ethereum.forks.bpo3.stateethereum.forks.bpo4.state
State.
.. contents:: Table of Contents :backlinks: none :local:
Introduction
The state contains all information that is preserved between transactions.
It consists of a main account trie and storage tries for each contract.
There is a distinction between an account that does not exist and
EMPTY_ACCOUNT.
State ¶
Contains all information that is preserved between transactions.
| 38 | @dataclass |
|---|
class State:
_main_trie¶
| 44 | _main_trie: Trie[Address, Optional[Account]] = field( |
|---|---|
| 45 | default_factory=lambda: Trie(secured=True, default=None) |
| 46 | ) |
_storage_tries¶
| 47 | _storage_tries: Dict[Address, Trie[Bytes32, U256]] = field( |
|---|---|
| 48 | default_factory=dict |
| 49 | ) |
_snapshots¶
| 50 | _snapshots: List[ |
|---|---|
| 51 | Tuple[ |
| 52 | Trie[Address, Optional[Account]], |
| 53 | Dict[Address, Trie[Bytes32, U256]], |
| 54 | ] |
| 55 | ] = field(default_factory=list) |
created_accounts¶
| 56 | created_accounts: Set[Address] = field(default_factory=set) |
|---|
_code_store¶
| 57 | _code_store: Dict[Hash32, Bytes] = field( |
|---|---|
| 58 | default_factory=dict, compare=False |
| 59 | ) |
get_code ¶
Get the bytecode for a given code hash.
Return b"" for EMPTY_CODE_HASH.
def get_code(self, code_hash: Hash32) -> Bytes:
| 62 | """ |
|---|---|
| 63 | Get the bytecode for a given code hash. |
| 64 | |
| 65 | Return ``b""`` for ``EMPTY_CODE_HASH``. |
| 66 | """ |
| 67 | if code_hash == EMPTY_CODE_HASH: |
| 68 | return b"" |
| 69 | return self._code_store[code_hash] |
TransientStorage ¶
Contains all information that is preserved between message calls within a transaction.
| 72 | @dataclass |
|---|
class TransientStorage:
_tries¶
| 79 | _tries: Dict[Address, Trie[Bytes32, U256]] = field(default_factory=dict) |
|---|
_snapshots¶
| 80 | _snapshots: List[Dict[Address, Trie[Bytes32, U256]]] = field( |
|---|---|
| 81 | default_factory=list |
| 82 | ) |
close_state ¶
Free resources held by the state. Used by optimized implementations to release file descriptors.
def close_state(state: State) -> None:
| 86 | """ |
|---|---|
| 87 | Free resources held by the state. Used by optimized implementations to |
| 88 | release file descriptors. |
| 89 | """ |
| 90 | del state._main_trie |
| 91 | del state._storage_tries |
| 92 | del state._snapshots |
| 93 | del state.created_accounts |
| 94 | del state._code_store |
begin_transaction ¶
Start a state transaction.
Transactions are entirely implicit and can be nested. It is not possible to calculate the state root during a transaction.
Parameters
state : State The state. transient_storage : TransientStorage The transient storage of the transaction.
def begin_transaction(state: State, transient_storage: TransientStorage) -> None:
| 100 | """ |
|---|---|
| 101 | Start a state transaction. |
| 102 | |
| 103 | Transactions are entirely implicit and can be nested. It is not possible to |
| 104 | calculate the state root during a transaction. |
| 105 | |
| 106 | Parameters |
| 107 | ---------- |
| 108 | state : State |
| 109 | The state. |
| 110 | transient_storage : TransientStorage |
| 111 | The transient storage of the transaction. |
| 112 | |
| 113 | """ |
| 114 | state._snapshots.append( |
| 115 | ( |
| 116 | copy_trie(state._main_trie), |
| 117 | {k: copy_trie(t) for (k, t) in state._storage_tries.items()}, |
| 118 | ) |
| 119 | ) |
| 120 | transient_storage._snapshots.append( |
| 121 | {k: copy_trie(t) for (k, t) in transient_storage._tries.items()} |
| 122 | ) |
commit_transaction ¶
Commit a state transaction.
