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Test CALL AND CALLCODE Gas Calculation

Documentation for tests/frontier/opcodes/test_call_and_callcode_gas_calculation.py@49c766fb.

Generate fixtures for these test cases for Prague with:

fill -v tests/frontier/opcodes/test_call_and_callcode_gas_calculation.py --fork Prague
Tests the nested CALL/CALLCODE opcode gas consumption with a positive value transfer.

This test is designed to investigate an issue identified in EthereumJS, as reported in: ethereumjs/ethereumjs-monorepo#3194.

The issue pertains to the incorrect gas calculation for CALL/CALLCODE operations with a positive value transfer, due to the pre-addition of the gas stipend (2300) to the currently available gas instead of adding it to the new call frame. This bug was specific to the case where insufficient gas was provided for the CALL/CALLCODE operation. Due to the pre-addition of the stipend to the currently available gas, the case for insufficient gas was not properly failing with an out-of-gas error.

Test setup: Given two smart contract accounts, 0x0A (caller) and 0x0B (callee): 1) An arbitrary transaction calls into the contract 0x0A. 2) Contract 0x0A executes a CALL to contract 0x0B with a specific gas limit (X). 3) Contract 0x0B then attempts a CALL/CALLCODE to a non-existent contract 0x0C, with a positive value transfer (activating the gas stipend). 4) If the gas X provided by contract 0x0A to 0x0B is sufficient, contract 0x0B will push 0x01 onto the stack after returning to the call frame in 0x0A. Otherwise, it should push 0x00, indicating the insufficiency of gas X (for the bug in EthereumJS, the CALL/CALLCODE operation would return 0x01 due to the pre-addition of the gas stipend). 5) The resulting stack value is saved into contract 0x0A's storage, allowing us to verify whether the provided gas was sufficient or insufficient.

Test Functions Overview

Name Type Cases (Prague) Description
test_value_transfer_gas_calculation state_test 0 Tests the nested CALL/CALLCODE opcode gas consumption with a positive value transfer.