From 4c0a5bd19fb23d8ed8cc052fb8a3a7d2b5e8d78e Mon Sep 17 00:00:00 2001
From: Pearson White <pearson.white@nethermind.io>
Date: Wed, 23 Oct 2024 12:36:38 -0400
Subject: [PATCH] feat(blockifier): add library_call cairo native syscall

---
 .../src/execution/native/syscall_handler.rs   | 43 +++++++++++++++----
 .../syscalls/syscall_tests/library_call.rs    | 16 +++++--
 2 files changed, 46 insertions(+), 13 deletions(-)

diff --git a/crates/blockifier/src/execution/native/syscall_handler.rs b/crates/blockifier/src/execution/native/syscall_handler.rs
index cabaa3220f..f5e8c7f0ea 100644
--- a/crates/blockifier/src/execution/native/syscall_handler.rs
+++ b/crates/blockifier/src/execution/native/syscall_handler.rs
@@ -1,5 +1,6 @@
 use std::collections::HashSet;
 use std::hash::RandomState;
+use std::sync::Arc;
 
 use cairo_native::starknet::{
     ExecutionInfo,
@@ -11,12 +12,14 @@ use cairo_native::starknet::{
     U256,
 };
 use cairo_vm::vm::runners::cairo_runner::ExecutionResources;
-use starknet_api::core::{ContractAddress, EntryPointSelector};
+use starknet_api::contract_class::EntryPointType;
+use starknet_api::core::{ClassHash, ContractAddress, EntryPointSelector};
 use starknet_api::state::StorageKey;
+use starknet_api::transaction::Calldata;
 use starknet_types_core::felt::Felt;
 
 use crate::execution::call_info::{CallInfo, OrderedEvent, OrderedL2ToL1Message, Retdata};
-use crate::execution::entry_point::{CallEntryPoint, EntryPointExecutionContext};
+use crate::execution::entry_point::{CallEntryPoint, CallType, EntryPointExecutionContext};
 use crate::execution::native::utils::encode_str_as_felts;
 use crate::execution::syscalls::hint_processor::{SyscallCounter, OUT_OF_GAS_ERROR};
 use crate::execution::syscalls::SyscallSelector;
@@ -69,13 +72,11 @@ impl<'state> NativeSyscallHandler<'state> {
         }
     }
 
-    #[allow(dead_code)]
     fn increment_syscall_count_by(&mut self, selector: &SyscallSelector, n: usize) {
         let syscall_count = self.syscall_counter.entry(*selector).or_default();
         *syscall_count += n
     }
 
-    #[allow(dead_code)]
     fn execute_inner_call(
         &mut self,
         entry_point: CallEntryPoint,
@@ -171,12 +172,36 @@ impl<'state> StarknetSyscallHandler for &mut NativeSyscallHandler<'state> {
 
     fn library_call(
         &mut self,
-        _class_hash: Felt,
-        _function_selector: Felt,
-        _calldata: &[Felt],
-        _remaining_gas: &mut u128,
+        class_hash: Felt,
+        function_selector: Felt,
+        calldata: &[Felt],
+        remaining_gas: &mut u128,
     ) -> SyscallResult<Vec<Felt>> {
-        todo!("Implement library_call syscall.");
+        self.substract_syscall_gas_cost(
+            remaining_gas,
+            SyscallSelector::LibraryCall,
+            self.context.gas_costs().library_call_gas_cost,
+        )?;
+
+        let class_hash = ClassHash(class_hash);
+
+        let wrapper_calldata = Calldata(Arc::new(calldata.to_vec()));
+
+        let entry_point = CallEntryPoint {
+            class_hash: Some(class_hash),
+            code_address: None,
+            entry_point_type: EntryPointType::External,
+            entry_point_selector: EntryPointSelector(function_selector),
+            calldata: wrapper_calldata,
+            // The call context remains the same in a library call.
+            storage_address: self.contract_address,
+            caller_address: self.caller_address,
+            call_type: CallType::Delegate,
+            initial_gas: u64::try_from(*remaining_gas)
+                .expect("Failed to convert gas (u128 -> u64)"),
+        };
+
+        Ok(self.execute_inner_call(entry_point, remaining_gas)?.0)
     }
 
     fn call_contract(
diff --git a/crates/blockifier/src/execution/syscalls/syscall_tests/library_call.rs b/crates/blockifier/src/execution/syscalls/syscall_tests/library_call.rs
index e6eda072d6..c0d590d094 100644
--- a/crates/blockifier/src/execution/syscalls/syscall_tests/library_call.rs
+++ b/crates/blockifier/src/execution/syscalls/syscall_tests/library_call.rs
@@ -29,6 +29,7 @@ use crate::test_utils::{
 };
 use crate::versioned_constants::VersionedConstants;
 
+#[test_case(FeatureContract::TestContract(CairoVersion::Native), 189470; "Native")]
 #[test_case(FeatureContract::TestContract(CairoVersion::Cairo1), REQUIRED_GAS_LIBRARY_CALL_TEST; "VM")]
 fn test_library_call(test_contract: FeatureContract, expected_gas: u64) {
     let chain_info = &ChainInfo::create_for_testing();
@@ -60,6 +61,7 @@ fn test_library_call(test_contract: FeatureContract, expected_gas: u64) {
     );
 }
 
+#[test_case(FeatureContract::TestContract(CairoVersion::Native); "Native")]
 #[test_case(FeatureContract::TestContract(CairoVersion::Cairo1); "VM")]
 fn test_library_call_assert_fails(test_contract: FeatureContract) {
     let chain_info = &ChainInfo::create_for_testing();
@@ -81,12 +83,18 @@ fn test_library_call_assert_fails(test_contract: FeatureContract) {
 
     let call_info = entry_point_call.execute_directly(&mut state).unwrap();
     assert!(call_info.execution.failed);
-    assert_eq!(
-        format_panic_data(&call_info.execution.retdata.0),
-        "(0x7820213d2079 ('x != y'), 0x454e545259504f494e545f4641494c4544 ('ENTRYPOINT_FAILED'))"
-    );
+
+    let expected_err = match test_contract.cairo_version() {
+        CairoVersion::Cairo0 | CairoVersion::Cairo1 => {
+            "(0x7820213d2079 ('x != y'), 0x454e545259504f494e545f4641494c4544 \
+             ('ENTRYPOINT_FAILED'))"
+        }
+        CairoVersion::Native => "0x7820213d2079 ('x != y')",
+    };
+    assert_eq!(format_panic_data(&call_info.execution.retdata.0), expected_err);
 }
 
+#[test_case(FeatureContract::TestContract(CairoVersion::Native), 518110; "Native")]
 #[test_case(FeatureContract::TestContract(CairoVersion::Cairo1), 478110; "VM")]
 fn test_nested_library_call(test_contract: FeatureContract, expected_gas: u64) {
     let chain_info = &ChainInfo::create_for_testing();