SolPan Testing Strategy

Overview

SolPan follows comprehensive testing practices ensuring code quality, reliability, and maintainability. This document outlines the testing strategy, frameworks, and best practices used throughout the project.

Testing Pyramid

                    ▲
                   ╱ ╲
                  ╱   ╲  E2E Tests (5%)
                 ╱     ╲ - User journeys
                ╱───────╲- Critical paths
               ╱         ╲
              ╱ ╱ ╱ ╱ ╱ ╱ ╲  Integration Tests (15%)
             ╱ ╱ ╱ ╱ ╱ ╱   ╲ - Component interactions
            ╱ ╱ ╱ ╱ ╱ ╱     ╲- API contracts
           ╱───────────────────╲
          ╱   Unit Tests (80%)   ╲
         ╱  - Business logic      ╲
        ╱   - Utilities            ╲
       ╱    - ViewModels            ╲

Unit Tests

Current Coverage

Test Files: 6 Test Cases: 34+ Coverage Target: 85%+ for domain logic

Test Files Location:

app/src/test/java/app/mobilemobile/solpan/
├── SolPanViewModelTest.kt          (Core ViewModel)
├── TutorialFlowTest.kt              (Tutorial logic)
├── model/AlignmentStateTest.kt       (Data model)
├── util/FormattingExtensionsTest.kt (String utilities)
└── solar/SolarCalculatorTest.kt      (Solar calculations)

ViewModel Testing

@RunWith(RobolectricTestRunner::class)
class SolPanViewModelTest {
    
    @get:Rule
    val instantTaskExecutorRule = InstantTaskExecutorRule()
    
    private lateinit var viewModel: SolPanViewModel
    private val fakeLocationRepository = FakeLocationRepository()
    private val fakePreferences = FakeUserPreferencesRepository()
    private val fakeAnalytics = FakeAnalyticsTracker()
    
    @Before
    fun setup() {
        viewModel = SolPanViewModel(
            mode = TiltMode.REALTIME,
            userPreferencesRepository = fakePreferences,
            locationRepository = fakeLocationRepository,
            analyticsTracker = fakeAnalytics,
        )
    }
    
    @Test
    fun optimalParametersUpdatesWhenLocationChanges() = runTest {
        // Arrange
        val testLocation = LocationData(51.5074, -0.1278, 0.0)
        
        // Act
        fakeLocationRepository.setLocation(testLocation)
        advanceUntilIdle()
        
        // Assert
        val parameters = viewModel.optimalPanelParameters.first()
        assertNotNull(parameters)
        assertEquals(51.5074, parameters!!.latitude, 0.0001)
    }
    
    @Test
    fun optimalParametersNullWhenLocationDenied() = runTest {
        // Arrange: No location provided
        
        // Act
        advanceUntilIdle()
        
        // Assert
        val parameters = viewModel.optimalPanelParameters.first()
        assertNull(parameters)
    }
}

Unit Test Best Practices

✅ Do:

// Use descriptive test names
@Test
fun `optimalParameters updates when location changes`()

// Test one behavior per test
@Test
fun `viewModel handles null location gracefully`()

// Use fake implementations for dependencies
val fakeLocationRepository = FakeLocationRepository()

// Test the public API contract
assertEquals(expected, viewModel.optimalPanelParameters.first())

// Use coroutine testing utilities
runTest { ... }
advanceUntilIdle()

❌ Don't:

// Avoid vague names
@Test
fun testViewModel()

// Don't test multiple behaviors
@Test
fun `location and orientation and tilt mode all update`()

// Don't use mocking when fakes work
val mockRepository = mock<LocationRepository>()

// Don't test private implementation details
viewModel.internalCalculatePosition()

Integration Tests

Component Interaction Testing

Not fully implemented yet. Future roadmap includes:

@RunWith(AndroidTestRunner::class)
class SolPanScreenIntegrationTest {
    
    @get:Rule
    val composeTestRule = createComposeRule()
    
    @Test
    fun navigationBetweenModesPreservesState() {
        // Create ViewModel
        val viewModel = SolPanViewModel(...)
        
        // Render with test harness
        composeTestRule.setContent {
            SolPanTheme {
                SolPanApp(viewModel)
            }
        }
        
        // Click on different mode
        composeTestRule.onNodeWithTag("SUMMER_MODE_BUTTON").performClick()
        
        // Verify navigation
        composeTestRule.onNodeWithText("Summer Mode Selected").assertExists()
    }
}

Screenshot Tests

Visual Regression Testing

Current Status: Tests compile but framework discovery issue

Location: app/src/screenshotTest/kotlin/

@Composable
fun CardScreenshotTest() {
    // Preview for screenshot testing
    SolPanTheme {
        Surface {
            AzimuthAwareBubbleLevel(
                currentPitch = 45.0,
                currentRoll = 10.0,
                targetPitch = 35.0,
                currentAzimuth = 120.0,
                targetAzimuth = 135.0,
            )
        }
    }
}

Update Reference Images:

./gradlew :app:updateDebugScreenshotTest

Validate Changes:

./gradlew :app:validateDebugScreenshotTest

Test Data & Fixtures

Fake Implementations

// In app/src/test/
class FakeMagneticDeclinationProvider : MagneticDeclinationProvider {
    override fun getDeclination(latitude: Double, longitude: Double, altitude: Double): Float? {
        return 10f  // Fixed value for testing
    }
}

class FakeLocationRepository : LocationRepository {
    private var testLocation: LocationData? = null
    
    override val locationFlow: Flow<LocationData?> = flow {
        emit(testLocation)
    }
    
    fun setLocation(location: LocationData) {
        testLocation = location
    }
}

class FakeUserPreferencesRepository : UserPreferencesRepository {
    override val userPreferencesFlow: Flow<UserPreferences> = flow {
        emit(UserPreferences(selectedTiltMode = TiltMode.REALTIME))
    }
}

