Next block after evm_revert does not have increased timestamp

[michprev]

Component

Anvil

Have you ensured that all of these are up to date?

• Foundry
• Foundryup

What version of Foundry are you on?

anvil 0.1.0 (25d3ce7 2023-08-01T00:20:13.496244391Z)

What command(s) is the bug in?

anvil --prune-history 100 --steps-tracing --silent --port 36655

Operating System

Linux

Describe the bug

It seems that the next block mined after an evm_revert JSON-RPC request does not have the timestamp increased. I believe this can be considered a bug since timestamps of blocks mined without evm_snapshot and evm_revert are always increased by 1.

I think this may be the relevant part of the code:

foundry/anvil/src/eth/backend/mem/mod.rs

Lines 625 to 629 in 9a4bb7f

	// Note: In [`TimeManager::compute_next_timestamp`] we ensure that the next timestamp is
	// always increasing by at least one. By subtracting 1 here, this is mitigated.
	let reset_time = block.timestamp.as_u64().saturating_sub(1);
	self.time.reset(reset_time);
	self.set_block_number(num.into());

The current behavior is (described in Woke testing framework):

from woke.testing import *

@default_chain.connect()
def test_reverting():
    t1 = default_chain.blocks["latest"].timestamp
    with default_chain.snapshot_and_revert():
        default_chain.mine()

    t2 = default_chain.blocks["latest"].timestamp
    assert t1 == t2

    default_chain.mine()
    t3 = default_chain.blocks["latest"].timestamp
    assert t3 == t2

while the expected behavior is

    assert t3 == t2 + 1

[mattsse]

@Evalir I think the self.time.reset(reset_time); is the culprit here

[Evalir]

Hey @michprev — i cannot seem reproduce this either manually or with woke. i haven't used woke before, maybe you can provide a repo that i can clone and run the test to detect this?

[michprev]

Hey @Evalir, I have modified the script to call eth_getBlockByNumber directly to provide a proof the issue is not in the testing framework.

The steps to reproduce the issue are:

1. pip3 install -U woke
2. Create test_xyz.py containing the Python code below
3. Run woke test test_xyz.py

The script:

import logging
from woke.testing import *
from woke.development.json_rpc.communicator import logger

@default_chain.connect()
def test_reverting():
    logger.setLevel(logging.INFO)

    t1 = int(default_chain.chain_interface.get_block("latest")['timestamp'], 16)
    with default_chain.snapshot_and_revert():
        default_chain.mine()

    t2 = int(default_chain.chain_interface.get_block("latest")['timestamp'], 16)
    assert t1 == t2

    default_chain.mine()
    t3 = int(default_chain.chain_interface.get_block("latest")['timestamp'], 16)
    assert t3 == t2 + 1

The script now performs full logging of JSON-RPC communication. I am attaching the log file. Please take a look at requests with id 14 and 16 (eth_getBlockByNumber). Both blocks have the same timestamp but a different block number.
log.txt

[klkvr]

Confirming that issue was the case on 25d3ce7 but is fixed now