Parameters
state : State The state. transient_storage : TransientStorage The transient storage of the transaction.
def commit_transaction(state: State, transient_storage: TransientStorage) -> None:
| 128 | """ |
|---|---|
| 129 | Commit a state transaction. |
| 130 | |
| 131 | Parameters |
| 132 | ---------- |
| 133 | state : State |
| 134 | The state. |
| 135 | transient_storage : TransientStorage |
| 136 | The transient storage of the transaction. |
| 137 | |
| 138 | """ |
| 139 | state._snapshots.pop() |
| 140 | if not state._snapshots: |
| 141 | state.created_accounts.clear() |
| 142 | |
| 143 | transient_storage._snapshots.pop() |
rollback_transaction ¶
Rollback a state transaction, resetting the state to the point when the
corresponding begin_transaction() call was made.
Parameters
state : State The state. transient_storage : TransientStorage The transient storage of the transaction.
def rollback_transaction(state: State, transient_storage: TransientStorage) -> None:
| 149 | """ |
|---|---|
| 150 | Rollback a state transaction, resetting the state to the point when the |
| 151 | corresponding `begin_transaction()` call was made. |
| 152 | |
| 153 | Parameters |
| 154 | ---------- |
| 155 | state : State |
| 156 | The state. |
| 157 | transient_storage : TransientStorage |
| 158 | The transient storage of the transaction. |
| 159 | |
| 160 | """ |
| 161 | state._main_trie, state._storage_tries = state._snapshots.pop() |
| 162 | if not state._snapshots: |
| 163 | state.created_accounts.clear() |
| 164 | |
| 165 | transient_storage._tries = transient_storage._snapshots.pop() |
get_account ¶
Get the Account object at an address. Returns EMPTY_ACCOUNT if there
is no account at the address.
Use get_account_optional() if you care about the difference between a
non-existent account and EMPTY_ACCOUNT.
Parameters
state: State
The state
address : Address
Address to lookup.
Returns
account : Account
Account at address.
def get_account(state: State, address: Address) -> Account:
| 169 | """ |
|---|---|
| 170 | Get the `Account` object at an address. Returns `EMPTY_ACCOUNT` if there |
| 171 | is no account at the address. |
| 172 | |
| 173 | Use `get_account_optional()` if you care about the difference between a |
| 174 | non-existent account and `EMPTY_ACCOUNT`. |
| 175 | |
| 176 | Parameters |
| 177 | ---------- |
| 178 | state: `State` |
| 179 | The state |
| 180 | address : `Address` |
| 181 | Address to lookup. |
| 182 | |
| 183 | Returns |
| 184 | ------- |
| 185 | account : `Account` |
| 186 | Account at address. |
| 187 | |
| 188 | """ |
| 189 | account = get_account_optional(state, address) |
| 190 | if isinstance(account, Account): |
| 191 | return account |
| 192 | else: |
| 193 | return EMPTY_ACCOUNT |
get_account_optional ¶
Get the Account object at an address. Returns None (rather than
EMPTY_ACCOUNT) if there is no account at the address.
Parameters
state: State
The state
address : Address
Address to lookup.
Returns
account : Account
Account at address.
def get_account_optional(state: State, address: Address) -> Optional[Account]:
| 197 | """ |
|---|---|
| 198 | Get the `Account` object at an address. Returns `None` (rather than |
| 199 | `EMPTY_ACCOUNT`) if there is no account at the address. |
| 200 | |
| 201 | Parameters |
| 202 | ---------- |
| 203 | state: `State` |
| 204 | The state |
| 205 | address : `Address` |
| 206 | Address to lookup. |
| 207 | |
| 208 | Returns |
| 209 | ------- |
| 210 | account : `Account` |
| 211 | Account at address. |
| 212 | |
| 213 | """ |
| 214 | account = trie_get(state._main_trie, address) |
| 215 | return account |
get_code ¶
Get the bytecode for a given code hash.
