Merge branch 'master' into feature/ERC3156

CHANGELOG.md

@@ -1,23 +1,35 @@
 # Changelog
 
+## Unreleased
+
+ * `IERC20Metadata`: add a new extended interface that includes the optional `name()`, `symbol()` and `decimals()` functions. ([#2561](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2561))
+ * `ERC777`: make reception acquirement optional in `_mint`. ([#2552](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2552))
+
 ## Unreleased
 
  * 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](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2492))
- * `ERC20`: Removed the `_setDecimals` function and the storage slot associated to decimals. ([#2502](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2502))
+ * `ERC20`: removed the `_setDecimals` function and the storage slot associated to decimals. ([#2502](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2502))
  * `Strings`: addition of a `toHexString` function.  ([#2504](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2504))
  * `EnumerableMap`: change implementation to optimize for `key → value` lookups instead of enumeration. ([#2518](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2518))
- * `GSN`: Deprecate GSNv1 support in favor of upcomming support for GSNv2. ([#2521](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2521))
- * `ERC165`: Remove uses of storage in the base ERC165 implementation. ERC165 based contracts now use storage-less virtual functions. Old behaviour remains available in the `ERC165Storage` extension. ([#2505](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2505))
- * `Initializable`: Make initializer check stricter during construction. ([#2531](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2531))
+ * `GSN`: deprecate GSNv1 support in favor of upcoming support for GSNv2. ([#2521](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/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](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2505))
+ * `Initializable`: make initializer check stricter during construction. ([#2531](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2531))
  * `ERC721`: remove enumerability of tokens from the base implementation. This feature is now provided separately through the `ERC721Enumerable` extension. ([#2511](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2511))
  * `AccessControl`: removed enumerability by default for a more lightweight contract. It is now opt-in through `AccessControlEnumerable`. ([#2512](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2512))
  * Meta Transactions: add `ERC2771Context` and a `MinimalForwarder` for meta-transactions. ([#2508](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2508))
- * Overall reorganisation of the contract folder to improve clarity and discoverability. ([#2503](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2503))
- * `ERC20Capped`: optimize gas usage of by enforcing te check directly in `_mint`. ([#2524](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2524))
+ * Overall reorganization of the contract folder to improve clarity and discoverability. ([#2503](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2503))
+ * `ERC20Capped`: optimize gas usage by enforcing the check directly in `_mint`. ([#2524](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2524))
  * Rename `UpgradeableProxy` to `ERC1967Proxy`. ([#2547](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2547))
- * `ERC777`: Optimize the gas costs of the constructor. ([#2551](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2551))
- * `ERC721URIStorage`: Add a new extension that implements the `_setTokenURI` behavior as it was available in 3.4.0. ([#2555](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2555))
+ * `ERC777`: optimize the gas costs of the constructor. ([#2551](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2551))
+ * `ERC721URIStorage`: add a new extension that implements the `_setTokenURI` behavior as it was available in 3.4.0. ([#2555](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2555))
+ * `AccessControl`: added ERC165 interface detection. ([#2562](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2562))
+ * `ERC1155`: make `uri` public so overloading function can call it using super. ([#2576](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2576))
+
+### Bug fixes for beta releases
+
+ * `AccessControlEnumerable`: Fixed `renounceRole` not updating enumerable set of addresses for a role. ([#2572](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2572))
+
 
 ### How to upgrade from 3.x
 
@@ -29,6 +41,10 @@ npx openzeppelin-contracts-migrate-imports
 
 Make sure you're using git or another version control system to be able to recover from any potential error in our script.
 
