Solidity API

LibDiamond

A library for implementing the Diamond pattern (EIP-2535)

This library provides core functionality for diamond proxies, including facet management and function selector handling

InValidFacetCutAction

error InValidFacetCutAction()

Error thrown when an invalid facet cut action is provided

NotDiamondOwner

error NotDiamondOwner()

Error thrown when the caller is not the diamond owner

NoSelectorsInFacet

error NoSelectorsInFacet()

Error thrown when no selectors are provided for a facet

NoZeroAddress

error NoZeroAddress()

Error thrown when the zero address is used

SelectorExists

error SelectorExists(bytes4 selector)

Error thrown when a selector already exists

Parameters

Name	Type	Description
selector	bytes4	The existing selector

SameSelectorReplacement

error SameSelectorReplacement(bytes4 selector)

Error thrown when attempting to replace a selector with the same selector

Parameters

Name	Type	Description
selector	bytes4	The selector being replaced

MustBeZeroAddress

error MustBeZeroAddress()

Error thrown when a non-zero address is expected

NoCode

error NoCode()

Error thrown when a contract has no code

NonExistentSelector

error NonExistentSelector(bytes4 selector)

Error thrown when a non-existent selector is used

Parameters

Name	Type	Description
selector	bytes4	The non-existent selector

ImmutableFunction

error ImmutableFunction(bytes4 selector)

Error thrown when attempting to modify an immutable function

Parameters

Name	Type	Description
selector	bytes4	The selector of the immutable function

NonEmptyCalldata

error NonEmptyCalldata()

Error thrown when calldata is expected to be empty

EmptyCalldata

error EmptyCalldata()

Error thrown when calldata is expected to be non-empty

InitCallFailed

error InitCallFailed()

Error thrown when an initialization call fails

DIAMOND_STORAGE_POSITION

bytes32 DIAMOND_STORAGE_POSITION

Unique storage position for diamond storage

FacetAddressAndPosition

Struct to store facet address and function selector position

Parameters

Name	Type	Description

struct FacetAddressAndPosition {
  address facetAddress;
  uint96 functionSelectorPosition;
}

FacetFunctionSelectors

Struct to store function selectors for a facet

Parameters

Name	Type	Description

struct FacetFunctionSelectors {
  bytes4[] functionSelectors;
  uint256 facetAddressPosition;
}

DiamondStorage

Main storage struct for the diamond

Stores all necessary information for the diamond proxy

struct DiamondStorage {
  mapping(bytes4 => struct LibDiamond.FacetAddressAndPosition) selectorToFacetAndPosition;
  mapping(address => struct LibDiamond.FacetFunctionSelectors) facetFunctionSelectors;
  address[] facetAddresses;
  mapping(bytes4 => bool) supportedInterfaces;
  mapping(string => bool) supportedFunctionInterfaces;
  address contractOwner;
  address diamondAddress;
}

diamondStorage

function diamondStorage() internal pure returns (struct LibDiamond.DiamondStorage ds)

Retrieves the diamond storage

Return Values

Name	Type	Description
ds	struct LibDiamond.DiamondStorage	The DiamondStorage struct

OwnershipTransferred

event OwnershipTransferred(address previousOwner, address newOwner)

Emitted when contract ownership is transferred

Parameters

Name	Type	Description
previousOwner	address	Address of the previous owner
newOwner	address	Address of the new owner

setContractOwner

function setContractOwner(address _newOwner) internal

Sets a new contract owner

Parameters

Name	Type	Description
_newOwner	address	Address of the new owner

contractOwner

function contractOwner() internal view returns (address contractOwner_)

Retrieves the current contract owner

Return Values

Name	Type	Description
contractOwner_	address	Address of the current contract owner

enforceIsContractOwner

function enforceIsContractOwner() internal view

Ensures that the caller is the contract owner

Reverts if the caller is not the contract owner

diamondCut

function diamondCut(struct IDiamondCut.FacetCut[] _diamondCut, struct IPropsInitCall.InitCall[] _initCalls) internal

Internal function to perform a diamond cut

Parameters

Name	Type	Description
_diamondCut	struct IDiamondCut.FacetCut[]	Array of FacetCut structs describing the changes
_initCalls	struct IPropsInitCall.InitCall[]	Array of InitCall structs for initialization

executeExternalInitCalls

function executeExternalInitCalls(address _diamond, struct IPropsInitCall.InitCall[] _externalInitCalls) internal

modifySupportedInterfaces

function modifySupportedInterfaces(bytes4[] _addInterfaceIds, bytes4[] _removeInterfaceIds) internal