Return b"" for EMPTY_CODE_HASH.
def get_code(state: State, code_hash: Hash32) -> Bytes:
| 219 | """ |
|---|---|
| 220 | Get the bytecode for a given code hash. |
| 221 | |
| 222 | Return ``b""`` for ``EMPTY_CODE_HASH``. |
| 223 | """ |
| 224 | if code_hash == EMPTY_CODE_HASH: |
| 225 | return b"" |
| 226 | return state._code_store[code_hash] |
store_code ¶
Store bytecode in State and return its hash.
def store_code(state: State, code: Bytes) -> Hash32:
| 230 | """ |
|---|---|
| 231 | Store bytecode in ``State`` and return its hash. |
| 232 | """ |
| 233 | code_hash = keccak256(code) |
| 234 | if code_hash != EMPTY_CODE_HASH: |
| 235 | state._code_store[code_hash] = code |
| 236 | return code_hash |
set_account ¶
Set the Account object at an address. Setting to None deletes
the account (but not its storage, see destroy_account()).
Parameters
state: State
The state
address : Address
Address to set.
account : Account
Account to set at address.
def set_account(state: State, address: Address, account: Optional[Account]) -> None:
| 242 | """ |
|---|---|
| 243 | Set the `Account` object at an address. Setting to `None` deletes |
| 244 | the account (but not its storage, see `destroy_account()`). |
| 245 | |
| 246 | Parameters |
| 247 | ---------- |
| 248 | state: `State` |
| 249 | The state |
| 250 | address : `Address` |
| 251 | Address to set. |
| 252 | account : `Account` |
| 253 | Account to set at address. |
| 254 | |
| 255 | """ |
| 256 | trie_set(state._main_trie, address, account) |
destroy_account ¶
Completely remove the account at address and all of its storage.
This function is made available exclusively for the SELFDESTRUCT
opcode. It is expected that SELFDESTRUCT will be disabled in a future
hardfork and this function will be removed.
Parameters
state: State
The state
address : Address
Address of account to destroy.
def destroy_account(state: State, address: Address) -> None:
| 260 | """ |
|---|---|
| 261 | Completely remove the account at `address` and all of its storage. |
| 262 | |
| 263 | This function is made available exclusively for the `SELFDESTRUCT` |
| 264 | opcode. It is expected that `SELFDESTRUCT` will be disabled in a future |
| 265 | hardfork and this function will be removed. |
| 266 | |
| 267 | Parameters |
| 268 | ---------- |
| 269 | state: `State` |
| 270 | The state |
| 271 | address : `Address` |
| 272 | Address of account to destroy. |
| 273 | |
| 274 | """ |
| 275 | destroy_storage(state, address) |
| 276 | set_account(state, address, None) |
destroy_storage ¶
Completely remove the storage at address.
Parameters
state: State
The state
address : Address
Address of account whose storage is to be deleted.
def destroy_storage(state: State, address: Address) -> None:
| 280 | """ |
|---|---|
| 281 | Completely remove the storage at `address`. |
| 282 | |
| 283 | Parameters |
| 284 | ---------- |
| 285 | state: `State` |
| 286 | The state |
| 287 | address : `Address` |
| 288 | Address of account whose storage is to be deleted. |
| 289 | |
| 290 | """ |
| 291 | if address in state._storage_tries: |
| 292 | del state._storage_tries[address] |
mark_account_created ¶
Mark an account as having been created in the current transaction.
This information is used by get_storage_original() to handle an obscure
edgecase, and to respect the constraints added to SELFDESTRUCT by
EIP-6780.
The marker is not removed even if the account creation reverts. Since the
account cannot have had code prior to its creation and can't call
get_storage_original(), this is harmless.
