Smart Contract Vault Deposit & Test Suite

[memplethee-lab]

• closes Issue 2.1: Implement Vault Deposit Function #5

Overview

Implements secure USDC vault deposit functionality with cryptographic authorization, persistent balance tracking, and comprehensive test coverage for Smasage's Soroban smart contract.

Issues Addressed

1. Vault Deposit Function

• Secure Deposits: Cryptographic authorization via from.require_auth()
• Token Transfer: USDC transferred to vault via Soroban TokenClient interface
• Individual Tracking: User-specific balance persistence in DataKey::UserBalance
• Protocol Tracking: World-state total vault deposits in DataKey::TotalVaultDeposits
• Validation: Rejects zero/negative amounts with clear error messages
• Backward Compatible: Legacy deposit() function refactored to use vault_deposit internally

Implementation:

pub fn vault_deposit(env: Env, from: Address, amount: i128) {
    from.require_auth();  // ✅ Authorization
    assert!(amount > 0, "Deposit amount must be greater than 0");
    
    Self::transfer_usdc_from_user(&env, &from, amount);  // ✅ Token transfer
    
    // ✅ Individual balance tracking
    let mut user_balance = env.storage().persistent()
        .get(&DataKey::UserBalance(from.clone())).unwrap_or(0);
    user_balance += amount;
    env.storage().persistent().set(&DataKey::UserBalance(from.clone()), &user_balance);
    
    // ✅ Protocol-wide total tracking
    let mut total_deposits = env.storage().persistent()
        .get(&DataKey::TotalVaultDeposits).unwrap_or(0);
    total_deposits += amount;
    env.storage().persistent().set(&DataKey::TotalVaultDeposits, &total_deposits);
}

2. Vault Balance Getters

• get_vault_balance(user) - Retrieves user's current vault balance
• get_total_vault_deposits() - Retrieves protocol-wide total

3. Comprehensive Test Suite

• 5 dedicated tests covering all acceptance criteria
• Multiple user scenarios validating independent balance tracking
• Error handling for invalid deposit amounts
• Accumulation testing for repeated deposits

Test Coverage:

• test_vault_deposit_success - Basic single user deposit
• test_vault_deposit_multiple_users - Multi-user balance isolation
• test_vault_deposit_accumulation - Repeated deposits accumulate correctly
• test_vault_deposit_zero_amount - Panic on zero amount
• test_vault_deposit_negative_amount - Panic on negative amount

Files Modified:

• contracts/src/lib.rs - Added vault_deposit(), getters, and 5 tests (251 insertions)

Acceptance Criteria ✅

• vault_deposit(from, amount) function implemented
• Cryptographic authorization enforced via require_auth()
• USDC transferred to vault contract
• User balance tracked persistently per address
• Protocol-wide total tracked in TotalVaultDeposits
• Invalid amounts rejected with clear messages
• Multiple users' balances tracked independently
• Repeated deposits accumulate correctly
• Getter functions return accurate balances
• Test suite covers all scenarios (5 tests, 100% criteria coverage)
• Backward compatibility maintained (legacy deposit() refactored)

Testing

Build and run tests:

cd contracts
cargo test --lib

Run only vault deposit tests:

cargo test --lib test_vault_deposit

Code Summary

DataKey Updates

pub enum DataKey {
    UserBalance(Address),           // Individual user vault balance
    TotalVaultDeposits,             // Protocol-wide total
    UserBlendBalance(Address),      // ... existing keys
    UserLPShares(Address),
    UserGoldBalance(Address),
    BlendPoolAddress,
    USDCTokenAddress,
    BlendPosition(Address),
}

Function Signatures

pub fn vault_deposit(env: Env, from: Address, amount: i128) → ()
pub fn get_vault_balance(env: Env, user: Address) → i128
pub fn get_total_vault_deposits(env: Env) → i128

Next Steps

1. Integration: Connect vault_deposit() to frontend deposit UI
2. Withdrawal: Implement paired vault_withdraw() function
3. Yield Routing: Route deposits to Blend/Soroswap/Gold protocols
4. Contract Deployment: Compile to WebAssembly and deploy to Stellar testnet

Technical Notes

• All tests use Soroban SDK's Env::default() with mock auth
• MockToken and MockBlendPool contracts provide test infrastructure
• Individual and total balance tracking ensures dual audit trail
• Error messages follow Soroban assertion pattern conventions
• 60% Blend / 30% LP / 10% Gold allocation pattern integrated

Build Status

✅ Compiles successfully (0 errors)
✅ All tests pass (5/5 vault deposit tests + existing integration tests)
✅ Ready for deployment to Stellar testnet

---

• Closes Issue 4.3: Refine Chat UI Animations #13

[drips-wave]

@memplethee-lab Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits

[soomtochukwu]

@memplethee-lab, could you look into this?

[memplethee-lab]

@approved workflow

[memplethee-lab]

@soomtochukwu