From 50adff8a525e2c6ee2d8bd5c141d123806cd28f7 Mon Sep 17 00:00:00 2001 From: Bhargava Shastry Date: Tue, 30 Sep 2025 10:24:50 +0200 Subject: [PATCH 1/2] test(tests): add BLOCKHASH genesis hash availability test Add regression test verifying BLOCKHASH(0) returns genesis hash in block 1. Tests blockchain test infrastructure properly populates genesis hash before execution, preventing BLOCKHASH(0) from returning 0. Regression context: revm blockchaintest runner wasn't inserting block_hashes into state, causing BLOCKHASH(0) to return 0. This broke tests with dynamic address computations like BLOCKHASH(0) | TIMESTAMP, where the computed address would be incorrect, leading to balance transfer failures. Test validates infrastructure setup by storing ISZERO(BLOCKHASH(0)) which should be 0 (false) when genesis hash is properly available. --- tests/frontier/opcodes/test_blockhash.py | 57 ++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 tests/frontier/opcodes/test_blockhash.py diff --git a/tests/frontier/opcodes/test_blockhash.py b/tests/frontier/opcodes/test_blockhash.py new file mode 100644 index 00000000000..3d89bb61602 --- /dev/null +++ b/tests/frontier/opcodes/test_blockhash.py @@ -0,0 +1,57 @@ +"""Tests for BLOCKHASH opcode.""" + +import pytest + +from ethereum_test_tools import ( + Account, + Alloc, + Block, + BlockchainTestFiller, + Storage, + Transaction, +) +from ethereum_test_tools import Opcodes as Op + + +@pytest.mark.valid_from("Frontier") +def test_genesis_hash_available(blockchain_test: BlockchainTestFiller, pre: Alloc): + """ + Verify BLOCKHASH(0) returns genesis hash in block 1. + + Regression test: Blockchain test infrastructure must populate genesis hash + before execution. Without this, BLOCKHASH(0) returns 0, breaking dynamic + address computations like BLOCKHASH(0) | TIMESTAMP. + + Bug context: revm blockchaintest runner wasn't inserting block_hashes, + causing failures in tests with BLOCKHASH-derived addresses. + """ + storage = Storage() + + # Store ISZERO(BLOCKHASH(0)) - should be 0 (false) if genesis hash exists + code = Op.SSTORE(storage.store_next(0), Op.ISZERO(Op.BLOCKHASH(0))) + + contract = pre.deploy_contract(code=code) + sender = pre.fund_eoa() + + blocks = [ + Block( + txs=[ + Transaction( + sender=sender, + to=contract, + gas_limit=100_000, + protected=False, + ) + ] + ) + ] + + post = { + contract: Account( + storage={ + 0: 0, # ISZERO(BLOCKHASH(0)) should be 0 (genesis hash exists and is non-zero) + } + ) + } + + blockchain_test(pre=pre, post=post, blocks=blocks) From d2fadd8f8e37e0bd1033a8dc48c51d1753c8d37f Mon Sep 17 00:00:00 2001 From: Bhargava Shastry Date: Wed, 1 Oct 2025 10:14:25 +0200 Subject: [PATCH 2/2] test(tests): extend BLOCKHASH test to verify block 1 hash availability MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Extends test_genesis_hash_available to verify both genesis (block 0) and first executed block (block 1) hash insertion by adding a second block that calls the contract, testing BLOCKHASH(0) and BLOCKHASH(1). Addresses PR feedback to test complete block hash infrastructure. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude --- tests/frontier/opcodes/test_blockhash.py | 31 ++++++++++++++++++------ 1 file changed, 24 insertions(+), 7 deletions(-) diff --git a/tests/frontier/opcodes/test_blockhash.py b/tests/frontier/opcodes/test_blockhash.py index 3d89bb61602..f213f791b55 100644 --- a/tests/frontier/opcodes/test_blockhash.py +++ b/tests/frontier/opcodes/test_blockhash.py @@ -16,19 +16,25 @@ @pytest.mark.valid_from("Frontier") def test_genesis_hash_available(blockchain_test: BlockchainTestFiller, pre: Alloc): """ - Verify BLOCKHASH(0) returns genesis hash in block 1. + Verify BLOCKHASH returns genesis and block 1 hashes. - Regression test: Blockchain test infrastructure must populate genesis hash - before execution. Without this, BLOCKHASH(0) returns 0, breaking dynamic + Regression test: Blockchain test infrastructure must populate block hashes + before execution. Without this, BLOCKHASH returns 0, breaking dynamic address computations like BLOCKHASH(0) | TIMESTAMP. + Tests both genesis (block 0) and first executed block (block 1) hash + insertion by calling the contract in block 2. + Bug context: revm blockchaintest runner wasn't inserting block_hashes, causing failures in tests with BLOCKHASH-derived addresses. """ storage = Storage() - # Store ISZERO(BLOCKHASH(0)) - should be 0 (false) if genesis hash exists - code = Op.SSTORE(storage.store_next(0), Op.ISZERO(Op.BLOCKHASH(0))) + # Store ISZERO(BLOCKHASH(0)) and ISZERO(BLOCKHASH(1)) + # Both should be 0 (false) if hashes exist + code = Op.SSTORE(storage.store_next(0), Op.ISZERO(Op.BLOCKHASH(0))) + Op.SSTORE( + storage.store_next(0), Op.ISZERO(Op.BLOCKHASH(1)) + ) contract = pre.deploy_contract(code=code) sender = pre.fund_eoa() @@ -43,13 +49,24 @@ def test_genesis_hash_available(blockchain_test: BlockchainTestFiller, pre: Allo protected=False, ) ] - ) + ), + Block( + txs=[ + Transaction( + sender=sender, + to=contract, + gas_limit=100_000, + protected=False, + ) + ] + ), ] post = { contract: Account( storage={ - 0: 0, # ISZERO(BLOCKHASH(0)) should be 0 (genesis hash exists and is non-zero) + 0: 0, # ISZERO(BLOCKHASH(0)) = 0 (genesis hash exists) + 1: 0, # ISZERO(BLOCKHASH(1)) = 0 (block 1 hash exists) } ) }