+### How to upgrade from 4.0-beta.x
+
+Some further changes have been done between the different beta iterations. Transitions made during this period are configured in the `migrate-imports` script. Consequently, you can upgrade from any previous 4.0-beta.x version using the same script as described in the *How to upgrade from 3.x* section.
+
 ## 3.4.0 (2021-02-02)
 
  * `BeaconProxy`: added new kind of proxy that allows simultaneous atomic upgrades. ([#2411](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2411))

contracts/access/AccessControl.sol

@@ -3,6 +3,18 @@
 pragma solidity ^0.8.0;
 
 import "../utils/Context.sol";
+import "../utils/introspection/ERC165.sol";
+
+/**
+ * @dev External interface of AccessControl declared to support ERC165 detection.
+ */
+interface IAccessControl {
+    function hasRole(bytes32 role, address account) external view returns (bool);
+    function getRoleAdmin(bytes32 role) external view returns (bytes32);
+    function grantRole(bytes32 role, address account) external;
+    function revokeRole(bytes32 role, address account) external;
+    function renounceRole(bytes32 role, address account) external;
+}
 
 /**
  * @dev Contract module that allows children to implement role-based access
@@ -42,7 +54,7 @@ import "../utils/Context.sol";
  * grant and revoke this role. Extra precautions should be taken to secure
  * accounts that have been granted it.
  */
-abstract contract AccessControl is Context {
+abstract contract AccessControl is Context, IAccessControl, ERC165 {
     struct RoleData {
         mapping (address => bool) members;
         bytes32 adminRole;
@@ -79,10 +91,18 @@ abstract contract AccessControl is Context {
      */
     event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
 
+    /**
+     * @dev See {IERC165-supportsInterface}.
+     */
+    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
+        return interfaceId == type(IAccessControl).interfaceId
+            || super.supportsInterface(interfaceId);
+    }
+
     /**
      * @dev Returns `true` if `account` has been granted `role`.
      */
-    function hasRole(bytes32 role, address account) public view returns (bool) {
+    function hasRole(bytes32 role, address account) public view override returns (bool) {
         return _roles[role].members[account];
     }
 
@@ -92,7 +112,7 @@ abstract contract AccessControl is Context {
      *
      * To change a role's admin, use {_setRoleAdmin}.
      */
-    function getRoleAdmin(bytes32 role) public view returns (bytes32) {
+    function getRoleAdmin(bytes32 role) public view override returns (bytes32) {
         return _roles[role].adminRole;
     }
 
@@ -106,7 +126,7 @@ abstract contract AccessControl is Context {
      *
      * - the caller must have ``role``'s admin role.
      */
-    function grantRole(bytes32 role, address account) public virtual {
+    function grantRole(bytes32 role, address account) public virtual override {
         require(hasRole(getRoleAdmin(role), _msgSender()), "AccessControl: sender must be an admin to grant");
 
         _grantRole(role, account);
@@ -121,7 +141,7 @@ abstract contract AccessControl is Context {
      *
      * - the caller must have ``role``'s admin role.
      */
-    function revokeRole(bytes32 role, address account) public virtual {
+    function revokeRole(bytes32 role, address account) public virtual override {
         require(hasRole(getRoleAdmin(role), _msgSender()), "AccessControl: sender must be an admin to revoke");
 
         _revokeRole(role, account);
@@ -141,7 +161,7 @@ abstract contract AccessControl is Context {
      *
      * - the caller must be `account`.
      */
-    function renounceRole(bytes32 role, address account) public virtual {
+    function renounceRole(bytes32 role, address account) public virtual override {
         require(account == _msgSender(), "AccessControl: can only renounce roles for self");
 
         _revokeRole(role, account);

contracts/access/AccessControlEnumerable.sol

@@ -5,14 +5,30 @@ pragma solidity ^0.8.0;
 import "./AccessControl.sol";
 import "../utils/structs/EnumerableSet.sol";
 
+/**
+ * @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
+ */
+interface IAccessControlEnumerable {
+    function getRoleMember(bytes32 role, uint256 index) external view returns (address);
+    function getRoleMemberCount(bytes32 role) external view returns (uint256);
+}
+
 /**
  * @dev Extension of {AccessControl} that allows enumerating the members of each role.
  */
-abstract contract AccessControlEnumerable is AccessControl {
+abstract contract AccessControlEnumerable is IAccessControlEnumerable, AccessControl {
     using EnumerableSet for EnumerableSet.AddressSet;
 
     mapping (bytes32 => EnumerableSet.AddressSet) private _roleMembers;
 
