build(fee): tx_context and create_tx_info cannot_fail (#538)

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crates/blockifier/src/blockifier/stateful_validator.rs

@@ -18,11 +18,7 @@ use crate::state::cached_state::CachedState;
 use crate::state::errors::StateError;
 use crate::state::state_api::StateReader;
 use crate::transaction::account_transaction::AccountTransaction;
-use crate::transaction::errors::{
-    TransactionExecutionError,
-    TransactionInfoCreationError,
-    TransactionPreValidationError,
-};
+use crate::transaction::errors::{TransactionExecutionError, TransactionPreValidationError};
 use crate::transaction::transaction_execution::Transaction;
 use crate::transaction::transactions::ValidatableTransaction;
 
@@ -40,8 +36,6 @@ pub enum StatefulValidatorError {
     TransactionExecutorError(#[from] TransactionExecutorError),
     #[error(transparent)]
     TransactionPreValidationError(#[from] TransactionPreValidationError),
-    #[error(transparent)]
-    TransactionCreationError(#[from] TransactionInfoCreationError),
 }
 
 pub type StatefulValidatorResult<T> = Result<T, StatefulValidatorError>;
@@ -71,7 +65,7 @@ impl<S: StateReader> StatefulValidator<S> {
             return Ok(());
         }
 
-        let tx_context = self.tx_executor.block_context.to_tx_context(&tx)?;
+        let tx_context = self.tx_executor.block_context.to_tx_context(&tx);
         self.perform_pre_validation_stage(&tx, &tx_context)?;
 
         if skip_validate {
@@ -118,7 +112,7 @@ impl<S: StateReader> StatefulValidator<S> {
         mut remaining_gas: u64,
     ) -> StatefulValidatorResult<(Option<CallInfo>, TransactionReceipt)> {
         let mut execution_resources = ExecutionResources::default();
-        let tx_context = Arc::new(self.tx_executor.block_context.to_tx_context(tx)?);
+        let tx_context = Arc::new(self.tx_executor.block_context.to_tx_context(tx));
 
         let limit_steps_by_resources = true;
         let validate_call_info = tx.validate_tx(

crates/blockifier/src/concurrency/versioned_state_test.rs

@@ -233,7 +233,7 @@ fn test_run_parallel_txs(max_resource_bounds: ValidResourceBounds) {
         &mut NonceManager::default(),
     );
     let account_tx_1 = AccountTransaction::DeployAccount(deploy_account_tx_1);
-    let enforce_fee = account_tx_1.create_tx_info().unwrap().enforce_fee();
+    let enforce_fee = account_tx_1.create_tx_info().enforce_fee();
 
     let class_hash = grindy_account.get_class_hash();
     let ctor_storage_arg = felt!(1_u8);
@@ -248,7 +248,7 @@ fn test_run_parallel_txs(max_resource_bounds: ValidResourceBounds) {
     let deploy_account_tx_2 = deploy_account_tx(deploy_tx_args, nonce_manager);
     let account_address = deploy_account_tx_2.contract_address();
     let account_tx_2 = AccountTransaction::DeployAccount(deploy_account_tx_2);
-    let tx_context = block_context.to_tx_context(&account_tx_2).unwrap();
+    let tx_context = block_context.to_tx_context(&account_tx_2);
     let fee_type = tx_context.tx_info.fee_type();
 
     let deployed_account_balance_key = get_fee_token_var_address(account_address);

crates/blockifier/src/concurrency/worker_logic.rs

@@ -230,10 +230,7 @@ impl<'a, S: StateReader> WorkerExecutor<'a, S> {
             &mut execution_output.as_mut().expect(EXECUTION_OUTPUTS_UNWRAP_ERROR).result;
 
         if let Ok(tx_execution_info) = tx_result.as_mut() {
-            let tx_context = self
-                .block_context
-                .to_tx_context(&self.chunk[tx_index])
-                .expect("Failed to create tx context.");
+            let tx_context = self.block_context.to_tx_context(&self.chunk[tx_index]);
             // Add the deleted sequencer balance key to the storage keys.
             let concurrency_mode = true;
             tx_state_changes_keys.update_sequencer_key_in_storage(