Test Data Builder Pattern

// In test files
fun createTestLocationData(
    latitude: Double = 51.5074,
    longitude: Double = -0.1278,
    altitude: Double = 0.0,
): LocationData {
    return LocationData(latitude, longitude, altitude)
}

fun createTestOptimalPanelParameters(
    azimuth: Double = 180.0,
    pitch: Double = 51.0,
): OptimalPanelParameters {
    return OptimalPanelParameters(azimuth, pitch)
}

Test Execution

Run All Tests

./gradlew :app:testDebugUnitTest

Run Specific Test

./gradlew :app:testDebugUnitTest --tests "app.mobilemobile.solpan.SolPanViewModelTest"

With Coverage Report

./gradlew :app:testDebugUnitTest --tests "..." --coverage
# Report: build/coverage/index.html

Watch Mode (TDD)

./gradlew :app:testDebugUnitTest --watch
# Re-runs on every source change

Testing Tools & Libraries

Current Tools

Tool	Version	Purpose
JUnit	4.13.2	Unit testing framework
Robolectric	Implicit	Android framework simulation
Coroutines Test	1.10.2	Coroutine testing utilities
Truth	Latest	Fluent assertions

Recommended Additions

Turbine (Flow testing): app.cash.turbine:turbine:1.x
MockK (Kotlin mocking): io.mockk:mockk:1.x
Kotest (More assertions): io.kotest:kotest-*:5.x

Accessibility Testing

Automated A11y Tests

Future implementation:

@Test
fun allUIElementsHaveContentDescriptions() {
    composeTestRule.setContent {
        SolPanApp()
    }
    
    // Verify no unlabeled elements
    composeTestRule.onRoot().printToLog("A11Y_CHECK")
    // Parse output for missing descriptions
}

Manual A11y Testing

Enable TalkBack (Settings → Accessibility → TalkBack)
Navigate app with gestures
Verify all information is accessible
Test text scaling (up to 200%)
Verify color contrast (WCAG AAA: 7:1 ratio)

Performance Testing

Benchmarking

Measure solar calculation:

@Test
fun solarCalculationPerformance() {
    val startNs = System.nanoTime()
    
    repeat(1000) {
        SolarCalculator.getSolarPosition(
            latitude = 51.5074,
            longitude = -0.1278,
            date = Calendar.getInstance()
        )
    }
    
    val elapsedNs = System.nanoTime() - startNs
    val avgMs = elapsedNs / 1_000_000 / 1000
    
    // Expect < 5ms per calculation
    assertTrue(avgMs < 5)
}

Future: Jetpack Benchmark:

dependencies {
    androidTestImplementation("androidx.benchmark:benchmark-junit4:1.2.0")
}

Continuous Integration

GitHub Actions Test Execution

- name: Run tests
  run: ./gradlew :app:testDebugUnitTest

- name: Generate coverage report
  run: ./gradlew :app:testDebugUnitTest --coverage

- name: Upload coverage to Codecov
  uses: codecov/codecov-action@v3

Test Execution Matrix

Future: Multi-device testing

strategy:
  matrix:
    api-level: [26, 30, 33, 37]
    arch: [x86, x86_64]
    include:
      - api-level: 37
        arch: arm64-v8a

Test Metrics & Reporting

Current Metrics

Total Test Cases: 34
Pass Rate: 100%
Execution Time: ~2 seconds
Code Coverage: TBD (add coverage plugin)

Coverage Goals

Area	Target	Current
ViewModel	90%	TBD
Domain Logic	85%	TBD
Utilities	80%	TBD
UI Components	60%	TBD (screenshots)

Flaky Test Prevention

Strategies

Avoid Timing Dependencies: Use advanceUntilIdle() instead of Thread.sleep()
Isolate External Services: Mock Fused Location Provider, Firebase, etc.
Deterministic Randomness: Use fixed seeds for random data generation
Resource Cleanup: Use @Before/@After for setup/teardown

Example: Handling Async

// ❌ Flaky: Timing dependent
@Test
fun locationUpdatesUI() {
    Thread.sleep(100)
    assertEquals(expectedLocation, uiState.location)
}

// ✅ Reliable: Uses coroutine testing utils
@Test
fun locationUpdatesUI() = runTest {
    fakeLocationRepository.emitLocation(testLocation)
    advanceUntilIdle()  // Wait for all pending work
    assertEquals(expectedLocation, uiState.location)
}

Testing Philosophy

"Test the contract, not the implementation"

Focus on public API behavior
Avoid testing private methods
Test error cases and edge cases
Use real dependencies where possible (not all mocks)

"Every feature starts with a test"

Write test first (TDD)
Then implement feature
Then refactor with confidence

"Tests are documentation"

Descriptive test names explain expected behavior
Test code shows how to use public API
Comments explain "why", not "what"

Testing Roadmap

Priority order:

✅ Unit tests (complete for core logic)
⏳ Integration tests (ViewModel + Repository interactions)
⏳ UI tests (Navigation, permission flow)
⏳ Screenshot regression tests (Visual consistency)
⏳ Performance benchmarks (TTID, calculation speed)
⏳ Accessibility tests (Automated a11y checks)
⏳ E2E tests (Critical user journeys)

Resources

Summary

SolPan implements comprehensive testing:

34+ unit tests covering core logic
100% pass rate with reliable tests
~2 second execution time
Dependency injection for testability
Fake implementations for isolation
Ready for expansion with integration/E2E tests

Tests ensure reliability, enable refactoring with confidence, and serve as living documentation of expected behavior.

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