Parameters
state: State
The state
address : Address
Address of the account that has been created.
def mark_account_created(state: State, address: Address) -> None:
| 296 | """ |
|---|---|
| 297 | Mark an account as having been created in the current transaction. |
| 298 | This information is used by `get_storage_original()` to handle an obscure |
| 299 | edgecase, and to respect the constraints added to SELFDESTRUCT by |
| 300 | EIP-6780. |
| 301 | |
| 302 | The marker is not removed even if the account creation reverts. Since the |
| 303 | account cannot have had code prior to its creation and can't call |
| 304 | `get_storage_original()`, this is harmless. |
| 305 | |
| 306 | Parameters |
| 307 | ---------- |
| 308 | state: `State` |
| 309 | The state |
| 310 | address : `Address` |
| 311 | Address of the account that has been created. |
| 312 | |
| 313 | """ |
| 314 | state.created_accounts.add(address) |
get_storage ¶
Get a value at a storage key on an account. Returns U256(0) if the
storage key has not been set previously.
Parameters
state: State
The state
address : Address
Address of the account.
key : Bytes
Key to lookup.
Returns
value : U256
Value at the key.
def get_storage(state: State, address: Address, key: Bytes32) -> U256:
| 318 | """ |
|---|---|
| 319 | Get a value at a storage key on an account. Returns `U256(0)` if the |
| 320 | storage key has not been set previously. |
| 321 | |
| 322 | Parameters |
| 323 | ---------- |
| 324 | state: `State` |
| 325 | The state |
| 326 | address : `Address` |
| 327 | Address of the account. |
| 328 | key : `Bytes` |
| 329 | Key to lookup. |
| 330 | |
| 331 | Returns |
| 332 | ------- |
| 333 | value : `U256` |
| 334 | Value at the key. |
| 335 | |
| 336 | """ |
| 337 | trie = state._storage_tries.get(address) |
| 338 | if trie is None: |
| 339 | return U256(0) |
| 340 | |
| 341 | value = trie_get(trie, key) |
| 342 | |
| 343 | assert isinstance(value, U256) |
| 344 | return value |
set_storage ¶
Set a value at a storage key on an account. Setting to U256(0) deletes
the key.
Parameters
state: State
The state
address : Address
Address of the account.
key : Bytes
Key to set.
value : U256
Value to set at the key.
def set_storage(state: State, address: Address, key: Bytes32, value: U256) -> None:
| 350 | """ |
|---|---|
| 351 | Set a value at a storage key on an account. Setting to `U256(0)` deletes |
| 352 | the key. |
| 353 | |
| 354 | Parameters |
| 355 | ---------- |
| 356 | state: `State` |
| 357 | The state |
| 358 | address : `Address` |
| 359 | Address of the account. |
| 360 | key : `Bytes` |
| 361 | Key to set. |
| 362 | value : `U256` |
| 363 | Value to set at the key. |
| 364 | |
| 365 | """ |
| 366 | assert trie_get(state._main_trie, address) is not None |
| 367 | |
| 368 | trie = state._storage_tries.get(address) |
| 369 | if trie is None: |
| 370 | trie = Trie(secured=True, default=U256(0)) |
| 371 | state._storage_tries[address] = trie |
| 372 | trie_set(trie, key, value) |
| 373 | if trie._data == {}: |
| 374 | del state._storage_tries[address] |
storage_root ¶
Calculate the storage root of an account.
Parameters
state: The state address : Address of the account.
Returns
root : Root
Storage root of the account.
def storage_root(state: State, address: Address) -> Root:
| 378 | """ |
|---|---|
| 379 | Calculate the storage root of an account. |
| 380 | |
| 381 | Parameters |
| 382 | ---------- |
| 383 | state: |
| 384 | The state |
| 385 | address : |
| 386 | Address of the account. |
| 387 | |
| 388 | Returns |
| 389 | ------- |
| 390 | root : `Root` |
| 391 | Storage root of the account. |
| 392 | |
| 393 | """ |
| 394 | assert not state._snapshots |
| 395 | if address in state._storage_tries: |
| 396 | return root(state._storage_tries[address]) |
| 397 | else: |
| 398 | return EMPTY_TRIE_ROOT |
state_root ¶
Calculate the state root.
Parameters
state: The current state.
