iOS Phase 2: Build Error Resolution Session

Date: November 18, 2025 Session Type: Debugging & Build Fixes Scope: iOS Phase 2 post-merge integration issues PR: #278 - iOS Phase 2 build errors and Firebase initialization

Overview

This session focused on resolving build and runtime errors discovered after merging iOS Phase 2 PRs (#275 TournamentDetailViewModel, #276 TournamentDetailView). The integration testing phase revealed three categories of issues that required iterative debugging and fixes.

Context

Merged PRs

PR #275: TournamentDetailViewModel.swift (Agent 2/AAM)

Firebase Firestore integration
Tournament detail loading, join/leave operations
Transaction-based participant management

PR #276: TournamentDetailView.swift (Agent 1/AAP)

SwiftUI detail screen
Navigation from TournamentListView
UI components for tournament display and actions

Integration Status Pre-Session

✅ Code reviews completed
✅ Integration compatibility verified
✅ Both PRs merged to main
❌ Build errors on iOS framework compilation
❌ Runtime crashes in iOS app

Issues Discovered & Fixed

Issue 1: KMP-NativeCoroutines Plugin Compatibility

Error Message:

NoSuchMethodError: 'void org.gradle.api.provider.Property.convention(Object)'

Symptoms:

iOS framework build failed during KMP compilation
Gradle task :shared:domain:podGenIOS failed
Build worked in previous sessions but broke after dependency updates

Root Cause:

kmp-nativecoroutines plugin version ALPHA-39 incompatible with Kotlin 2.2.21
Plugin uses deprecated Gradle API methods
Version mismatch between Kotlin compiler and coroutines plugin

Solution:

Updated kmp-nativecoroutines to version ALPHA-48 in gradle/libs.versions.toml
ALPHA-48 includes fixes for Kotlin 2.2.x compatibility

Files Changed:

gradle/libs.versions.toml

Learning:

KMP ecosystem requires close version alignment between Kotlin, coroutines plugin, and Gradle
ALPHA versions may have breaking changes between releases
Check plugin compatibility when updating Kotlin versions

Issue 2: Swift Type Conversion Errors (7 Total)

After resolving the build framework issue, Swift compilation revealed multiple type conversion errors in the iOS code.

Error Category A: Unused Value Bindings (2 errors)

Location: TournamentDetailViewModel.swift

Error Messages:

// Line 68
Immutable value 'tournament' was never used; consider replacing with '_' or removing it
 
// Line 139
Immutable value 'tournament' was never used; consider replacing with '_' or removing it

Problem:

guard let tournament = tournament else { return } pattern used
Variable binding created but never referenced in subsequent code
Only needed nil check, not the unwrapped value

Solution:

// Before
guard let tournament = tournament else {
    errorMessage = "Tournament not loaded"
    return
}
 
// After
guard tournament != nil else {
    errorMessage = "Tournament not loaded"
    return
}

Files Changed:

iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailViewModel.swift (lines 68, 139)

Error Category B: Swift Int to Kotlin Int32 Conversion (3 errors)

Location: TournamentDetailViewModel.swift

Error Messages:

// Lines 298, 299, 313
Cannot convert value of type 'Int' to expected argument type 'Int32'

Problem:

Swift Int defaults to platform word size (64-bit on modern iOS)
Kotlin Int is always 32-bit
KMP shared module expects Int32 for Kotlin interop
Direct assignment causes type mismatch

Solution:

// Before
currentParticipants: currentParticipants,
maxParticipants: maxParticipants,
 
// After
currentParticipants: Int32(currentParticipants),
maxParticipants: Int32(maxParticipants),

Files Changed:

iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailViewModel.swift (lines 298, 299, 313)

Pattern:

Always wrap Swift Int in Int32() when passing to Kotlin types
Applies to: participant counts, array sizes, numeric fields from Firebase

Error Category C: KotlinLong to Int64 Conversion (1 error)

Location: TournamentDetailView.swift

Error Message:

// Line 107
Value of type 'KotlinLong?' has no member 'longValue'

Problem:

Attempted to use .longValue property which doesn’t exist
KotlinLong uses .int64Value for Swift interop
Different naming convention than expected

Solution:

// Before
let date = Date(timeIntervalSince1970: Double(timestamp.longValue) / 1000.0)
 
// After
let date = Date(timeIntervalSince1970: Double(timestamp.int64Value) / 1000.0)

Files Changed:

iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailView.swift (line 107)

Pattern:

Use .int64Value for KotlinLong → Swift Int64 conversion
Use .int32Value for KotlinInt → Swift Int32 conversion