+    /**
+     * @dev See {IERC165-supportsInterface}.
+     */
+    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
+        return interfaceId == type(IAccessControlEnumerable).interfaceId
+            || super.supportsInterface(interfaceId);
+    }
+
     /**
      * @dev Returns one of the accounts that have `role`. `index` must be a
      * value between 0 and {getRoleMemberCount}, non-inclusive.
@@ -25,15 +41,15 @@ abstract contract AccessControlEnumerable is AccessControl {
      * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
      * for more information.
      */
-    function getRoleMember(bytes32 role, uint256 index) public view returns (address) {
+    function getRoleMember(bytes32 role, uint256 index) public view override returns (address) {
         return _roleMembers[role].at(index);
     }
 
     /**
      * @dev Returns the number of accounts that have `role`. Can be used
      * together with {getRoleMember} to enumerate all bearers of a role.
      */
-    function getRoleMemberCount(bytes32 role) public view returns (uint256) {
+    function getRoleMemberCount(bytes32 role) public view override returns (uint256) {
         return _roleMembers[role].length();
     }
 
@@ -53,6 +69,14 @@ abstract contract AccessControlEnumerable is AccessControl {
         _roleMembers[role].remove(account);
     }
 
+    /**
+     * @dev Overload {renounceRole} to track enumerable memberships
+     */
+    function renounceRole(bytes32 role, address account) public virtual override {
+        super.renounceRole(role, account);
+        _roleMembers[role].remove(account);
+    }
+
     /**
      * @dev Overload {_setupRole} to track enumerable memberships
      */

contracts/utils/PaymentSplitter.sol → contracts/finance/PaymentSplitter.sol

@@ -2,9 +2,9 @@
 
 pragma solidity ^0.8.0;
 
-import "./Address.sol";
-import "./Context.sol";
-import "./math/SafeMath.sol";
+import "../utils/Address.sol";
+import "../utils/Context.sol";
+import "../utils/math/SafeMath.sol";
 
 /**
  * @title PaymentSplitter

contracts/finance/README.adoc

@@ -0,0 +1,10 @@
+= Finance
+
+[.readme-notice]
+NOTE: This document is better viewed at https://docs.openzeppelin.com/contracts/api/finance
+
+This directory includes primitives for financial systems. We currently only offer the {PaymentSplitter} contract, but we want to grow this directory so we welcome ideas.
+
+== PaymentSplitter
+
+{{PaymentSplitter}}

contracts/governance/README.adoc

@@ -1,7 +1,7 @@
 = Governance
 
 [.readme-notice]
-NOTE: This document is better viewed at https://docs.openzeppelin.com/contracts/api/access
+NOTE: This document is better viewed at https://docs.openzeppelin.com/contracts/api/governance
 
 This directory includes primitives for on-chain governance. We currently only offer the {TimelockController} contract, that can be used as a component in a governance systems to introduce a delay between a proposal and its execution.
 

contracts/mocks/ERC777Mock.sol

@@ -27,6 +27,16 @@ contract ERC777Mock is Context, ERC777 {
         _mint(to, amount, userData, operatorData);
     }
 
+    function mintInternalExtended (
+        address to,
+        uint256 amount,
+        bytes memory userData,
+        bytes memory operatorData,
+        bool requireReceptionAck
+    ) public {
+        _mint(to, amount, userData, operatorData, requireReceptionAck);
+    }
+
     function approveInternal(address holder, address spender, uint256 value) public {
         _approve(holder, spender, value);
     }

contracts/mocks/InitializableMock.sol

@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.0;
 
-import "../utils/Initializable.sol";
+import "../proxy/utils/Initializable.sol";
 
 /**
  * @title InitializableMock

contracts/mocks/MultipleInheritanceInitializableMocks.sol

@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.0;
 
-import "../utils/Initializable.sol";
+import "../proxy/utils/Initializable.sol";
 
 // Sample contracts showing upgradeability with multiple inheritance.
 // Child contract inherits from Father and Mother contracts, and Father extends from Gramps.

contracts/mocks/RegressionImplementation.sol

@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.0;
 
-import "../utils/Initializable.sol";
+import "../proxy/utils/Initializable.sol";
 
 contract Implementation1 is Initializable {
   uint internal _value;

contracts/mocks/SingleInheritanceInitializableMocks.sol

@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.0;
 
-import "../utils/Initializable.sol";
+import "../proxy/utils/Initializable.sol";
 