Returns
root : Root
The state root.
def state_root(state: State) -> Root:
| 402 | """ |
|---|---|
| 403 | Calculate the state root. |
| 404 | |
| 405 | Parameters |
| 406 | ---------- |
| 407 | state: |
| 408 | The current state. |
| 409 | |
| 410 | Returns |
| 411 | ------- |
| 412 | root : `Root` |
| 413 | The state root. |
| 414 | |
| 415 | """ |
| 416 | assert not state._snapshots |
| 417 | |
| 418 | def get_storage_root(address: Address) -> Root: |
| 419 | return storage_root(state, address) |
| 420 | |
| 421 | return root(state._main_trie, get_storage_root=get_storage_root) |
account_exists ¶
Checks if an account exists in the state trie.
Parameters
state: The state address: Address of the account that needs to be checked.
Returns
account_exists : bool
True if account exists in the state trie, False otherwise
def account_exists(state: State, address: Address) -> bool:
| 425 | """ |
|---|---|
| 426 | Checks if an account exists in the state trie. |
| 427 | |
| 428 | Parameters |
| 429 | ---------- |
| 430 | state: |
| 431 | The state |
| 432 | address: |
| 433 | Address of the account that needs to be checked. |
| 434 | |
| 435 | Returns |
| 436 | ------- |
| 437 | account_exists : `bool` |
| 438 | True if account exists in the state trie, False otherwise |
| 439 | |
| 440 | """ |
| 441 | return get_account_optional(state, address) is not None |
account_has_code_or_nonce ¶
Checks if an account has non-zero nonce or non-empty code.
Parameters
state: The state address: Address of the account that needs to be checked.
Returns
has_code_or_nonce : bool
True if the account has non-zero nonce or non-empty code,
False otherwise.
def account_has_code_or_nonce(state: State, address: Address) -> bool:
| 445 | """ |
|---|---|
| 446 | Checks if an account has non-zero nonce or non-empty code. |
| 447 | |
| 448 | Parameters |
| 449 | ---------- |
| 450 | state: |
| 451 | The state |
| 452 | address: |
| 453 | Address of the account that needs to be checked. |
| 454 | |
| 455 | Returns |
| 456 | ------- |
| 457 | has_code_or_nonce : `bool` |
| 458 | True if the account has non-zero nonce or non-empty code, |
| 459 | False otherwise. |
| 460 | |
| 461 | """ |
| 462 | account = get_account(state, address) |
| 463 | return account.nonce != Uint(0) or account.code_hash != EMPTY_CODE_HASH |
account_has_storage ¶
Checks if an account has storage.
Parameters
state: The state address: Address of the account that needs to be checked.
Returns
has_storage : bool
True if the account has storage, False otherwise.
def account_has_storage(state: State, address: Address) -> bool:
| 467 | """ |
|---|---|
| 468 | Checks if an account has storage. |
| 469 | |
| 470 | Parameters |
| 471 | ---------- |
| 472 | state: |
| 473 | The state |
| 474 | address: |
| 475 | Address of the account that needs to be checked. |
| 476 | |
| 477 | Returns |
| 478 | ------- |
| 479 | has_storage : `bool` |
| 480 | True if the account has storage, False otherwise. |
| 481 | |
| 482 | """ |
| 483 | return address in state._storage_tries |
is_account_alive ¶
Check whether an account is both in the state and non-empty.
Parameters
state: The state address: Address of the account that needs to be checked.
Returns
is_alive : bool
True if the account is alive.
def is_account_alive(state: State, address: Address) -> bool:
| 487 | """ |
|---|---|
| 488 | Check whether an account is both in the state and non-empty. |
| 489 | |
| 490 | Parameters |
| 491 | ---------- |
| 492 | state: |
| 493 | The state |
| 494 | address: |
| 495 | Address of the account that needs to be checked. |
| 496 | |
| 497 | Returns |
| 498 | ------- |
| 499 | is_alive : `bool` |
| 500 | True if the account is alive. |
| 501 | |
| 502 | """ |
| 503 | account = get_account_optional(state, address) |
| 504 | return account is not None and account != EMPTY_ACCOUNT |
modify_state ¶
Modify an Account in the State. If, after modification, the account
exists and has zero nonce, empty code, and zero balance, it is destroyed.
