feat: Use timestamp of last block when dry running transactions (#2206)

## Description
Closes #2128 

This PR adds the option to specify a timestamp in
BlockProducer::dry_run. When no timestamp is provided, the block
producer will use the time stamp of the previous block, instead of using
`Tai64::now()` (previous behavior).

## Checklist
- [x] Breaking changes are clearly marked as such in the PR description
and changelog
- [x] New behavior is reflected in tests

### Before requesting review
- [x] I have reviewed the code myself
- [x] I have created follow-up issues caused by this PR and linked them
here

### After merging, notify other teams

- [ ] [Rust SDK](https://github.com/FuelLabs/fuels-rs/)

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Changed
 
 #### Breaking
+- [2206](https://github.com/FuelLabs/fuel-core/pull/2206): Use timestamp of last block when dry running transactions.
 - [2153](https://github.com/FuelLabs/fuel-core/pull/2153): Updated default gas costs for the local testnet configuration to match `fuel-core 0.35.0`.
 
 ## [Version 0.36.0]

crates/fuel-core/src/graphql_api/ports.rs

@@ -209,6 +209,7 @@ pub trait BlockProducerPort: Send + Sync {
         &self,
         transactions: Vec<Transaction>,
         height: Option<BlockHeight>,
+        time: Option<Tai64>,
         utxo_validation: Option<bool>,
         gas_price: Option<u64>,
     ) -> anyhow::Result<Vec<TransactionExecutionStatus>>;

crates/fuel-core/src/schema/tx.rs

@@ -299,7 +299,8 @@ impl TxMutation {
         let tx_statuses = block_producer
             .dry_run_txs(
                 transactions,
-                None,
+                None, // TODO(#1749): Pass parameter from API
+                None, // TODO(#1749): Pass parameter from API
                 utxo_validation,
                 gas_price.map(|x| x.into()),
             )

crates/fuel-core/src/service/adapters/graphql_api.rs

@@ -106,11 +106,12 @@ impl BlockProducerPort for BlockProducerAdapter {
         &self,
         transactions: Vec<Transaction>,
         height: Option<BlockHeight>,
+        time: Option<Tai64>,
         utxo_validation: Option<bool>,
         gas_price: Option<u64>,
     ) -> anyhow::Result<Vec<TransactionExecutionStatus>> {
         self.block_producer
-            .dry_run(transactions, height, utxo_validation, gas_price)
+            .dry_run(transactions, height, time, utxo_validation, gas_price)
             .await
     }
 }

crates/services/producer/src/block_producer.rs

@@ -183,7 +183,9 @@ where
 
         let source = tx_source(height);
 
-        let header = self.new_header(height, block_time).await?;
+        let header = self
+            .new_header_with_new_da_height(height, block_time)
+            .await?;
 
         let gas_price = self.calculate_gas_price().await?;
 
@@ -268,26 +270,33 @@ where
     GasPriceProvider: GasPriceProviderConstraint,
     ConsensusProvider: ConsensusParametersProvider,
 {
-    // TODO: Support custom `block_time` for `dry_run`.
     /// Simulates multiple transactions without altering any state. Does not acquire the production lock.
     /// since it is basically a "read only" operation and shouldn't get in the way of normal
     /// production.
     pub async fn dry_run(
         &self,
         transactions: Vec<Transaction>,
         height: Option<BlockHeight>,
+        time: Option<Tai64>,
         utxo_validation: Option<bool>,
         gas_price: Option<u64>,
     ) -> anyhow::Result<Vec<TransactionExecutionStatus>> {
         let view = self.view_provider.latest_view()?;
-        let height = height.unwrap_or_else(|| {
-            view.latest_height()
-                .unwrap_or_default()
+        let latest_height = view.latest_height().unwrap_or_default();
+
+        let simulated_height = height.unwrap_or_else(|| {
+            latest_height
                 .succ()
                 .expect("It is impossible to overflow the current block height")
         });
 
-        let header = self._new_header(height, Tai64::now())?;
+        let simulated_time = time.unwrap_or_else(|| {
+            view.get_block(&latest_height)
+                .map(|block| block.header().time())
+                .unwrap_or(Tai64::UNIX_EPOCH)
+        });
+
+        let header = self.new_header(simulated_height, simulated_time)?;
 
         let gas_price = if let Some(inner) = gas_price {
             inner
@@ -341,12 +350,12 @@ where
     ConsensusProvider: ConsensusParametersProvider,
 {
     /// Create the header for a new block at the provided height
-    async fn new_header(
+    async fn new_header_with_new_da_height(
         &self,
         height: BlockHeight,
         block_time: Tai64,
     ) -> anyhow::Result<PartialBlockHeader> {
-        let mut block_header = self._new_header(height, block_time)?;
+        let mut block_header = self.new_header(height, block_time)?;
         let previous_da_height = block_header.da_height;
         let gas_limit = self
             .consensus_parameters_provider
@@ -367,7 +376,7 @@ where
         block_time: Tai64,
         da_height: DaBlockHeight,
     ) -> anyhow::Result<PartialBlockHeader> {
-        let mut block_header = self._new_header(height, block_time)?;
+        let mut block_header = self.new_header(height, block_time)?;
         block_header.application.da_height = da_height;
         Ok(block_header)
     }
@@ -414,7 +423,7 @@ where
         }
     }
 
