Testing

Configuration related to the behavior of forge test.

Sections

General

verbosity
  • Type: integer
  • Default: 0
  • Environment: FOUNDRY_VERBOSITY or DAPP_VERBOSITY

The verbosity level to use during tests.

  • Level 2 (-vv): Logs emitted during tests are also displayed.
  • Level 3 (-vvv): Stack traces for failing tests are also displayed.
  • Level 4 (-vvvv): Stack traces for all tests are displayed, and setup traces for failing tests are displayed.
  • Level 5 (-vvvvv): Stack traces and setup traces are always displayed.
ffi
  • Type: boolean
  • Default: false
  • Environment: FOUNDRY_FFI or DAPP_FFI

Whether or not to enable the ffi cheatcode.

Warning: Enabling this cheatcode has security implications for your project, as it allows tests to execute arbitrary programs on your computer.

sender
  • Type: string (address)
  • Default: 0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38
  • Environment: FOUNDRY_SENDER or DAPP_SENDER

The value of msg.sender in tests.

tx_origin
  • Type: string (address)
  • Default: 0x1804c8AB1F12E6bbf3894d4083f33e07309d1f38
  • Environment: FOUNDRY_TX_ORIGIN or DAPP_TX_ORIGIN

The value of tx.origin in tests.

initial_balance
  • Type: string (hexadecimal)
  • Default: 0xffffffffffffffffffffffff
  • Environment: FOUNDRY_INITIAL_BALANCE or DAPP_INITIAL_BALANCE

The initial balance of the test contracts in wei, written in hexadecimal.

block_number
  • Type: integer
  • Default: 1
  • Environment: FOUNDRY_BLOCK_NUMBER or DAPP_BLOCK_NUMBER

The value of block.number in tests.

chain_id
  • Type: integer
  • Default: 31337
  • Environment: FOUNDRY_CHAIN_ID or DAPP_CHAIN_ID

The value of the chainid opcode in tests.

gas_limit
  • Type: integer or string
  • Default: 9223372036854775807
  • Environment: FOUNDRY_GAS_LIMIT or DAPP_GAS_LIMIT

The gas limit for each test case.

ℹ️ Note

Due to a limitation in a dependency of Forge, you cannot raise the gas limit beyond the default without changing the value to a string.

In order to use higher gas limits use a string:

gas_limit = "18446744073709551615" # u64::MAX
gas_price
  • Type: integer
  • Default: 0
  • Environment: FOUNDRY_GAS_PRICE or DAPP_GAS_PRICE

The price of gas (in wei) in tests.

block_base_fee_per_gas
  • Type: integer
  • Default: 0
  • Environment: FOUNDRY_BLOCK_BASE_FEE_PER_GAS or DAPP_BLOCK_BASE_FEE_PER_GAS

The base fee per gas (in wei) in tests.

block_coinbase
  • Type: string (address)
  • Default: 0x0000000000000000000000000000000000000000
  • Environment: FOUNDRY_BLOCK_COINBASE or DAPP_BLOCK_COINBASE

The value of block.coinbase in tests.

block_timestamp
  • Type: integer
  • Default: 1
  • Environment: FOUNDRY_BLOCK_TIMESTAMP or DAPP_BLOCK_TIMESTAMP

The value of block.timestamp in tests.

block_difficulty
  • Type: integer
  • Default: 0
  • Environment: FOUNDRY_BLOCK_DIFFICULTY or DAPP_BLOCK_DIFFICULTY

The value of block.difficulty in tests.

gas_reports
  • Type: array of strings (contract names)
  • Default: [“*”]
  • Environment: FOUNDRY_GAS_REPORTS or DAPP_GAS_REPORTS

The contracts to print gas reports for.

no_storage_caching
  • Type: boolean
  • Default: false
  • Environment: FOUNDRY_NO_STORAGE_CACHING or DAPP_NO_STORAGE_CACHING

If set to true, then block data from RPC endpoints in tests will not be cached. Otherwise, the data is cached to $HOME/.foundry/cache/<chain id>/<block number>.

