refactor(fee): block context creator may fail (#507)

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crates/blockifier/src/blockifier/stateful_validator.rs

@@ -71,7 +71,7 @@ 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 +118,7 @@ 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

@@ -248,7 +248,7 @@ fn test_run_parallel_txs(max_resource_bounds: DeprecatedResourceBoundsMapping) {
     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);
+    let tx_context = block_context.to_tx_context(&account_tx_2).unwrap();
     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

@@ -230,7 +230,10 @@ 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]);
+            let tx_context = self
+                .block_context
+                .to_tx_context(&self.chunk[tx_index])
+                .expect("Failed to create tx context.");
             // 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]);
+        let tx_context = executor.block_context.to_tx_context(&txs[commit_idx]).unwrap();
         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]);
+    let tx_context = &executor.block_context.to_tx_context(&sequencer_tx[0]).unwrap();
     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

@@ -7,6 +7,7 @@ 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,
@@ -62,14 +63,15 @@ impl BlockContext {
         &self.versioned_constants
     }
 
+    // TODO(Nimrod): Don't return `Result`.
     pub fn to_tx_context(
         &self,
         tx_info_creator: &impl TransactionInfoCreator,
-    ) -> TransactionContext {
-        TransactionContext {
+    ) -> Result<TransactionContext, TransactionInfoCreationError> {
+        Ok(TransactionContext {
             block_context: self.clone(),
-            tx_info: tx_info_creator.create_tx_info().expect("todo"),
-        }
+            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),
+        &block_context.to_tx_context(&tx).unwrap(),
         &tx_receipt,
         charge_fee,
     )

crates/blockifier/src/fee/gas_usage_test.rs

@@ -205,8 +205,9 @@ 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! {}));
+    let tx_context = BlockContext::create_for_testing()
+        .to_tx_context(&account_invoke_tx(invoke_tx_args! {}))
+        .unwrap();
     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

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

crates/blockifier/src/transaction/account_transaction.rs

@@ -681,7 +681,7 @@ 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.

crates/blockifier/src/transaction/account_transactions_test.rs

@@ -932,7 +932,7 @@ 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));
+    let tx_context1 = Arc::new(block_context.to_tx_context(&account_tx1).unwrap());
     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();
@@ -952,7 +952,7 @@ 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));
+    let tx_context2 = Arc::new(block_context.to_tx_context(&account_tx2).unwrap());
     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

@@ -112,6 +112,8 @@ pub enum TransactionExecutionError {
     InvalidSegmentStructure(usize, usize),
     #[error(transparent)]
     ProgramError(#[from] ProgramError),
+    #[error(transparent)]
+    TransactionInfoCreationError(#[from] TransactionInfoCreationError),
 }
 
 #[derive(Debug, Error)]

crates/blockifier/src/transaction/transaction_execution.rs

@@ -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,
         );

crates/blockifier/src/transaction/transactions_test.rs

@@ -422,7 +422,7 @@ fn test_invoke_tx(
     let sender_address = invoke_tx.sender_address();
 
     let account_tx = AccountTransaction::Invoke(invoke_tx);
-    let tx_context = block_context.to_tx_context(&account_tx);
+    let tx_context = block_context.to_tx_context(&account_tx).unwrap();
 
     let actual_execution_info = account_tx.execute(state, block_context, true, true).unwrap();
 
@@ -792,7 +792,7 @@ fn assert_failure_if_resource_bounds_exceed_balance(
     block_context: &BlockContext,
     invalid_tx: AccountTransaction,
 ) {
-    match block_context.to_tx_context(&invalid_tx).tx_info {
+    match block_context.to_tx_context(&invalid_tx).unwrap().tx_info {
         TransactionInfo::Deprecated(context) => {
             assert_matches!(
                 invalid_tx.execute(state, block_context, true, true).unwrap_err(),
@@ -1040,7 +1040,7 @@ fn test_invalid_nonce(
     let invalid_nonce = nonce!(1_u8);
     let invalid_tx =
         account_invoke_tx(invoke_tx_args! { nonce: invalid_nonce, ..valid_invoke_tx_args.clone() });
-    let invalid_tx_context = block_context.to_tx_context(&invalid_tx);
+    let invalid_tx_context = block_context.to_tx_context(&invalid_tx).unwrap();
     let pre_validation_err = invalid_tx
         .perform_pre_validation_stage(&mut transactional_state, &invalid_tx_context, false, true)
         .unwrap_err();
@@ -1060,7 +1060,7 @@ fn test_invalid_nonce(
     let valid_tx =
         account_invoke_tx(invoke_tx_args! { nonce: valid_nonce, ..valid_invoke_tx_args.clone() });
 
-    let valid_tx_context = block_context.to_tx_context(&valid_tx);
+    let valid_tx_context = block_context.to_tx_context(&valid_tx).unwrap();
     valid_tx
         .perform_pre_validation_stage(&mut transactional_state, &valid_tx_context, false, false)
         .unwrap();
@@ -1069,7 +1069,7 @@ fn test_invalid_nonce(
     let invalid_nonce = nonce!(0_u8);
     let invalid_tx =
         account_invoke_tx(invoke_tx_args! { nonce: invalid_nonce, ..valid_invoke_tx_args.clone() });
-    let invalid_tx_context = block_context.to_tx_context(&invalid_tx);
+    let invalid_tx_context = block_context.to_tx_context(&invalid_tx).unwrap();
     let pre_validation_err = invalid_tx
         .perform_pre_validation_stage(&mut transactional_state, &invalid_tx_context, false, false)
         .unwrap_err();
@@ -1185,7 +1185,7 @@ fn test_declare_tx(
         undeclared_class_hash == class_hash
     );
     let fee_type = &account_tx.fee_type();
-    let tx_context = &block_context.to_tx_context(&account_tx);
+    let tx_context = &block_context.to_tx_context(&account_tx).unwrap();
     let actual_execution_info = account_tx.execute(state, block_context, true, true).unwrap();
 
     // Build expected validate call info.
@@ -1328,7 +1328,7 @@ fn test_deploy_account_tx(
 
     let account_tx = AccountTransaction::DeployAccount(deploy_account);
     let fee_type = &account_tx.fee_type();
-    let tx_context = &block_context.to_tx_context(&account_tx);
+    let tx_context = &block_context.to_tx_context(&account_tx).unwrap();
     let actual_execution_info = account_tx.execute(state, block_context, true, true).unwrap();
 
     // Build expected validate call info.
@@ -1470,7 +1470,7 @@ fn test_fail_deploy_account_undeclared_class_hash(
         deploy_account_tx_args! {resource_bounds: max_resource_bounds,  class_hash: undeclared_hash },
         &mut nonce_manager,
     );
-    let tx_context = block_context.to_tx_context(&deploy_account);
+    let tx_context = block_context.to_tx_context(&deploy_account).unwrap();
     let fee_type = tx_context.tx_info.fee_type();
 
     // Fund account, so as not to fail pre-validation.