ISSUE-CU06-002: Testing for Claim Prize Functionality

[davidmelendez]

ISSUE-CU06-002: Testing for Claim Prize Functionality

✨ Issue Request

Implement complete unit and integration test suite for the prize claiming functionality (CU-06), covering all use cases and error scenarios.

📌 Description

This issue focuses exclusively on implementing tests for the ClaimPrize functionality of use case CU-06. It is separated from the main implementation issue (SL-CU06-001) to facilitate development during the hackathon. Tests should run with Starknet Foundry (snforge) and cover both successful cases and error scenarios.

🛠️ Steps to Reproduce (if applicable)

Prerequisites:

1. Issue SL-CU06-001 must be completed and implemented
2. The ClaimPrize function must be operational in Lottery.cairo
3. The prize distribution system (CU-05) must be functional

🖼️ Screenshots (if applicable)

Not applicable for testing.

🎯 Expected Behavior

The test suite should cover:

Unit Tests (Cairo - snforge):

1. 🔹 Basic successful claim test

   • Setup: finalized draw, completed distribution, ticket with assigned prize
   • Execute: ClaimPrize(drawId, ticketId)
   • Verify: tokens transferred, ticket.claimed = true, event emitted

2. 🔹 Ownership validation test

   • Try to claim another player's ticket prize
   • Verify: transaction reverts with 'Not ticket owner'

3. 🔹 Double claim test

   • Claim prize successfully
   • Try to claim same ticket again
   • Verify: transaction reverts with 'Prize already claimed'

4. 🔹 No assigned prize test

   • Ticket without prize (prize_assigned = false)
   • Try to claim
   • Verify: transaction reverts with 'No prize assigned'

5. 🔹 No prize amount test

   • Ticket with prize_assigned = true but prize_amount = 0
   • Try to claim
   • Verify: transaction reverts with 'No prize amount'

6. 🔹 Draw not finalized test

   • Draw with isActive = true
   • Try to claim prize
   • Verify: transaction reverts with 'Draw still active'

7. 🔹 Distribution not completed test

   • Finalized draw but distribution_done = false
   • Try to claim prize
   • Verify: transaction reverts with 'Distribution not done'

8. 🔹 Nonexistent draw test

   • Try to claim with non-existent drawId
   • Verify: transaction reverts with 'Draw is not active'

9. 🔹 Reentrancy protection test

   • Simulate reentrancy attack on ClaimPrize
   • Verify: reentrancy guard prevents attack

10. 🔹 Insufficient vault balance test

    • Vault with balance less than prize
    • Try to claim prize
    • Verify: transaction reverts with 'Transfer failed'

11. 🔹 Multiple claims test

    • Several tickets with assigned prizes
    • Claim all successfully
    • Verify: each claim correct, balances updated

12. 🔹 Event emission test

    • Claim prize successfully
    • Verify: PrizeClaimed event with correct fields (drawId, player, ticketId, prizeAmount)

Integration Tests (Cairo - snforge):

1. 🔹 Complete CU-05 → CU-06 flow test

   • Create draw, buy tickets
   • Execute DrawNumbers
   • Execute DistributePrizes
   • Claim prizes from multiple winners
   • Verify: consistent end state

2. 🔹 Different prize levels test

   • Tickets with 1, 2, 3, 4 matches
   • Distribute prizes
   • Claim each level
   • Verify: correct amounts according to percentages

3. 🔹 Token balances test

   • Setup with known initial balances
   • Execute complete flow until claim
   • Verify: correct final balances of players and vault

🚀 Suggested Solution / Feature Request

Test file structure:

Create file: packages/snfoundry/contracts/tests/test_CU06_claim_prize.cairo

use snforge_std::{declare, ContractClassTrait, start_prank, stop_prank, CheatTarget};
use starknet::{ContractAddress, contract_address_const};

// Successful claim test
#[test]
fn test_claim_prize_success() {
    // Setup: deploy contracts, create draw, buy ticket, distribute prizes
    // Execute: ClaimPrize
    // Assert: ticket.claimed = true, balance updated, event emitted
}

// Double claim test
#[test]
#[should_panic(expected: ('Prize already claimed',))]
fn test_claim_prize_already_claimed() {
    // Setup: claim prize once
    // Execute: try to claim again
    // Should panic
}

