Further reorganisation of the repo (#2575)

Co-authored-by: Francisco Giordano <frangio.1@gmail.com>
(cherry picked from commit f076ff5d)

CHANGELOG.md

@@ -34,6 +34,10 @@ 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 during the beta the 4.0-beta.x phase. Transitions made during this period are also configured in the `migrate-imports` script. Consequently, you can upgrade from the 4.0-beta.x stage 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/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

+= 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

 = 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/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/utils/README.adoc

@@ -40,6 +40,14 @@ Finally, {Create2} contains all necessary utilities to safely use the https://bl
 
 {{EIP712}}
 
+== Escrow
+
+{{ConditionalEscrow}}
+
+{{Escrow}}
+
+{{RefundEscrow}}
+
 == Introspection
 
 This set of interfaces and contracts deal with https://en.wikipedia.org/wiki/Type_introspection[type introspection] of contracts, that is, examining which functions can be called on them. This is usually referred to as a contract's _interface_.
@@ -84,7 +92,3 @@ Note that, in all cases, accounts simply _declare_ their interfaces, but they ar
 {{Counters}}
 
 {{Strings}}
-
-== Other
-
-{{Initializable}}

scripts/migrate-imports.js

@@ -30,7 +30,8 @@ const pathUpdates = {
   'payment/escrow/ConditionalEscrow.sol': 'utils/escrow/ConditionalEscrow.sol',
   'payment/escrow/Escrow.sol': 'utils/escrow/Escrow.sol',
   'payment/escrow/RefundEscrow.sol': 'utils/escrow/RefundEscrow.sol',
-  'payment/PaymentSplitter.sol': 'utils/PaymentSplitter.sol',
+  'payment/PaymentSplitter.sol': 'finance/PaymentSplitter.sol',
+  'utils/PaymentSplitter.sol': 'finance/PaymentSplitter.sol',
   'payment/PullPayment.sol': 'security/PullPayment.sol',
   'presets/ERC1155PresetMinterPauser.sol': 'token/ERC1155/presets/ERC1155PresetMinterPauser.sol',
   'presets/ERC20PresetFixedSupply.sol': 'token/ERC20/presets/ERC20PresetFixedSupply.sol',
@@ -40,7 +41,8 @@ const pathUpdates = {
   'proxy/BeaconProxy.sol': 'proxy/beacon/BeaconProxy.sol',
   // 'proxy/Clones.sol': undefined,
   'proxy/IBeacon.sol': 'proxy/beacon/IBeacon.sol',
-  'proxy/Initializable.sol': 'utils/Initializable.sol',
+  'proxy/Initializable.sol': 'proxy/utils/Initializable.sol',
+  'utils/Initializable.sol': 'proxy/utils/Initializable.sol',
   'proxy/ProxyAdmin.sol': 'proxy/transparent/ProxyAdmin.sol',
   // 'proxy/Proxy.sol': undefined,
   'proxy/TransparentUpgradeableProxy.sol': 'proxy/transparent/TransparentUpgradeableProxy.sol',