Banana Image MCP

""" Property-based tests for ModelSelector. **Feature: service-layer-refactoring** **Validates: Requirements 8.3** This module tests: - Property 9: Model Selection """ from unittest.mock import Mock from hypothesis import HealthCheck, given, settings from hypothesis import strategies as st import pytest from banana_image_mcp.config.settings import ModelSelectionConfig, ModelTier from banana_image_mcp.services.base_image_service import BaseImageService from banana_image_mcp.services.model_selector import ModelSelector # ============================================================================= # Hypothesis Strategies # ============================================================================= # Strategy for generating prompts prompt_strategy = st.text(min_size=1, max_size=200) # Strategy for model tiers model_tier_strategy = st.sampled_from([ModelTier.FLASH, ModelTier.PRO, ModelTier.AUTO, None]) # ============================================================================= # Property 9: Model Selection # ============================================================================= class TestModelSelection: """ **Feature: service-layer-refactoring, Property 9: Model Selection** *For any* prompt and model tier request: - Explicit FLASH request SHALL return FlashImageService - Explicit PRO request SHALL return ProImageService - AUTO request SHALL return a service based on prompt analysis - The returned service SHALL be an instance of BaseImageService """ @pytest.fixture def mock_flash_service(self): """Create a mock Flash service.""" service = Mock(spec=BaseImageService) service.name = "flash" return service @pytest.fixture def mock_pro_service(self): """Create a mock Pro service.""" service = Mock(spec=BaseImageService) service.name = "pro" return service @pytest.fixture def selection_config(self): """Create a selection config.""" return ModelSelectionConfig( default_tier=ModelTier.FLASH, auto_quality_keywords=["professional", "high-quality", "detailed", "4k"], auto_speed_keywords=["quick", "fast", "draft", "prototype"], ) @pytest.fixture def model_selector(self, mock_flash_service, mock_pro_service, selection_config): """Create a ModelSelector for testing.""" return ModelSelector( flash_service=mock_flash_service, pro_service=mock_pro_service, selection_config=selection_config, ) @given(prompt=prompt_strategy) @settings( max_examples=50, suppress_health_check=[HealthCheck.function_scoped_fixture], ) def test_explicit_flash_returns_flash_service( self, model_selector, mock_flash_service, prompt: str ): """ **Feature: service-layer-refactoring, Property 9: Model Selection** Explicit FLASH request should return Flash service. """ service, tier = model_selector.select_model( prompt=prompt, requested_tier=ModelTier.FLASH, ) assert service is mock_flash_service assert tier == ModelTier.FLASH @given(prompt=prompt_strategy) @settings( max_examples=50, suppress_health_check=[HealthCheck.function_scoped_fixture], ) def test_explicit_pro_returns_pro_service(self, model_selector, mock_pro_service, prompt: str): """ **Feature: service-layer-refactoring, Property 9: Model Selection** Explicit PRO request should return Pro service. """ service, tier = model_selector.select_model( prompt=prompt, requested_tier=ModelTier.PRO, ) assert service is mock_pro_service assert tier == ModelTier.PRO @given(prompt=prompt_strategy) @settings( max_examples=50, suppress_health_check=[HealthCheck.function_scoped_fixture], ) def test_auto_returns_valid_service( self, model_selector, mock_flash_service, mock_pro_service, prompt: str ): """ **Feature: service-layer-refactoring, Property 9: Model Selection** AUTO request should return a valid service. """ service, tier = model_selector.select_model( prompt=prompt, requested_tier=ModelTier.AUTO, ) # Should return one of the services assert service in [mock_flash_service, mock_pro_service] assert tier in [ModelTier.FLASH, ModelTier.PRO] @given(prompt=prompt_strategy) @settings( max_examples=50, suppress_health_check=[HealthCheck.function_scoped_fixture], ) def test_none_tier_returns_valid_service( self, model_selector, mock_flash_service, mock_pro_service, prompt: str ): """ **Feature: service-layer-refactoring, Property 9: Model Selection** None tier should behave like AUTO. """ service, tier = model_selector.select_model( prompt=prompt, requested_tier=None, ) # Should return one of the services assert service in [mock_flash_service, mock_pro_service] assert tier in [ModelTier.FLASH, ModelTier.PRO] def test_quality_keywords_favor_pro(self, model_selector, mock_pro_service): """ **Feature: service-layer-refactoring, Property 9: Model Selection** Quality keywords should favor Pro model. """ prompt = "Create a professional high-quality 4k image" service, tier = model_selector.select_model( prompt=prompt, requested_tier=ModelTier.AUTO, ) assert service is mock_pro_service assert tier == ModelTier.PRO def test_speed_keywords_favor_flash(self, model_selector, mock_flash_service): """ **Feature: service-layer-refactoring, Property 9: Model Selection** Speed keywords should favor Flash model. """ prompt = "quick draft prototype image" service, tier = model_selector.select_model( prompt=prompt, requested_tier=ModelTier.AUTO, ) assert service is mock_flash_service assert tier == ModelTier.FLASH def test_4k_resolution_requires_pro(self, model_selector, mock_pro_service): """ **Feature: service-layer-refactoring, Property 9: Model Selection** 4K resolution should require Pro model. """ service, tier = model_selector.select_model( prompt="simple image", requested_tier=ModelTier.AUTO, resolution="4k", ) assert service is mock_pro_service assert tier == ModelTier.PRO def test_grounding_favors_pro(self, model_selector, mock_pro_service): """ **Feature: service-layer-refactoring, Property 9: Model Selection** Grounding should favor Pro model. """ service, tier = model_selector.select_model( prompt="simple image", requested_tier=ModelTier.AUTO, enable_grounding=True, ) assert service is mock_pro_service assert tier == ModelTier.PRO def test_get_model_info_flash(self, model_selector): """ **Feature: service-layer-refactoring, Property 9: Model Selection** get_model_info should return Flash info. """ info = model_selector.get_model_info(ModelTier.FLASH) assert info["tier"] == "flash" assert "Flash" in info["name"] assert info["emoji"] == "⚡" def test_get_model_info_pro(self, model_selector): """ **Feature: service-layer-refactoring, Property 9: Model Selection** get_model_info should return Pro info. """ info = model_selector.get_model_info(ModelTier.PRO) assert info["tier"] == "pro" assert "Pro" in info["name"] assert info["emoji"] == "🏆"