[rpc_storage_caching]

The [rpc_storage_caching] block determines what RPC endpoints are cached.

rpc_storage_caching.chains
  • Type: string or array of strings (chain names)
  • Default: all
  • Environment: N/A

Determines what chains are cached. By default, all chains are cached.

Valid values are:

  • “all”
  • A list of chain names, e.g. ["optimism", "mainnet"]
rpc_storage_caching.endpoints
  • Type: string or array of regex patterns (to match URLs)
  • Default: remote
  • Environment: N/A

Determines what RPC endpoints are cached. By default, only remote endpoints are cached.

Valid values are:

  • all
  • remote (default)
  • A list of regex patterns, e.g. ["localhost"]
eth_rpc_url
  • Type: string
  • Default: none
  • Environment: FOUNDRY_ETH_RPC_URL or DAPP_ETH_RPC_URL

The url of the rpc server that should be used for any rpc calls.

etherscan_api_key
  • Type: string
  • Default: none
  • Environment: FOUNDRY_ETHERSCAN_API_KEY or DAPP_ETHERSCAN_API_KEY

The etherscan API key for RPC calls.

match-test
  • Type: regex
  • Default: none
  • Environment: FOUNDRY_MATCH_TEST or DAPP_MATCH_TEST

Only run test methods matching regex. Equivalent to forge test --match-test <TEST_PATTERN>

no-match-test
  • Type: regex
  • Default: none
  • Environment: FOUNDRY_NO_MATCH_TEST or DAPP_NO_MATCH_TEST

Only run test methods not matching regex. Equivalent to forge test --no-match-test <TEST_PATTERN_INVERSE>

match-contract
  • Type: regex
  • Default: none
  • Environment: FOUNDRY_MATCH_CONTRACT or DAPP_MATCH_CONTRACT

Only run test methods in contracts matching regex. Equivalent to forge test --match-contract <CONTRACT_PATTERN>

no-match-contract
  • Type: regex
  • Default: none
  • Environment: FOUNDRY_NO_MATCH_CONTRACT or DAPP_NO_MATCH_CONTRACT

Only run test methods in contracts not matching regex. Equivalent to forge test --no-match-contract <CONTRACT_PATTERN_INVERSE>

match-path
  • Type: regex
  • Default: none
  • Environment: FOUNDRY_MATCH_PATH or DAPP_MATCH_PATH

Only runs test methods on files matching the path. Equivalent to forge test --match-path <PATH_PATTERN>

no-match-path
  • Type: regex
  • Default: none
  • Environment: FOUNDRY_NO_MATCH_PATH or DAPP_NO_MATCH_PATH

Only runs test methods on files not matching the path. Equivalent to forge test --no-match-path <PATH_PATTERN_INVERSE>

block_gas_limit
  • Type: integer
  • Default: none
  • Environment: FOUNDRY_BLOCK_GAS_LIMIT or DAPP_BLOCK_GAS_LIMIT

The block.gaslimit value during EVM execution.

memory_limit
  • Type: integer
  • Default: 33554432
  • Environment: FOUNDRY_MEMORY_LIMIT or DAPP_MEMORY_LIMIT

The memory limit of the EVM in bytes.

names
  • Type: boolean
  • Default: false
  • Environment: FOUNDRY_NAMES or DAPP_NAMES

Print compiled contract names.

sizes
  • Type: boolean
  • Default: false
  • Environment: FOUNDRY_SIZES or DAPP_SIZES

Print compiled contract sizes.

rpc_endpoints
  • Type: table of RPC endpoints
  • Default: none
  • Environment: none

This section lives outside of profiles and defines a table of RPC endpoints, where the key specifies the RPC endpoints’s name and the value is the RPC endpoint itself.

The value can either be a valid RPC endpoint or a reference to an environment variable (wrapped with in ${}).

These RPC endpoints can be used in tests and Solidity scripts (see vm.rpc).

