fix(anvil): reset cache path during anvil_reset without fork url

[nbaztec]

Motivation

The test test_reset_dev_account_nonce would fail on subsequent runs because anvil_reset when run without a fork_url would not update the cache path in SharedBackend and BlockchainDb. As such, after reset, the rpc calls would write to the initial block's cache file.

Solution

Reset the ForkedDatabase correctly even when the fork url is missing.

Note

Unsure why this doesn't fail on the CI, but it would consistently fail locally on Ubuntu 24.04

[grandizzy]

makes sense, thank you! left couple of nits

[grandizzy]

this makes sense, can you please externalize this code (which is done also in the case of rpc url specified) in a helper fn / closure and reuse?

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

Lines 531 to 534 in f399820

	if let Some(fork_url) = forking.json_rpc_url {
	// Set the fork block number
	let mut node_config = self.node_config.write().await;
	node_config.fork_choice = Some(ForkChoice::Block(fork_block_number));

[grandizzy]

can we simplify this by starting node with cache_path config?

foundry/crates/anvil/src/config.rs

Lines 967 to 972 in 9f11e6d

	/// Sets the path where states are cached
	#[must_use]
	pub fn with_cache_path(mut self, cache_path: Option<PathBuf>) -> Self {
	self.cache_path = cache_path;
	self
	}

[nbaztec]

The test actually verifies that the cache path is updated upon reset, the regex exists because cache_path is currently private (so only obtainable via fmt::Debug). If we expose that property we can get rid of the regex and check it straight away