Merge branch 'master' into next-v5.0

scripts/generate/templates/StorageSlot.js

@@ -0,0 +1,87 @@
+const format = require('../format-lines');
+const { capitalize, unique } = require('../../helpers');
+
+const TYPES = [
+  { type: 'address', isValueType: true, version: '4.1' },
+  { type: 'bool', isValueType: true, name: 'Boolean', version: '4.1' },
+  { type: 'bytes32', isValueType: true, version: '4.1' },
+  { type: 'uint256', isValueType: true, version: '4.1' },
+  { type: 'string', isValueType: false, version: '4.9' },
+  { type: 'bytes', isValueType: false, version: '4.9' },
+].map(type => Object.assign(type, { struct: (type.name ?? capitalize(type.type)) + 'Slot' }));
+
+const VERSIONS = unique(TYPES.map(t => t.version)).map(
+  version =>
+    `_Available since v${version} for ${TYPES.filter(t => t.version == version)
+      .map(t => `\`${t.type}\``)
+      .join(', ')}._`,
+);
+
+const header = `\
+pragma solidity ^0.8.0;
+
+/**
+ * @dev Library for reading and writing primitive types to specific storage slots.
+ *
+ * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
+ * This library helps with reading and writing to such slots without the need for inline assembly.
+ *
+ * The functions in this library return Slot structs that contain a \`value\` member that can be used to read or write.
+ *
+ * Example usage to set ERC1967 implementation slot:
+ * \`\`\`solidity
+ * contract ERC1967 {
+ *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
+ *
+ *     function _getImplementation() internal view returns (address) {
+ *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
+ *     }
+ *
+ *     function _setImplementation(address newImplementation) internal {
+ *         require(newImplementation.code.length > 0, "ERC1967: new implementation is not a contract");
+ *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
+ *     }
+ * }
+ * \`\`\`
+ *
+${VERSIONS.map(s => ` * ${s}`).join('\n')}
+ */
+`;
+
+const struct = type => `\
+struct ${type.struct} {
+  ${type.type} value;
+}
+`;
+
+const get = type => `\
+/**
+ * @dev Returns an \`${type.struct}\` with member \`value\` located at \`slot\`.
+ */
+function get${type.struct}(bytes32 slot) internal pure returns (${type.struct} storage r) {
+  /// @solidity memory-safe-assembly
+  assembly {
+      r.slot := slot
+  }
+}
+`;
+
+const getStorage = type => `\
+/**
+ * @dev Returns an \`${type.struct}\` representation of the ${type.type} storage pointer \`store\`.
+ */
+function get${type.struct}(${type.type} storage store) internal pure returns (${type.struct} storage r) {
+  /// @solidity memory-safe-assembly
+  assembly {
+      r.slot := store.slot
+  }
+}
+`;
+
+// GENERATE
+module.exports = format(
+  header.trimEnd(),
+  'library StorageSlot {',
+  [...TYPES.map(struct), ...TYPES.flatMap(type => [get(type), type.isValueType ? '' : getStorage(type)])],
+  '}',
+);