crates/blockifier/src/concurrency/worker_logic_test.rs

@@ -174,7 +174,7 @@ pub fn test_commit_tx() {
                 assert_eq!(felt!(expected_sequencer_storage_read), actual_sequencer_storage_read,);
             }
         }
-        let tx_context = executor.block_context.to_tx_context(&txs[commit_idx]).unwrap();
+        let tx_context = executor.block_context.to_tx_context(&txs[commit_idx]);
         expected_sequencer_balance_low += actual_fee;
         // Check that the sequencer balance was updated correctly in the state.
         verify_sequencer_balance_update(
@@ -228,7 +228,7 @@ fn test_commit_tx_when_sender_is_sequencer() {
     let read_values_before_commit = fee_transfer_call_info.storage_read_values.clone();
     drop(execution_task_outputs);
 
-    let tx_context = &executor.block_context.to_tx_context(&sequencer_tx[0]).unwrap();
+    let tx_context = &executor.block_context.to_tx_context(&sequencer_tx[0]);
     let fee_token_address =
         executor.block_context.chain_info.fee_token_address(&tx_context.tx_info.fee_type());
     let sequencer_balance_high_before =

crates/blockifier/src/context.rs

@@ -7,7 +7,6 @@ use starknet_api::core::{ChainId, ContractAddress};
 
 use crate::blockifier::block::BlockInfo;
 use crate::bouncer::BouncerConfig;
-use crate::transaction::errors::TransactionInfoCreationError;
 use crate::transaction::objects::{
     FeeType,
     HasRelatedFeeType,
@@ -63,15 +62,14 @@ impl BlockContext {
         &self.versioned_constants
     }
 
-    // TODO(Nimrod): Don't return `Result`.
     pub fn to_tx_context(
         &self,
         tx_info_creator: &impl TransactionInfoCreator,
-    ) -> Result<TransactionContext, TransactionInfoCreationError> {
-        Ok(TransactionContext {
+    ) -> TransactionContext {
+        TransactionContext {
             block_context: self.clone(),
-            tx_info: tx_info_creator.create_tx_info()?,
-        })
+            tx_info: tx_info_creator.create_tx_info(),
+        }
     }
 }
 

crates/blockifier/src/fee/fee_test.rs

@@ -162,7 +162,7 @@ fn test_discounted_gas_overdraft(
     let charge_fee = true;
     let report = PostExecutionReport::new(
         &mut state,
-        &block_context.to_tx_context(&tx).unwrap(),
+        &block_context.to_tx_context(&tx),
         &tx_receipt,
         charge_fee,
     )

crates/blockifier/src/fee/gas_usage_test.rs

@@ -205,9 +205,8 @@ fn test_get_message_segment_length(
 
 #[rstest]
 fn test_compute_discounted_gas_from_gas_vector() {
-    let tx_context = BlockContext::create_for_testing()
-        .to_tx_context(&account_invoke_tx(invoke_tx_args! {}))
-        .unwrap();
+    let tx_context =
+        BlockContext::create_for_testing().to_tx_context(&account_invoke_tx(invoke_tx_args! {}));
     let gas_usage = GasVector { l1_gas: 100, l1_data_gas: 2, ..Default::default() };
     let actual_result = compute_discounted_gas_from_gas_vector(&gas_usage, &tx_context);
 

crates/blockifier/src/test_utils/prices.rs

@@ -72,11 +72,7 @@ fn fee_transfer_resources(
             state,
             &mut ExecutionResources::default(),
             &mut EntryPointExecutionContext::new(
-                Arc::new(
-                    block_context
-                        .to_tx_context(&account_invoke_tx(InvokeTxArgs::default()))
-                        .unwrap(),
-                ),
+                Arc::new(block_context.to_tx_context(&account_invoke_tx(InvokeTxArgs::default()))),
                 ExecutionMode::Execute,
                 false,
             ),

