Bump @openzeppelin/contracts from 2.4.0 to 4.2.0

[dependabot-preview]

Bumps @openzeppelin/contracts from 2.4.0 to 4.2.0.

Release notes

Sourced from @​openzeppelin/contracts's releases.

v4.2.0

Read the full announcement in the blog!

---

• ERC20Votes: add a new extension of the ERC20 token with support for voting snapshots and delegation. (#2632)
• ERC20VotesComp: Variant of ERC20Votes that is compatible with Compound's Comp token interface but restricts supply to uint96. (#2706)
• ERC20Wrapper: add a new extension of the ERC20 token which wraps an underlying token. Deposit and withdraw guarantee that the total supply is backed by a corresponding amount of underlying token. (#2633)
• Enumerables: Improve gas cost of removal in EnumerableSet and EnumerableMap.
• Enumerables: Improve gas cost of lookup in EnumerableSet and EnumerableMap.
• Counter: add a reset method. (#2678)
• Tokens: Wrap definitely safe subtractions in unchecked blocks.
• Math: Add a ceilDiv method for performing ceiling division.
• ERC1155Supply: add a new ERC1155 extension that keeps track of the totalSupply of each tokenId. (#2593)
• BitMaps: add a new BitMaps library that provides a storage efficient datastructure for uint256 to bool mapping with contiguous keys. (#2710)

Breaking Changes

• ERC20FlashMint is no longer a Draft ERC. (#2673))

How to update: Change your import paths by removing the draft- prefix from @openzeppelin/contracts/token/ERC20/extensions/draft-ERC20FlashMint.sol.

See Releases and Stability: Drafts.

v4.1.0

Read the full announcement in the blog or check out the changelog.

• IERC20Metadata: add a new extended interface that includes the optional name(), symbol() and decimals() functions. (#2561)
• ERC777: make reception acquirement optional in _mint. (#2552)
• ERC20Permit: add a _useNonce to enable further usage of ERC712 signatures. (#2565)
• ERC20FlashMint: add an implementation of the ERC3156 extension for flash-minting ERC20 tokens. (#2543)
• SignatureChecker: add a signature verification library that supports both EOA and ERC1271 compliant contracts as signers. (#2532)
• Multicall: add abstract contract with multicall(bytes[] calldata data) function to bundle multiple calls together (#2608)
• ECDSA: add support for ERC2098 short-signatures. (#2582)
• AccessControl: add a onlyRole modifier to restrict specific function to callers bearing a specific role. (#2609)
• StorageSlot: add a library for reading and writing primitive types to specific storage slots. (#2542)
• UUPS Proxies: add UUPSUpgradeable to implement the UUPS proxy pattern together with EIP1967Proxy. (#2542)

v4.0.0

Read the full announcement in the blog or check out the changelog.

Changelog

• Now targeting the 0.8.x line of Solidity compilers. For 0.6.x (resp 0.7.x) support, use version 3.4.0 (resp 3.4.0-solc-0.7) of OpenZeppelin.
• Context: making _msgData return bytes calldata instead of bytes memory (#2492)
• ERC20: removed the _setDecimals function and the storage slot associated to decimals. (#2502)
• Strings: addition of a toHexString function. (#2504)
• EnumerableMap: change implementation to optimize for key → value lookups instead of enumeration. (#2518)
• GSN: deprecate GSNv1 support in favor of upcoming support for GSNv2. (#2521)
• ERC165: remove uses of storage in the base ERC165 implementation. ERC165 based contracts now use storage-less virtual functions. Old behavior remains available in the ERC165Storage extension. (#2505)

... (truncated)

Changelog

Sourced from @​openzeppelin/contracts's changelog.

4.2.0 (2021-06-30)

• ERC20Votes: add a new extension of the ERC20 token with support for voting snapshots and delegation. (#2632)
• ERC20VotesComp: Variant of ERC20Votes that is compatible with Compound's Comp token interface but restricts supply to uint96. (#2706)
• ERC20Wrapper: add a new extension of the ERC20 token which wraps an underlying token. Deposit and withdraw guarantee that the total supply is backed by a corresponding amount of underlying token. (#2633)
• Enumerables: Improve gas cost of removal in EnumerableSet and EnumerableMap.
• Enumerables: Improve gas cost of lookup in EnumerableSet and EnumerableMap.
• Counter: add a reset method. (#2678)
• Tokens: Wrap definitely safe subtractions in unchecked blocks.
• Math: Add a ceilDiv method for performing ceiling division.
• ERC1155Supply: add a new ERC1155 extension that keeps track of the totalSupply of each tokenId. (#2593)
• BitMaps: add a new BitMaps library that provides a storage efficient datastructure for uint256 to bool mapping with contiguous keys. (#2710)

Breaking Changes

• ERC20FlashMint is no longer a Draft ERC. (#2673))

How to update: Change your import paths by removing the draft- prefix from @openzeppelin/contracts/token/ERC20/extensions/draft-ERC20FlashMint.sol.

See Releases and Stability: Drafts.

4.1.0 (2021-04-29)

• IERC20Metadata: add a new extended interface that includes the optional name(), symbol() and decimals() functions. (#2561)
• ERC777: make reception acquirement optional in _mint. (#2552)
• ERC20Permit: add a _useNonce to enable further usage of ERC712 signatures. (#2565)
• ERC20FlashMint: add an implementation of the ERC3156 extension for flash-minting ERC20 tokens. (#2543)
• SignatureChecker: add a signature verification library that supports both EOA and ERC1271 compliant contracts as signers. (#2532)
• Multicall: add abstract contract with multicall(bytes[] calldata data) function to bundle multiple calls together (#2608)
• ECDSA: add support for ERC2098 short-signatures. (#2582)
• AccessControl: add a onlyRole modifier to restrict specific function to callers bearing a specific role. (#2609)
• StorageSlot: add a library for reading and writing primitive types to specific storage slots. (#2542)
• UUPS Proxies: add UUPSUpgradeable to implement the UUPS proxy pattern together with EIP1967Proxy. (#2542)

Breaking changes

This release includes two small breaking changes in TimelockController.

1. The onlyRole modifier in this contract was designed to let anyone through if the role was granted to address(0), allowing the possibility to to make a role "open", which can be used for EXECUTOR_ROLE. This modifier is now replaced by AccessControl.onlyRole, which does not have this ability. The previous behavior was moved to the modifier TimelockController.onlyRoleOrOpenRole.
2. It was possible to make PROPOSER_ROLE an open role (as described in the previous item) if it was granted to address(0). This would affect the schedule, scheduleBatch, and cancel operations in TimelockController. This ability was removed as it does not make sense to open up the PROPOSER_ROLE in the same way that it does for EXECUTOR_ROLE.

4.0.0 (2021-03-23)

• Now targeting the 0.8.x line of Solidity compilers. For 0.6.x (resp 0.7.x) support, use version 3.4.0 (resp 3.4.0-solc-0.7) of OpenZeppelin.

... (truncated)

Commits

• 9fbc1d7 4.2.0
• 556e366 4.2.0-rc.0
• 6842518 Wrapper extension for ERC20 token (#2633)
• 8a775cd Emit DelegateVotesChanged events after Transfer (#2733)
• 4d0f8c1 Check inheritance tree consistency (#2727)
• 27e0900 Reorder state changes and event emission for consistency (#2719)
• 00128bd Fix function ordering in ERC1967Upgrades (#2722)
• f710baf Fix typos (#2723)
• 788d338 Improve naming of internal variables (#2721)
• 6f50f6e Remove repeated code from ERC1967Upgrade (#2720)
• Additional commits viewable in compare view

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