-    fn _new_header(
+    fn new_header(
         &self,
         height: BlockHeight,
         block_time: Tai64,

crates/services/producer/src/block_producer/tests.rs

@@ -543,6 +543,104 @@ mod produce_and_execute_block_txpool {
     }
 }
 
+// Tests for the `dry_run` method.
+mod dry_run {
+    use super::*;
+
+    #[tokio::test]
+    async fn dry_run__executes_with_given_timestamp() {
+        // Given
+        let simulated_block_time = Tai64::from_unix(1337);
+        let executor = MockExecutorWithCapture::default();
+        let ctx = TestContext::default_from_executor(executor.clone());
+
+        // When
+        let _ = ctx
+            .producer()
+            .dry_run(vec![], None, Some(simulated_block_time), None, None)
+            .await;
+
+        // Then
+        assert_eq!(executor.captured_block_timestamp(), simulated_block_time);
+    }
+
+    #[tokio::test]
+    async fn dry_run__executes_with_past_timestamp() {
+        // Given
+        let simulated_block_time = Tai64::UNIX_EPOCH;
+        let last_block_time = Tai64::from_unix(1337);
+
+        let executor = MockExecutorWithCapture::default();
+        let ctx = TestContextBuilder::new()
+            .with_prev_time(last_block_time)
+            .build_with_executor(executor.clone());
+
+        // When
+        let _ = ctx
+            .producer()
+            .dry_run(vec![], None, Some(simulated_block_time), None, None)
+            .await;
+
+        // Then
+        assert_eq!(executor.captured_block_timestamp(), simulated_block_time);
+    }
+
+    #[tokio::test]
+    async fn dry_run__uses_last_block_timestamp_when_no_time_provided() {
+        // Given
+        let last_block_time = Tai64::from_unix(1337);
+
+        let executor = MockExecutorWithCapture::default();
+        let ctx = TestContextBuilder::new()
+            .with_prev_time(last_block_time)
+            .build_with_executor(executor.clone());
+
+        // When
+        let _ = ctx.producer().dry_run(vec![], None, None, None, None).await;
+
+        // Then
+        assert_eq!(executor.captured_block_timestamp(), last_block_time);
+    }
+
+    #[tokio::test]
+    async fn dry_run__errors_early_if_height_is_lower_than_chain_tip() {
+        // Given
+        let last_block_height = BlockHeight::new(42);
+
+        let executor = MockExecutorWithCapture::default();
+        let ctx = TestContextBuilder::new()
+            .with_prev_height(last_block_height)
+            .build_with_executor(executor.clone());
+
+        // When
+        let _ = ctx
+            .producer()
+            .dry_run(vec![], last_block_height.pred(), None, None, None)
+            .await
+            .expect_err("expected failure");
+
+        // Then
+        assert!(executor.has_no_captured_block_timestamp());
+    }
+
+    impl MockExecutorWithCapture<Transaction> {
+        fn captured_block_timestamp(&self) -> Tai64 {
+            *self
+                .captured
+                .lock()
+                .unwrap()
+                .as_ref()
+                .expect("should have captured a block")
+                .header_to_produce
+                .time()
+        }
+
+        fn has_no_captured_block_timestamp(&self) -> bool {
+            self.captured.lock().unwrap().is_none()
+        }
+    }
+}
+
 use fuel_core_types::fuel_tx::field::MintGasPrice;
 use proptest::{
     prop_compose,
@@ -804,6 +902,7 @@ struct TestContextBuilder {
     prev_da_height: DaBlockHeight,
     block_gas_limit: Option<u64>,
     prev_height: BlockHeight,
+    prev_time: Tai64,
 }
 
 impl TestContextBuilder {
@@ -814,6 +913,7 @@ impl TestContextBuilder {
             prev_da_height: 1u64.into(),
             block_gas_limit: None,
             prev_height: 0u32.into(),
+            prev_time: Tai64::UNIX_EPOCH,
         }
     }
 