crates/blockifier/src/transaction/account_transaction.rs

@@ -33,7 +33,6 @@ use crate::transaction::constants;
 use crate::transaction::errors::{
     TransactionExecutionError,
     TransactionFeeError,
-    TransactionInfoCreationError,
     TransactionPreValidationError,
 };
 use crate::transaction::objects::{
@@ -681,7 +680,7 @@ impl<U: UpdatableState> ExecutableTransaction<U> for AccountTransaction {
         block_context: &BlockContext,
         execution_flags: ExecutionFlags,
     ) -> TransactionExecutionResult<TransactionExecutionInfo> {
-        let tx_context = Arc::new(block_context.to_tx_context(self)?);
+        let tx_context = Arc::new(block_context.to_tx_context(self));
         self.verify_tx_version(tx_context.tx_info.version())?;
 
         // Nonce and fee check should be done before running user code.
@@ -738,8 +737,7 @@ impl<U: UpdatableState> ExecutableTransaction<U> for AccountTransaction {
 }
 
 impl TransactionInfoCreator for AccountTransaction {
-    // TODO(Nimrod): This function should return `TransactionInfo` without a result.
-    fn create_tx_info(&self) -> Result<TransactionInfo, TransactionInfoCreationError> {
+    fn create_tx_info(&self) -> TransactionInfo {
         match self {
             Self::Declare(tx) => tx.create_tx_info(),
             Self::DeployAccount(tx) => tx.create_tx_info(),

crates/blockifier/src/transaction/account_transactions_test.rs

@@ -171,7 +171,7 @@ fn test_fee_enforcement(
     );
 
     let account_tx = AccountTransaction::DeployAccount(deploy_account_tx);
-    let enforce_fee = account_tx.create_tx_info().unwrap().enforce_fee();
+    let enforce_fee = account_tx.create_tx_info().enforce_fee();
     let result = account_tx.execute(state, &block_context, true, true);
     assert_eq!(result.is_err(), enforce_fee);
 }
@@ -652,7 +652,7 @@ fn test_fail_declare(block_context: BlockContext, max_fee: Fee) {
     );
 
     // Fail execution, assert nonce and balance are unchanged.
-    let tx_info = declare_account_tx.create_tx_info().unwrap();
+    let tx_info = declare_account_tx.create_tx_info();
     let initial_balance = state
         .get_fee_token_balance(account_address, chain_info.fee_token_address(&tx_info.fee_type()))
         .unwrap();
@@ -931,7 +931,7 @@ fn test_max_fee_to_max_steps_conversion(
         resource_bounds: l1_resource_bounds(actual_gas_used, actual_strk_gas_price.into()),
         nonce: nonce_manager.next(account_address),
     });
-    let tx_context1 = Arc::new(block_context.to_tx_context(&account_tx1).unwrap());
+    let tx_context1 = Arc::new(block_context.to_tx_context(&account_tx1));
     let execution_context1 = EntryPointExecutionContext::new_invoke(tx_context1, true);
     let max_steps_limit1 = execution_context1.vm_run_resources.get_n_steps();
     let tx_execution_info1 = account_tx1.execute(&mut state, &block_context, true, true).unwrap();
@@ -951,7 +951,7 @@ fn test_max_fee_to_max_steps_conversion(
         resource_bounds: l1_resource_bounds(2 * actual_gas_used, actual_strk_gas_price.into()),
         nonce: nonce_manager.next(account_address),
     });
-    let tx_context2 = Arc::new(block_context.to_tx_context(&account_tx2).unwrap());
+    let tx_context2 = Arc::new(block_context.to_tx_context(&account_tx2));
     let execution_context2 = EntryPointExecutionContext::new_invoke(tx_context2, true);
     let max_steps_limit2 = execution_context2.vm_run_resources.get_n_steps();
     let tx_execution_info2 = account_tx2.execute(&mut state, &block_context, true, true).unwrap();

crates/blockifier/src/transaction/errors.rs

@@ -112,8 +112,6 @@ pub enum TransactionExecutionError {
     InvalidSegmentStructure(usize, usize),
     #[error(transparent)]
     ProgramError(#[from] ProgramError),
-    #[error(transparent)]
-    TransactionInfoCreationError(#[from] TransactionInfoCreationError),
 }
 