Modifies the supported interfaces

Parameters

Name	Type	Description
_addInterfaceIds	bytes4[]	Array of interface IDs to add
_removeInterfaceIds	bytes4[]	Array of interface IDs to remove

modifySupportedFunctionInterfaces

function modifySupportedFunctionInterfaces(string[] _addInterfaceIds, string[] _removeInterfaceIds) internal

Modifies the supported function interfaces

Parameters

Name	Type	Description
_addInterfaceIds	string[]	Array of function interface IDs to add
_removeInterfaceIds	string[]	Array of function interface IDs to remove

addFunctions

function addFunctions(address _facetAddress, bytes4[] _functionSelectors) internal

Adds new functions to a facet

Parameters

Name	Type	Description
_facetAddress	address	Address of the facet
_functionSelectors	bytes4[]	Array of function selectors to add

replaceFunctions

function replaceFunctions(address _facetAddress, bytes4[] _functionSelectors) internal

Replaces functions in a facet

Parameters

Name	Type	Description
_facetAddress	address	Address of the facet
_functionSelectors	bytes4[]	Array of function selectors to replace

removeFunctions

function removeFunctions(address _facetAddress, bytes4[] _functionSelectors) internal

Removes functions from a facet

Parameters

Name	Type	Description
_facetAddress	address	Address of the facet (should be zero address)
_functionSelectors	bytes4[]	Array of function selectors to remove

addFacet

function addFacet(struct LibDiamond.DiamondStorage ds, address _facetAddress) internal

Adds a new facet to the diamond

Parameters

Name	Type	Description
ds	struct LibDiamond.DiamondStorage	DiamondStorage struct
_facetAddress	address	Address of the new facet

addFunction

function addFunction(struct LibDiamond.DiamondStorage ds, bytes4 _selector, uint96 _selectorPosition, address _facetAddress) internal

Adds a function to a facet

Parameters

Name	Type	Description
ds	struct LibDiamond.DiamondStorage	DiamondStorage struct
_selector	bytes4	Function selector to add
_selectorPosition	uint96	Position of the selector in the functionSelectors array
_facetAddress	address	Address of the facet

removeFunction

function removeFunction(struct LibDiamond.DiamondStorage ds, address _facetAddress, bytes4 _selector) internal

Removes a function from a facet

Parameters

Name	Type	Description
ds	struct LibDiamond.DiamondStorage	DiamondStorage struct
_facetAddress	address	Address of the facet
_selector	bytes4	Function selector to remove

initializeDiamondCut

function initializeDiamondCut(struct IPropsInitCall.InitCall[] _initCalls) internal

Initializes the diamond cut

Parameters

Name	Type	Description
_initCalls	struct IPropsInitCall.InitCall[]	Array of InitCall structs for initialization

bytesToHex

function bytesToHex(bytes data) internal pure returns (string)

Converts bytes to a hexadecimal string

Parameters

Name	Type	Description
data	bytes	Bytes to convert

Return Values

Name	Type	Description
[0]	string	Hexadecimal string representation of the input bytes

enforceHasContractCode

function enforceHasContractCode(address _contract) internal view

Ensures that a contract has code

Parameters

Name	Type	Description
_contract	address	Address of the contract to check

createFunctionIdentifier

function createFunctionIdentifier(address _facetAddress, bytes4 _selector) internal pure returns (string)

Creates a unique function identifier

Parameters

Name	Type	Description
_facetAddress	address	Address of the facet
_selector	bytes4	Function selector

Return Values

Name	Type	Description
[0]	string	Unique function identifier string

addressToString

function addressToString(address _addr) internal pure returns (string)

Converts an address to a string

Parameters

Name	Type	Description
_addr	address	Address to convert

Return Values

Name	Type	Description
[0]	string	String representation of the address

bytes4ToHexString

function bytes4ToHexString(bytes4 _bytes) internal pure returns (string)

Converts bytes4 to a hexadecimal string

Parameters

Name	Type	Description
_bytes	bytes4	Bytes4 to convert

Return Values

Name	Type	Description
[0]	string	Hexadecimal string representation of the bytes4

toHexString

function toHexString(uint256 value, uint256 length) internal pure returns (string)

Converts a uint256 value to a hexadecimal string of specified length

Parameters

Name	Type	Description
value	uint256	The uint256 value to convert
length	uint256	The desired length of the output string

Return Values

Name	Type	Description
[0]	string	Hexadecimal string representation of the input value