// No ownership test
#[test]
#[should_panic(expected: ('Not ticket owner',))]
fn test_claim_prize_not_owner() {
    // Setup: ticket owned by player1
    // Execute: player2 tries to claim
    // Should panic
}

// Active draw test
#[test]
#[should_panic(expected: ('Draw still active',))]
fn test_claim_prize_draw_active() {
    // Setup: draw with isActive = true
    // Execute: try to claim
    // Should panic
}

// Distribution not completed test
#[test]
#[should_panic(expected: ('Distribution not done',))]
fn test_claim_prize_distribution_not_done() {
    // Setup: draw finalized but distribution_done = false
    // Execute: try to claim
    // Should panic
}

// No assigned prize test
#[test]
#[should_panic(expected: ('No prize assigned',))]
fn test_claim_prize_no_prize_assigned() {
    // Setup: ticket with prize_assigned = false
    // Execute: try to claim
    // Should panic
}

// No prize amount test
#[test]
#[should_panic(expected: ('No prize amount',))]
fn test_claim_prize_no_amount() {
    // Setup: ticket with prize_amount = 0
    // Execute: try to claim
    // Should panic
}

// PrizeClaimed event test
#[test]
fn test_claim_prize_event_emission() {
    // Setup: valid claim scenario
    // Execute: ClaimPrize
    // Assert: PrizeClaimed event with correct fields
}

// Multiple claims test
#[test]
fn test_claim_multiple_prizes() {
    // Setup: multiple tickets with prizes
    // Execute: claim all prizes
    // Assert: all claimed successfully
}

// Full flow test
#[test]
fn test_full_flow_distribute_and_claim() {
    // Setup: complete lottery flow
    // Execute: BuyTicket -> DrawNumbers -> DistributePrizes -> ClaimPrize
    // Assert: end state consistent
}

Create file: packages/snfoundry/contracts/tests/test_CU06_integration.cairo

Integration tests that validate:

• Interaction between Lottery, StarkPlayERC20 and StarkPlayVault
• Complete flow of multiple players claiming prizes
• Final balance validation
• Performance with large number of tickets

Testing helpers:

Add helper functions in tests:

// Helper for complete setup
fn setup_claim_scenario() -> (
    ContractAddress, // lottery
    ContractAddress, // token
    ContractAddress, // vault
    u64, // drawId
    felt252, // ticketId
    ContractAddress, // player
) {
    // Deploy contracts
    // Create draw
    // Buy ticket
    // Finalize draw
    // Distribute prizes
    // Return addresses and IDs
}

// Helper to verify ticket state
fn assert_ticket_state(
    lottery: ContractAddress,
    drawId: u64,
    ticketId: felt252,
    expected_claimed: bool,
    expected_prize_amount: u256,
) {
    // Read ticket
    // Assert claimed status
    // Assert prize amount
}

// Helper to verify token balance
fn assert_token_balance(
    token: ContractAddress,
    account: ContractAddress,
    expected_balance: u256,
) {
    // Read balance
    // Assert equals expected
}

Commands to run tests:

# Run all CU06 tests
cd packages/snfoundry/contracts
scarb test test_CU06

# Run specific test
scarb test test_claim_prize_success

# Run with detailed output
scarb test test_CU06 --verbose

📌 Additional Notes

Expected coverage:

• Successful cases: 30%
• Security validations: 40%
• Error cases: 30%
• Target: >90% code coverage on ClaimPrize function

Test priority:

1. High: Security tests (ownership, double claim, reentrancy)
2. Medium: Validation tests (draw state, assigned prizes)
3. Low: Integration and performance tests

Implementation notes:

• Use start_prank / stop_prank to simulate different callers
• Use declare to deploy contracts in test environment
• Mock vault if needed to simulate specific scenarios
• Consider tests with gas measurement for future optimization

Frontend testing (optional for separate issue):

• Tests with Vitest for UI components
• Integration tests with mock wallet
• E2E tests with Playwright (optional)

Documentation:

• Document each test with explanatory comments
• Add section in README about running tests
• Include examples of expected output

⚠️ Before Applying

Please read this guide: Contributor Guidelines

Definition of Done:

• File test_CU06_claim_prize.cairo created with all unit tests
• File test_CU06_integration.cairo created with integration tests
• All tests pass successfully with scarb test
• Code coverage >90% for ClaimPrize function
• Helpers and utilities implemented
• Test documentation added to README
• Reentrancy tests implemented and passing
• Event tests validating correct fields
• Balance tests validating correct transfers