 #[derive(Debug, Error)]
@@ -140,12 +138,3 @@ pub enum NumericConversionError {
     #[error("Conversion of {0} to u128 unsuccessful.")]
     U128ToUsizeError(u128),
 }
-
-// TODO(Nimrod): Delete this error once `create_tx_info` stops returning a `Result`.
-#[derive(Debug, Error)]
-pub enum TransactionInfoCreationError {
-    #[error("Invalid ResourceMapping combination was given: {0}")]
-    InvalidResourceMapping(String),
-    #[error(transparent)]
-    StarknetAPIError(#[from] StarknetApiError),
-}

crates/blockifier/src/transaction/objects.rs

@@ -38,7 +38,6 @@ use crate::transaction::constants;
 use crate::transaction::errors::{
     TransactionExecutionError,
     TransactionFeeError,
-    TransactionInfoCreationError,
     TransactionPreValidationError,
 };
 use crate::utils::{u128_from_usize, usize_from_u128};
@@ -570,5 +569,5 @@ pub enum FeeType {
 }
 
 pub trait TransactionInfoCreator {
-    fn create_tx_info(&self) -> Result<TransactionInfo, TransactionInfoCreationError>;
+    fn create_tx_info(&self) -> TransactionInfo;
 }

crates/blockifier/src/transaction/post_execution_test.rs

@@ -112,7 +112,7 @@ fn test_revert_on_overdraft(
         resource_bounds: max_resource_bounds.clone(),
         nonce: nonce_manager.next(account_address),
     });
-    let tx_info = approve_tx.create_tx_info().unwrap();
+    let tx_info = approve_tx.create_tx_info();
     let approval_execution_info =
         approve_tx.execute(&mut state, &block_context, true, true).unwrap();
     assert!(!approval_execution_info.is_reverted());

crates/blockifier/src/transaction/transaction_execution.rs

@@ -12,7 +12,7 @@ use crate::fee::actual_cost::TransactionReceipt;
 use crate::state::cached_state::TransactionalState;
 use crate::state::state_api::UpdatableState;
 use crate::transaction::account_transaction::AccountTransaction;
-use crate::transaction::errors::{TransactionFeeError, TransactionInfoCreationError};
+use crate::transaction::errors::TransactionFeeError;
 use crate::transaction::objects::{
     TransactionExecutionInfo,
     TransactionExecutionResult,
@@ -100,7 +100,7 @@ impl Transaction {
 }
 
 impl TransactionInfoCreator for Transaction {
-    fn create_tx_info(&self) -> Result<TransactionInfo, TransactionInfoCreationError> {
+    fn create_tx_info(&self) -> TransactionInfo {
         match self {
             Self::AccountTransaction(account_tx) => account_tx.create_tx_info(),
             Self::L1HandlerTransaction(l1_handler_tx) => l1_handler_tx.create_tx_info(),
@@ -115,7 +115,7 @@ impl<U: UpdatableState> ExecutableTransaction<U> for L1HandlerTransaction {
         block_context: &BlockContext,
         _execution_flags: ExecutionFlags,
     ) -> TransactionExecutionResult<TransactionExecutionInfo> {
-        let tx_context = Arc::new(block_context.to_tx_context(self)?);
+        let tx_context = Arc::new(block_context.to_tx_context(self));
 
         let mut execution_resources = ExecutionResources::default();
         let mut context = EntryPointExecutionContext::new_invoke(tx_context.clone(), true);
@@ -184,7 +184,7 @@ impl<U: UpdatableState> ExecutableTransaction<U> for Transaction {
         let tx_execution_summary = tx_execution_info.summarize();
         let mut tx_state_changes_keys = state.get_actual_state_changes()?.into_keys();
         tx_state_changes_keys.update_sequencer_key_in_storage(
-            &block_context.to_tx_context(self)?,
+            &block_context.to_tx_context(self),
             &tx_execution_info,
             concurrency_mode,
         );