@@ -846,16 +946,25 @@ impl TestContextBuilder {
         self
     }
 
-    fn build(&self) -> TestContext<MockExecutor> {
+    fn with_prev_time(mut self, prev_time: Tai64) -> Self {
+        self.prev_time = prev_time;
+        self
+    }
+
+    fn pre_existing_blocks(&self) -> Arc<Mutex<HashMap<BlockHeight, CompressedBlock>>> {
         let da_height = self.prev_da_height;
-        let previous_block = PartialFuelBlock {
+        let height = self.prev_height;
+        let time = self.prev_time;
+
+        let block = PartialFuelBlock {
             header: PartialBlockHeader {
                 application: ApplicationHeader {
                     da_height,
                     ..Default::default()
                 },
                 consensus: ConsensusHeader {
-                    height: self.prev_height,
+                    height,
+                    time,
                     ..Default::default()
                 },
             },
@@ -865,67 +974,49 @@ impl TestContextBuilder {
         .unwrap()
         .compress(&Default::default());
 
-        let db = MockDb {
-            blocks: Arc::new(Mutex::new(
-                vec![(self.prev_height, previous_block)]
-                    .into_iter()
-                    .collect(),
-            )),
-            consensus_parameters_version: 0,
-            state_transition_bytecode_version: 0,
-        };
+        Arc::new(Mutex::new(HashMap::from_iter(Some((height, block)))))
+    }
+
+    fn build(self) -> TestContext<MockExecutor> {
+        let block_gas_limit = self.block_gas_limit.unwrap_or_default();
 
         let mock_relayer = MockRelayer {
             latest_block_height: self.latest_block_height,
             latest_da_blocks_with_costs: self.blocks_with_gas_costs.clone(),
             ..Default::default()
         };
 
+        let db = MockDb {
+            blocks: self.pre_existing_blocks(),
+            consensus_parameters_version: 0,
+            state_transition_bytecode_version: 0,
+        };
+
         TestContext {
             relayer: mock_relayer,
-            block_gas_limit: self.block_gas_limit.unwrap_or_default(),
+            block_gas_limit,
             ..TestContext::default_from_db(db)
         }
     }
 
-    fn build_with_executor<Ex>(&self, executor: Ex) -> TestContext<Ex> {
-        let da_height = self.prev_da_height;
-        let previous_block = PartialFuelBlock {
-            header: PartialBlockHeader {
-                application: ApplicationHeader {
-                    da_height,
-                    ..Default::default()
-                },
-                consensus: ConsensusHeader {
-                    height: self.prev_height,
-                    ..Default::default()
-                },
-            },
-            transactions: vec![],
-        }
-        .generate(&[], Default::default())
-        .unwrap()
-        .compress(&Default::default());
-
-        let db = MockDb {
-            blocks: Arc::new(Mutex::new(
-                vec![(self.prev_height, previous_block)]
-                    .into_iter()
-                    .collect(),
-            )),
-            consensus_parameters_version: 0,
-            state_transition_bytecode_version: 0,
-        };
+    fn build_with_executor<Ex>(self, executor: Ex) -> TestContext<Ex> {
+        let block_gas_limit = self.block_gas_limit.unwrap_or_default();
 
         let mock_relayer = MockRelayer {
             latest_block_height: self.latest_block_height,
             latest_da_blocks_with_costs: self.blocks_with_gas_costs.clone(),
             ..Default::default()
         };
 
+        let db = MockDb {
+            blocks: self.pre_existing_blocks(),
+            consensus_parameters_version: 0,
+            state_transition_bytecode_version: 0,
+        };
+
         TestContext {
             relayer: mock_relayer,
-            block_gas_limit: self.block_gas_limit.unwrap_or_default(),
+            block_gas_limit,
             ..TestContext::default_from_db_and_executor(db, executor)
         }
     }

crates/services/producer/src/mocks.rs

@@ -1,6 +1,7 @@
 use crate::ports::{
     BlockProducer,
     BlockProducerDatabase,
+    DryRunner,
     Relayer,
     TxPool,
 };
@@ -37,6 +38,7 @@ use fuel_core_types::{
             Error as ExecutorError,
             ExecutionResult,
             Result as ExecutorResult,
+            TransactionExecutionStatus,
             UncommittedResult,
         },
         txpool::ArcPoolTx,
@@ -227,6 +229,18 @@ impl BlockProducer<Vec<Transaction>> for MockExecutorWithCapture<Transaction> {
     }
 }
 
+impl DryRunner for MockExecutorWithCapture<Transaction> {
+    fn dry_run(
+        &self,
+        block: Components<Vec<Transaction>>,
+        _utxo_validation: Option<bool>,
+    ) -> ExecutorResult<Vec<TransactionExecutionStatus>> {
+        *self.captured.lock().unwrap() = Some(block);
+
+        Ok(Vec::new())
+    }
+}
+
 impl<Tx> Default for MockExecutorWithCapture<Tx> {
     fn default() -> Self {
         Self {