+
+func test_data_source_loading():
+	TestHelper.print_step("Data Source Loading")
+
+	if not stepper_instance:
+		return
+
+	# Test default language data source
+	TestHelper.assert_equal("language", stepper_instance.data_source, "Default data source is language")
+
+	# Test that values are loaded
+	TestHelper.assert_not_null(stepper_instance.values, "Values array is initialized")
+	TestHelper.assert_not_null(stepper_instance.display_names, "Display names array is initialized")
+	TestHelper.assert_true(stepper_instance.values is Array, "Values is Array type")
+	TestHelper.assert_true(stepper_instance.display_names is Array, "Display names is Array type")
+
+	# Test that language data is loaded correctly
+	if stepper_instance.data_source == "language":
+		TestHelper.assert_true(stepper_instance.values.size() > 0, "Language values loaded")
+		TestHelper.assert_true(stepper_instance.display_names.size() > 0, "Language display names loaded")
+		TestHelper.assert_equal(stepper_instance.values.size(), stepper_instance.display_names.size(), "Values and display names arrays have same size")
+
+		# Test that current language is properly selected
+		var current_lang = root.get_node("SettingsManager").get_setting("language")
+		var expected_index = stepper_instance.values.find(current_lang)
+		if expected_index >= 0:
+			TestHelper.assert_equal(expected_index, stepper_instance.current_index, "Current language index set correctly")
+
+	# Test resolution data source
+	var resolution_stepper = stepper_scene.instantiate()
+	resolution_stepper.data_source = "resolution"
+	test_viewport.add_child(resolution_stepper)
+	await process_frame
+
+	TestHelper.assert_true(resolution_stepper.values.size() > 0, "Resolution values loaded")
+	TestHelper.assert_contains(resolution_stepper.values, "1920x1080", "Resolution data contains expected value")
+
+	resolution_stepper.queue_free()
+
+	# Test difficulty data source
+	var difficulty_stepper = stepper_scene.instantiate()
+	difficulty_stepper.data_source = "difficulty"
+	test_viewport.add_child(difficulty_stepper)
+	await process_frame
+
+	TestHelper.assert_true(difficulty_stepper.values.size() > 0, "Difficulty values loaded")
+	TestHelper.assert_contains(difficulty_stepper.values, "normal", "Difficulty data contains expected value")
+	TestHelper.assert_equal(1, difficulty_stepper.current_index, "Difficulty defaults to normal")
+
+	difficulty_stepper.queue_free()
+
+func test_value_navigation():
+	TestHelper.print_step("Value Navigation")
+
+	if not stepper_instance:
+		return
+
+	# Store original state
+	var original_index = stepper_instance.current_index
+	var original_value = stepper_instance.get_current_value()
+
+	# Test forward navigation
+	var initial_value = stepper_instance.get_current_value()
+	stepper_instance.change_value(1)
+	var next_value = stepper_instance.get_current_value()
+	TestHelper.assert_not_equal(initial_value, next_value, "Forward navigation changes value")
+
+	# Test backward navigation
+	stepper_instance.change_value(-1)
+	var back_value = stepper_instance.get_current_value()
+	TestHelper.assert_equal(initial_value, back_value, "Backward navigation returns to original value")
+
+	# Test wrap-around forward
+	var max_index = stepper_instance.values.size() - 1
+	stepper_instance.current_index = max_index
+	stepper_instance.change_value(1)
+	TestHelper.assert_equal(0, stepper_instance.current_index, "Forward navigation wraps to beginning")
+
+	# Test wrap-around backward
+	stepper_instance.current_index = 0
+	stepper_instance.change_value(-1)
+	TestHelper.assert_equal(max_index, stepper_instance.current_index, "Backward navigation wraps to end")
+
+	# Restore original state
+	stepper_instance.current_index = original_index
+	stepper_instance._update_display()
+
+func test_custom_values():
+	TestHelper.print_step("Custom Values")
+
+	if not stepper_instance:
+		return
+
+	# Store original state
+	var original_values = stepper_instance.values.duplicate()
+	var original_display_names = stepper_instance.display_names.duplicate()
+	var original_index = stepper_instance.current_index
+
+	# Test custom values without display names
+	var custom_values = ["apple", "banana", "cherry"]
+	stepper_instance.setup_custom_values(custom_values)
+
+	TestHelper.assert_equal(3, stepper_instance.values.size(), "Custom values set correctly")