The following example defines an endpoint named optimism and an endpoint named mainnet that references an environment variable RPC_MAINNET:

[rpc_endpoints]
optimism = "https://optimism.alchemyapi.io/v2/..."
mainnet = "${RPC_MAINNET}"
prompt_timeout
  • Type: integer
  • Default: 120
  • Environment: FOUNDRY_PROMPT_TIMEOUT

The number of seconds to wait before vm.prompt reverts with a timeout.

Fuzz

Configuration values for [fuzz] section.

runs
  • Type: integer
  • Default: 256
  • Environment: FOUNDRY_FUZZ_RUNS or DAPP_FUZZ_RUNS

The amount of fuzz runs to perform for each fuzz test case. Higher values gives more confidence in results at the cost of testing speed.

max_test_rejects
  • Type: integer
  • Default: 65536
  • Environment: FOUNDRY_FUZZ_MAX_TEST_REJECTS

The maximum number of combined inputs that may be rejected before the test as a whole aborts. “Global” filters apply to the whole test case. If the test case is rejected, the whole thing is regenerated.

seed
  • Type: string (hexadecimal)
  • Default: none
  • Environment: FOUNDRY_FUZZ_SEED

Optional seed for the fuzzing RNG algorithm.

dictionary_weight
  • Type: integer (between 0 and 100)
  • Default: 40
  • Environment: FOUNDRY_FUZZ_DICTIONARY_WEIGHT

The weight of the dictionary. A higher dictionary weight will bias the fuzz inputs towards “interesting” values, e.g. boundary values like type(uint256).max or contract addresses from your environment.

include_storage
  • Type: boolean
  • Default: true
  • Environment: FOUNDRY_FUZZ_INCLUDE_STORAGE

The flag indicating whether to include values from storage.

include_push_bytes
  • Type: boolean
  • Default: true
  • Environment: FOUNDRY_FUZZ_INCLUDE_PUSH_BYTES

The flag indicating whether to include push bytes values.

Invariant

Configuration values for [invariant] section.

ℹ️ Note

Configuration for [invariant] section has the fallback logic for common config entries (runs, seed, dictionary_weight etc).

  • If the entries are not set in either section, then the defaults will be used.
  • If the entries are set in the [fuzz] section, but are not set in the [invariant] section, these values will automatically be set to the values specified in the [fuzz] section.
  • For any profile other than default:
    • If at least one entry is set in the [invariant] (same as [profile.default.invariant]) section, then the values from [invariant] section will be used, including defaults.
    • If no entry is set in the [invariant] section, but there are entries in the [fuzz] (same as [profile.default.fuzz]) section, then the values from the [fuzz] section will be used.
    • If it’s none of the cases described above, then the defaults will be used.
runs
  • Type: integer
  • Default: 256
  • Environment: FOUNDRY_INVARIANT_RUNS

The number of runs that must execute for each invariant test group. See also fuzz.runs

depth
  • Type: integer
  • Default: 15
  • Environment: FOUNDRY_INVARIANT_DEPTH

The number of calls executed to attempt to break invariants in one run.

fail_on_revert
  • Type: boolean
  • Default: false
  • Environment: FOUNDRY_INVARIANT_FAIL_ON_REVERT

Fails the invariant fuzzing if a revert occurs.

call_override
  • Type: boolean
  • Default: false
  • Environment: FOUNDRY_INVARIANT_CALL_OVERRIDE

Overrides unsafe external calls when running invariant tests, useful for e.g. performing reentrancy checks.

dictionary_weight
  • Type: integer (between 0 and 100)
  • Default: 80
  • Environment: FOUNDRY_INVARIANT_DICTIONARY_WEIGHT

The weight of the dictionary. See also fuzz.dictionary_weight

include_storage
  • Type: boolean
  • Default: true
  • Environment: FOUNDRY_FUZZ_INCLUDE_STORAGE

The flag indicating whether to include values from storage. See also fuzz.include_storage

include_push_bytes
  • Type: boolean
  • Default: true
  • Environment: FOUNDRY_FUZZ_INCLUDE_PUSH_BYTES

The flag indicating whether to include push bytes values. See also fuzz.include_push_bytes