Error Category D: Property Name Mismatch (1 error)

Location: TournamentDetailView.swift

Error Message:

// Line 181
Value of type 'Tournament' has no member 'public_'

Problem:

Kotlin property isPublic: Boolean
Swift code tried to access public_ (old naming convention)
Property name changed in shared module but iOS code not updated

Solution:

// Before
if tournament.public_ {
    // ...
}
 
// After
if tournament.isPublic {
    // ...
}

Files Changed:

iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailView.swift (line 181)

Pattern:

Check Kotlin property names in shared module when accessing from Swift
Kotlin isPublic → Swift isPublic (no underscore suffix)

Issue 3: Firebase Initialization Issues

After fixing all build errors, runtime testing revealed Firebase initialization crashes.

Error Message (Runtime):

Fatal error: Failed to get FirebaseApp instance. Please call FirebaseApp.configure() before using Firebase.

Symptoms:

App launched successfully
Crash when navigating to TournamentListView
Firestore queries attempted before Firebase initialization

Root Cause Analysis:

Problem 1: Missing GoogleService-Info.plist

File required for Firebase iOS SDK configuration
Contains API keys, project ID, bundle ID mappings
Gitignored for security (not in repository)
Each developer needs their own copy

Problem 2: Improper initialization logic in ArcheryApprenticeApp.swift

// Original (WRONG)
guard let _ = FirebaseApp.app() else {
    print("⚠️ Firebase not configured")
    return AnyView(Text("Firebase not configured"))
}
// Execution stops here if Firebase not configured
// WindowGroup never reached

Problem 3: No graceful fallback in ViewModels

TournamentListViewModel immediately queries Firestore
TournamentDetailViewModel immediately queries Firestore
No check for Firebase availability
Caused crashes when Firebase not configured

Solutions Applied:

Fix 1: Updated ArcheryApprenticeApp.swift initialization logic

// New (CORRECT)
@main
struct ArcheryApprenticeApp: App {
    init() {
        if FirebaseApp.app() == nil {
            FirebaseApp.configure()
        }
    }
 
    var body: some Scene {
        WindowGroup {
            if FirebaseApp.app() != nil {
                ContentView()
            } else {
                VStack {
                    Text("⚠️ Firebase Configuration Required")
                    // ... instructions
                }
            }
        }
    }
}

Changes:

Use if/else instead of guard/return
Allow WindowGroup to render regardless of Firebase status
Show configuration instructions if Firebase not available
App remains functional (doesn’t crash)

Fix 2: Added Firebase availability checks in ViewModels

TournamentListViewModel.swift:

func loadTournaments() {
    guard FirebaseApp.app() != nil else {
        self.errorMessage = "Firebase not configured. Add GoogleService-Info.plist to project."
        self.isLoading = false
        return
    }
 
    // Proceed with Firestore query...
}

TournamentDetailViewModel.swift:

func loadTournamentDetails() {
    guard FirebaseApp.app() != nil else {
        self.errorMessage = "Firebase not configured. Add GoogleService-Info.plist to project."
        self.isLoading = false
        return
    }
 
    // Proceed with Firestore query...
}

Benefits:

Graceful error messages instead of crashes
Users see clear instructions
App remains usable for non-Firebase features
Developers can run app without Firebase setup

Files Changed:

iosApp/ArcheryApprentice/ArcheryApprentice/ArcheryApprenticeApp.swift
iosApp/ArcheryApprentice/ArcheryApprentice/TournamentListViewModel.swift
iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailViewModel.swift

Documentation Created:

Firebase setup instructions in error message UI
Developer guide entry (see ios-firebase-setup)

Summary of Changes

Files Modified (9 total)

Gradle Configuration:

gradle/libs.versions.toml - Updated kmp-nativecoroutines to ALPHA-48

iOS Swift Files: 2. iosApp/ArcheryApprentice/ArcheryApprentice/ArcheryApprenticeApp.swift - Firebase init logic 3. iosApp/ArcheryApprentice/ArcheryApprentice/TournamentListViewModel.swift - Firebase availability check 4. iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailViewModel.swift - Type conversions + Firebase checks 5. iosApp/ArcheryApprentice/ArcheryApprentice/TournamentDetailView.swift - Type conversions + property names

Build Status

Before Session:

❌ iOS framework build: FAILED (KMP plugin error)
❌ Swift compilation: FAILED (7 type errors)
❌ Runtime: CRASHED (Firebase not initialized)

After Session:

✅ iOS framework build: SUCCESS
✅ Swift compilation: SUCCESS (all 7 errors fixed)
✅ Runtime: GRACEFUL (shows Firebase config instructions)

Testing Performed

Build Verification:
- Clean build with ./gradlew clean build
- iOS framework generation successful
- Xcode compilation successful
Runtime Testing (Firebase not configured):
- App launches successfully
- Shows Firebase configuration message
- No crashes
- Graceful error handling
Integration Points Verified:
- Navigation from TournamentListView works
- TournamentDetailView renders correctly
- Type conversions working (Swift ↔ Kotlin)

Key Learnings

Swift-Kotlin Type Interoperability

Type Mapping Patterns:

// Kotlin → Swift
KotlinInt     → Int32  (use .int32Value)
KotlinLong    → Int64  (use .int64Value)
Kotlin String → String (direct)
Kotlin Boolean→ Bool   (direct)
 
// Swift → Kotlin (for Shared module)
Swift Int     → Int32  (wrap with Int32())
Swift Int64   → Long   (wrap with KotlinLong(longLong:))
Swift String  → String (direct)
Swift Bool    → Boolean(direct)

Property Access:

Kotlin isPublic: Boolean → Swift isPublic (no underscore)
Kotlin public: Boolean → Swift public_ (keyword collision, suffix added)

See: kotlin-swift-type-mappings

Firebase iOS Setup Requirements

Required Files:

GoogleService-Info.plist - Must be in Xcode project
Firebase SDK dependencies - In Podfile/SPM
Initialization code - In app entry point

Best Practices:

Check Firebase availability before Firestore queries
Provide clear error messages for missing configuration
Don’t crash if Firebase not configured
Allow app to run in degraded mode

See: ios-firebase-setup

KMP Plugin Version Management

Critical Dependencies:

Kotlin compiler version
kmp-nativecoroutines plugin version
Gradle version
Must maintain compatibility across all three

When Updating Kotlin:

Check kmp-nativecoroutines release notes
Update plugin to compatible ALPHA version
Test iOS framework build
Document version combinations that work

week-28-ios-firebase-integration - Architecture decisions
kotlin-swift-interop - Interop patterns and best practices
ios-firebase-setup - Firebase configuration guide

Follow-Up Items

Add GoogleService-Info.plist template to repository
Create developer onboarding doc for iOS setup
Document working Kotlin + kmp-nativecoroutines version combinations
Consider CI check for Swift type conversions

References

Main PR: #278 - iOS Phase 2 build errors and Firebase initialization
Phase 2 PRs: #275 (ViewModel), #276 (View)
Branch: fix/ios-phase2-build-errors

Archery Apprentice Documentation

Explorer

iOS Phase 2: Build Error Resolution Session

iOS Phase 2: Build Error Resolution Session

Overview

Context

Merged PRs

Integration Status Pre-Session

Issues Discovered & Fixed

Issue 1: KMP-NativeCoroutines Plugin Compatibility

Issue 2: Swift Type Conversion Errors (7 Total)

Error Category A: Unused Value Bindings (2 errors)

Error Category B: Swift Int to Kotlin Int32 Conversion (3 errors)

Error Category C: KotlinLong to Int64 Conversion (1 error)

Error Category D: Property Name Mismatch (1 error)

Issue 3: Firebase Initialization Issues

Summary of Changes

Files Modified (9 total)

Build Status

Testing Performed

Key Learnings

Swift-Kotlin Type Interoperability

Firebase iOS Setup Requirements

KMP Plugin Version Management

Follow-Up Items

References

Graph View

Table of Contents

Backlinks

Archery Apprentice Documentation

Explorer

iOS Phase 2: Build Error Resolution Session

iOS Phase 2: Build Error Resolution Session

Overview

Context

Merged PRs

Integration Status Pre-Session

Issues Discovered & Fixed

Issue 1: KMP-NativeCoroutines Plugin Compatibility

Issue 2: Swift Type Conversion Errors (7 Total)

Error Category A: Unused Value Bindings (2 errors)

Error Category B: Swift Int to Kotlin Int32 Conversion (3 errors)

Error Category C: KotlinLong to Int64 Conversion (1 error)

Error Category D: Property Name Mismatch (1 error)

Issue 3: Firebase Initialization Issues

Summary of Changes

Files Modified (9 total)

Build Status

Testing Performed

Key Learnings

Swift-Kotlin Type Interoperability

Firebase iOS Setup Requirements

KMP Plugin Version Management

Related Documentation

Follow-Up Items

References

Graph View

Table of Contents

Backlinks