+	TestHelper.assert_equal("apple", stepper_instance.values[0], "First custom value correct")
+	TestHelper.assert_equal(0, stepper_instance.current_index, "Index reset to 0 for custom values")
+	TestHelper.assert_equal("apple", stepper_instance.get_current_value(), "Current value matches first custom value")
+
+	# Test custom values with display names
+	var custom_display_names = ["Red Apple", "Yellow Banana", "Red Cherry"]
+	stepper_instance.setup_custom_values(custom_values, custom_display_names)
+
+	TestHelper.assert_equal(3, stepper_instance.display_names.size(), "Custom display names set correctly")
+	TestHelper.assert_equal("Red Apple", stepper_instance.display_names[0], "First display name correct")
+
+	# Test navigation with custom values
+	stepper_instance.change_value(1)
+	TestHelper.assert_equal("banana", stepper_instance.get_current_value(), "Navigation works with custom values")
+
+	# Test set_current_value
+	stepper_instance.set_current_value("cherry")
+	TestHelper.assert_equal("cherry", stepper_instance.get_current_value(), "set_current_value works correctly")
+	TestHelper.assert_equal(2, stepper_instance.current_index, "Index updated correctly by set_current_value")
+
+	# Test invalid value
+	stepper_instance.set_current_value("grape")
+	TestHelper.assert_equal("cherry", stepper_instance.get_current_value(), "Invalid value doesn't change current value")
+
+	# Restore original state
+	stepper_instance.values = original_values
+	stepper_instance.display_names = original_display_names
+	stepper_instance.current_index = original_index
+	stepper_instance._update_display()
+
+func test_input_handling():
+	TestHelper.print_step("Input Handling")
+
+	if not stepper_instance:
+		return
+
+	# Store original state
+	var original_value = stepper_instance.get_current_value()
+
+	# Test left input action
+	var left_handled = stepper_instance.handle_input_action("move_left")
+	TestHelper.assert_true(left_handled, "Left input action handled")
+	TestHelper.assert_not_equal(original_value, stepper_instance.get_current_value(), "Left action changes value")
+
+	# Test right input action
+	var right_handled = stepper_instance.handle_input_action("move_right")
+	TestHelper.assert_true(right_handled, "Right input action handled")
+	TestHelper.assert_equal(original_value, stepper_instance.get_current_value(), "Right action returns to original value")
+
+	# Test invalid input action
+	var invalid_handled = stepper_instance.handle_input_action("invalid_action")
+	TestHelper.assert_false(invalid_handled, "Invalid input action not handled")
+
+	# Test button press simulation
+	if stepper_instance.left_button:
+		var before_left = stepper_instance.get_current_value()
+		stepper_instance._on_left_button_pressed()
+		TestHelper.assert_not_equal(before_left, stepper_instance.get_current_value(), "Left button press changes value")
+
+	if stepper_instance.right_button:
+		var before_right = stepper_instance.get_current_value()
+		stepper_instance._on_right_button_pressed()
+		TestHelper.assert_equal(original_value, stepper_instance.get_current_value(), "Right button press returns to original")
+
+func test_visual_feedback():
+	TestHelper.print_step("Visual Feedback")
+
+	if not stepper_instance:
+		return
+
+	# Store original visual properties
+	var original_scale = stepper_instance.scale
+	var original_modulate = stepper_instance.modulate
+
+	# Test highlighting
+	stepper_instance.set_highlighted(true)
+	TestHelper.assert_true(stepper_instance.is_highlighted, "Highlighted state set correctly")
+	TestHelper.assert_true(stepper_instance.scale.x > original_scale.x, "Scale increased when highlighted")
+
+	# Test unhighlighting
+	stepper_instance.set_highlighted(false)
+	TestHelper.assert_false(stepper_instance.is_highlighted, "Highlighted state cleared correctly")
+	TestHelper.assert_equal(original_scale, stepper_instance.scale, "Scale restored when unhighlighted")
+	TestHelper.assert_equal(original_modulate, stepper_instance.modulate, "Modulate restored when unhighlighted")
+
+	# Test display update
+	if stepper_instance.value_display:
+		var current_text = stepper_instance.value_display.text
+		TestHelper.assert_true(current_text.length() > 0, "Value display has text content")
+		TestHelper.assert_not_equal("N/A", current_text, "Value display shows valid content")
+
+func test_settings_integration():
+	TestHelper.print_step("Settings Integration")