def modify_state(state: State, address: Address, f: Callable[[Account], None]) -> None:
| 510 | """ |
|---|---|
| 511 | Modify an `Account` in the `State`. If, after modification, the account |
| 512 | exists and has zero nonce, empty code, and zero balance, it is destroyed. |
| 513 | """ |
| 514 | set_account(state, address, modify(get_account(state, address), f)) |
| 515 | |
| 516 | account = get_account_optional(state, address) |
| 517 | account_exists_and_is_empty = ( |
| 518 | account is not None |
| 519 | and account.nonce == Uint(0) |
| 520 | and account.code_hash == EMPTY_CODE_HASH |
| 521 | and account.balance == 0 |
| 522 | ) |
| 523 | |
| 524 | if account_exists_and_is_empty: |
| 525 | destroy_account(state, address) |
move_ether ¶
Move funds between accounts.
def move_ether(state: State, sender_address: Address, recipient_address: Address, amount: U256) -> None:
| 534 | """ |
|---|---|
| 535 | Move funds between accounts. |
| 536 | """ |
| 537 | |
| 538 | def reduce_sender_balance(sender: Account) -> None: |
| 539 | if sender.balance < amount: |
| 540 | raise AssertionError |
| 541 | sender.balance -= amount |
| 542 | |
| 543 | def increase_recipient_balance(recipient: Account) -> None: |
| 544 | recipient.balance += amount |
| 545 | |
| 546 | modify_state(state, sender_address, reduce_sender_balance) |
| 547 | modify_state(state, recipient_address, increase_recipient_balance) |
set_account_balance ¶
Sets the balance of an account.
Parameters
state: The current state.
address: Address of the account whose nonce needs to be incremented.
amount: The amount that needs to be set in the balance.
def set_account_balance(state: State, address: Address, amount: U256) -> None:
| 551 | """ |
|---|---|
| 552 | Sets the balance of an account. |
| 553 | |
| 554 | Parameters |
| 555 | ---------- |
| 556 | state: |
| 557 | The current state. |
| 558 | |
| 559 | address: |
| 560 | Address of the account whose nonce needs to be incremented. |
| 561 | |
| 562 | amount: |
| 563 | The amount that needs to be set in the balance. |
| 564 | |
| 565 | """ |
| 566 | |
| 567 | def set_balance(account: Account) -> None: |
| 568 | account.balance = amount |
| 569 | |
| 570 | modify_state(state, address, set_balance) |
increment_nonce ¶
Increments the nonce of an account.
Parameters
state: The current state.
address: Address of the account whose nonce needs to be incremented.
def increment_nonce(state: State, address: Address) -> None:
| 574 | """ |
|---|---|
| 575 | Increments the nonce of an account. |
| 576 | |
| 577 | Parameters |
| 578 | ---------- |
| 579 | state: |
| 580 | The current state. |
| 581 | |
| 582 | address: |
| 583 | Address of the account whose nonce needs to be incremented. |
| 584 | |
| 585 | """ |
| 586 | |
| 587 | def increase_nonce(sender: Account) -> None: |
| 588 | sender.nonce += Uint(1) |
| 589 | |
| 590 | modify_state(state, address, increase_nonce) |
set_code ¶
Sets Account code.
Parameters
state: The current state.
address: Address of the account whose code needs to be updated.
code: The bytecode that needs to be set.
def set_code(state: State, address: Address, code: Bytes) -> None:
| 594 | """ |
|---|---|
| 595 | Sets Account code. |
| 596 | |
| 597 | Parameters |
| 598 | ---------- |
| 599 | state: |
| 600 | The current state. |
| 601 | |
| 602 | address: |
| 603 | Address of the account whose code needs to be updated. |
| 604 | |
| 605 | code: |
| 606 | The bytecode that needs to be set. |
| 607 | |
| 608 | """ |
| 609 | code_hash = keccak256(code) |
| 610 | if code_hash != EMPTY_CODE_HASH: |
| 611 | state._code_store[code_hash] = code |
| 612 | |
| 613 | def write_code(sender: Account) -> None: |
| 614 | sender.code_hash = code_hash |
| 615 | |
| 616 | modify_state(state, address, write_code) |
get_storage_original ¶
Get the original value in a storage slot i.e. the value before the current transaction began. This function reads the value from the snapshots taken before executing the transaction.