 /**
  * @title MigratableMockV1

contracts/proxy/README.adoc

@@ -40,3 +40,7 @@ CAUTION: Using upgradeable proxies correctly and securely is a difficult task th
 == Minimal Clones
 
 {{Clones}}
+
+== Utils
+
+{{Initializable}}

contracts/utils/Initializable.sol → contracts/proxy/utils/Initializable.sol

@@ -3,7 +3,7 @@
 // solhint-disable-next-line compiler-version
 pragma solidity ^0.8.0;
 
-import "./Address.sol";
+import "../../utils/Address.sol";
 
 /**
  * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed

contracts/token/ERC1155/ERC1155.sol

@@ -55,7 +55,7 @@ contract ERC1155 is Context, ERC165, IERC1155, IERC1155MetadataURI {
      * Clients calling this function must replace the `\{id\}` substring with the
      * actual token type ID.
      */
-    function uri(uint256) external view virtual override returns (string memory) {
+    function uri(uint256) public view virtual override returns (string memory) {
         return _uri;
     }
 

contracts/token/ERC1155/presets/ERC1155PresetMinterPauser.sol

@@ -89,6 +89,13 @@ contract ERC1155PresetMinterPauser is Context, AccessControlEnumerable, ERC1155B
         _unpause();
     }
 
+    /**
+     * @dev See {IERC165-supportsInterface}.
+     */
+    function supportsInterface(bytes4 interfaceId) public view virtual override(AccessControlEnumerable, ERC1155) returns (bool) {
+        return super.supportsInterface(interfaceId);
+    }
+
     function _beforeTokenTransfer(
         address operator,
         address from,

contracts/token/ERC20/ERC20.sol

@@ -3,6 +3,7 @@
 pragma solidity ^0.8.0;
 
 import "./IERC20.sol";
+import "./extensions/IERC20Metadata.sol";
 import "../../utils/Context.sol";
 
 /**
@@ -29,7 +30,7 @@ import "../../utils/Context.sol";
  * functions have been added to mitigate the well-known issues around setting
  * allowances. See {IERC20-approve}.
  */
-contract ERC20 is Context, IERC20 {
+contract ERC20 is Context, IERC20, IERC20Metadata {
     mapping (address => uint256) private _balances;
 
     mapping (address => mapping (address => uint256)) private _allowances;
@@ -56,15 +57,15 @@ contract ERC20 is Context, IERC20 {
     /**
      * @dev Returns the name of the token.
      */
-    function name() public view virtual returns (string memory) {
+    function name() public view virtual override returns (string memory) {
         return _name;
     }
 
     /**
      * @dev Returns the symbol of the token, usually a shorter version of the
      * name.
      */
-    function symbol() public view virtual returns (string memory) {
+    function symbol() public view virtual override returns (string memory) {
         return _symbol;
     }
 
@@ -81,7 +82,7 @@ contract ERC20 is Context, IERC20 {
      * no way affects any of the arithmetic of the contract, including
      * {IERC20-balanceOf} and {IERC20-transfer}.
      */
-    function decimals() public view virtual returns (uint8) {
+    function decimals() public view virtual override returns (uint8) {
         return 18;
     }
 

contracts/token/ERC20/README.adoc

@@ -10,6 +10,7 @@ TIP: For an overview of ERC20 tokens and a walk through on how to create a token
 There a few core contracts that implement the behavior specified in the EIP:
 
 * {IERC20}: the interface all ERC20 implementations should conform to.
+* {IERC20Metadata}: the extended ERC20 interface including the <<ERC20-name,`name`>>, <<ERC20-symbol,`symbol`>> and <<ERC20-decimals,`decimals`>> functions.
 * {ERC20}: the implementation of the ERC20 interface, including the <<ERC20-name,`name`>>, <<ERC20-symbol,`symbol`>> and <<ERC20-decimals,`decimals`>> optional standard extension to the base interface.
 
 Additionally there are multiple custom extensions, including:
@@ -36,6 +37,8 @@ NOTE: This core set of contracts is designed to be unopinionated, allowing devel
 
 {{IERC20}}
 
+{{IERC20Metadata}}
+
 {{ERC20}}
 
 == Extensions