Implement remaining GraphQL operations for transactions. Resolves #68

src/server/RobinTTY.PersonalFinanceDashboard.API/Resolvers/Mutations/TransactionMutationResolvers.cs

@@ -22,6 +22,17 @@ public async Task<Transaction> CreateTransaction(TransactionRepository repositor
         return transaction;
     }
 
+    /// <summary>
+    /// Update an existing transaction.
+    /// </summary>
+    /// <param name="repository">The injected repository to use for data retrieval.</param>
+    /// <param name="transaction">The transaction to update.</param>
+    public async Task<Transaction> UpdateTransaction(TransactionRepository repository,
+        Transaction transaction)
+    {
+        return await repository.UpdateTransaction(transaction);
+    }
+
     /// <summary>
     /// Delete an existing transaction.
     /// </summary>

src/server/RobinTTY.PersonalFinanceDashboard.Infrastructure/Repositories/TransactionRepository.cs

@@ -77,14 +77,15 @@ public async Task<Transaction> AddTransaction(Transaction transaction)
     /// <summary>
     /// Updates an existing <see cref="Transaction"/>.
     /// </summary>
-    /// <param name="transactionDto">The <see cref="Transaction"/> to update.</param>
+    /// <param name="transaction">The <see cref="Transaction"/> to update.</param>
     /// <returns>The updated <see cref="Transaction"/>.</returns>
-    /// TODO: return Transaction not TransactionEntity
-    public async Task<TransactionEntity> UpdateTransaction(TransactionEntity transactionDto)
+    public async Task<Transaction> UpdateTransaction(Transaction transaction)
     {
-        var updateEntry = _dbContext.Transactions.Update(transactionDto);
+        var transactionEntity = _transactionMapper.ModelToEntity(transaction);
+        var updateEntry = _dbContext.Transactions.Update(transactionEntity);
         await _dbContext.SaveChangesAsync();
-        return updateEntry.Entity;
+
+        return _transactionMapper.EntityToModel(updateEntry.Entity);
     }
 
     /// <summary>