+
+	if not stepper_instance or stepper_instance.data_source != "language":
+		return
+
+	# Store original language
+	var original_lang = root.get_node("SettingsManager").get_setting("language")
+
+	# Test that changing language stepper updates settings
+	var available_languages = stepper_instance.values
+	if available_languages.size() > 1:
+		# Find a different language
+		var target_lang = null
+		for lang in available_languages:
+			if lang != original_lang:
+				target_lang = lang
+				break
+
+		if target_lang:
+			stepper_instance.set_current_value(target_lang)
+			stepper_instance._apply_value_change(target_lang, stepper_instance.current_index)
+
+			# Verify setting was updated
+			var updated_lang = root.get_node("SettingsManager").get_setting("language")
+			TestHelper.assert_equal(target_lang, updated_lang, "Language setting updated correctly")
+
+			# Restore original language
+			root.get_node("SettingsManager").set_setting("language", original_lang)
+
+func test_boundary_conditions():
+	TestHelper.print_step("Boundary Conditions")
+
+	if not stepper_instance:
+		return
+
+	# Test empty values array
+	var empty_stepper = stepper_scene.instantiate()
+	empty_stepper.data_source = "unknown"  # Will result in empty arrays
+	test_viewport.add_child(empty_stepper)
+	await process_frame
+
+	TestHelper.assert_equal("", empty_stepper.get_current_value(), "Empty values array returns empty string")
+
+	# Test change_value with empty array
+	empty_stepper.change_value(1)  # Should not crash
+	TestHelper.assert_true(true, "change_value handles empty array gracefully")
+
+	empty_stepper.queue_free()
+
+	# Test index bounds
+	if stepper_instance.values.size() > 0:
+		# Test negative index handling
+		stepper_instance.current_index = -1
+		stepper_instance._update_display()
+		TestHelper.assert_equal("N/A", stepper_instance.value_display.text, "Negative index shows N/A")
+
+		# Test out-of-bounds index handling
+		stepper_instance.current_index = stepper_instance.values.size()
+		stepper_instance._update_display()
+		TestHelper.assert_equal("N/A", stepper_instance.value_display.text, "Out-of-bounds index shows N/A")
+
+		# Restore valid index
+		stepper_instance.current_index = 0
+		stepper_instance._update_display()
+
+func test_error_handling():
+	TestHelper.print_step("Error Handling")
+
+	if not stepper_instance:
+		return
+
+	# Test unknown data source
+	var unknown_stepper = stepper_scene.instantiate()
+	unknown_stepper.data_source = "invalid_source"
+	test_viewport.add_child(unknown_stepper)
+	await process_frame
+
+	# Should not crash and should handle gracefully
+	TestHelper.assert_true(true, "Unknown data source handled gracefully")
+	unknown_stepper.queue_free()
+
+	# Test get_control_name
+	var control_name = stepper_instance.get_control_name()
+	TestHelper.assert_true(control_name.ends_with("_stepper"), "Control name has correct suffix")
+	TestHelper.assert_true(control_name.begins_with(stepper_instance.data_source), "Control name includes data source")
+
+	# Test custom values with mismatched arrays
+	var values_3 = ["a", "b", "c"]
+	var names_2 = ["A", "B"]
+	stepper_instance.setup_custom_values(values_3, names_2)
+
+	# Should handle gracefully - display_names should be duplicated from values
+	TestHelper.assert_equal(3, stepper_instance.values.size(), "Values array size preserved")
+	TestHelper.assert_equal(2, stepper_instance.display_names.size(), "Display names size preserved as provided")
+
+	# Test navigation with mismatched arrays
+	stepper_instance.current_index = 2  # Index where display_names doesn't exist
+	stepper_instance._update_display()
+	TestHelper.assert_equal("c", stepper_instance.value_display.text, "Falls back to value when display name missing")
+
+func cleanup_tests():
+	TestHelper.print_step("Cleanup")
+
+	# Restore original language setting
+	root.get_node("SettingsManager").set_setting("language", original_language)
+
+	# Clean up stepper instance
+	if stepper_instance and is_instance_valid(stepper_instance):
+		stepper_instance.queue_free()
+
+	# Clean up test viewport
+	if test_viewport and is_instance_valid(test_viewport):
+		test_viewport.queue_free()
+
+	# Wait for cleanup
+	await process_frame
+
+	TestHelper.assert_true(true, "Test cleanup completed")

tests/test_value_stepper.gd.uid

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+uid://cfofaihfhmh8q