Parameters
state: The current state. address: Address of the account to read the value from. key: Key of the storage slot.
def get_storage_original(state: State, address: Address, key: Bytes32) -> U256:
| 620 | """ |
|---|---|
| 621 | Get the original value in a storage slot i.e. the value before the current |
| 622 | transaction began. This function reads the value from the snapshots taken |
| 623 | before executing the transaction. |
| 624 | |
| 625 | Parameters |
| 626 | ---------- |
| 627 | state: |
| 628 | The current state. |
| 629 | address: |
| 630 | Address of the account to read the value from. |
| 631 | key: |
| 632 | Key of the storage slot. |
| 633 | |
| 634 | """ |
| 635 | # In the transaction where an account is created, its preexisting storage |
| 636 | # is ignored. |
| 637 | if address in state.created_accounts: |
| 638 | return U256(0) |
| 639 | |
| 640 | _, original_trie = state._snapshots[0] |
| 641 | original_account_trie = original_trie.get(address) |
| 642 | |
| 643 | if original_account_trie is None: |
| 644 | original_value = U256(0) |
| 645 | else: |
| 646 | original_value = trie_get(original_account_trie, key) |
| 647 | |
| 648 | assert isinstance(original_value, U256) |
| 649 | |
| 650 | return original_value |
get_transient_storage ¶
Get a value at a storage key on an account from transient storage.
Returns U256(0) if the storage key has not been set previously.
Parameters
transient_storage: TransientStorage
The transient storage
address : Address
Address of the account.
key : Bytes
Key to lookup.
Returns
value : U256
Value at the key.
def get_transient_storage(transient_storage: TransientStorage, address: Address, key: Bytes32) -> U256:
| 656 | """ |
|---|---|
| 657 | Get a value at a storage key on an account from transient storage. |
| 658 | Returns `U256(0)` if the storage key has not been set previously. |
| 659 | |
| 660 | Parameters |
| 661 | ---------- |
| 662 | transient_storage: `TransientStorage` |
| 663 | The transient storage |
| 664 | address : `Address` |
| 665 | Address of the account. |
| 666 | key : `Bytes` |
| 667 | Key to lookup. |
| 668 | |
| 669 | Returns |
| 670 | ------- |
| 671 | value : `U256` |
| 672 | Value at the key. |
| 673 | |
| 674 | """ |
| 675 | trie = transient_storage._tries.get(address) |
| 676 | if trie is None: |
| 677 | return U256(0) |
| 678 | |
| 679 | value = trie_get(trie, key) |
| 680 | |
| 681 | assert isinstance(value, U256) |
| 682 | return value |
set_transient_storage ¶
Set a value at a storage key on an account. Setting to U256(0) deletes
the key.
Parameters
transient_storage: TransientStorage
The transient storage
address : Address
Address of the account.
key : Bytes
Key to set.
value : U256
Value to set at the key.
def set_transient_storage(transient_storage: TransientStorage, address: Address, key: Bytes32, value: U256) -> None:
| 691 | """ |
|---|---|
| 692 | Set a value at a storage key on an account. Setting to `U256(0)` deletes |
| 693 | the key. |
| 694 | |
| 695 | Parameters |
| 696 | ---------- |
| 697 | transient_storage: `TransientStorage` |
| 698 | The transient storage |
| 699 | address : `Address` |
| 700 | Address of the account. |
| 701 | key : `Bytes` |
| 702 | Key to set. |
| 703 | value : `U256` |
| 704 | Value to set at the key. |
| 705 | |
| 706 | """ |
| 707 | trie = transient_storage._tries.get(address) |
| 708 | if trie is None: |
| 709 | trie = Trie(secured=True, default=U256(0)) |
| 710 | transient_storage._tries[address] = trie |
| 711 | trie_set(trie, key, value) |
| 712 | if trie._data == {}: |
| 713 | del transient_storage._tries[address] |