import { AbiDefinition, AbiType, ConstructorAbi, ContractAbi, DataItem, MethodAbi } from '@0xproject/types';
import * as _ from 'lodash';
export const abiUtils = {
parseFunctionParam(param: DataItem): string {
if (param.type === 'tuple') {
// Parse out tuple types into {type_1, type_2, ..., type_N}
const tupleComponents = param.components;
const paramString = _.map(tupleComponents, component => this.parseFunctionParam(component));
const tupleParamString = `{${paramString}}`;
return tupleParamString;
}
return param.type;
},
getFunctionSignature(methodAbi: MethodAbi): string {
const functionName = methodAbi.name;
const parameterTypeList = _.map(methodAbi.inputs, (param: DataItem) => this.parseFunctionParam(param));
const functionSignature = `${functionName}(${parameterTypeList})`;
return functionSignature;
},
/**
* Solidity supports function overloading whereas TypeScript does not.
* See: https://solidity.readthedocs.io/en/v0.4.21/contracts.html?highlight=overload#function-overloading
* In order to support overloaded functions, we suffix overloaded function names with an index.
* This index should be deterministic, regardless of function ordering within the smart contract. To do so,
* we assign indexes based on the alphabetical order of function signatures.
*
* E.g
* ['f(uint)', 'f(uint,byte32)']
* Should always be renamed to:
* ['f1(uint)', 'f2(uint,byte32)']
* Regardless of the order in which these these overloaded functions are declared within the contract ABI.
*/
renameOverloadedMethods(inputContractAbi: ContractAbi): ContractAbi {
const contractAbi = _.cloneDeep(inputContractAbi);
const methodAbis = contractAbi.filter((abi: AbiDefinition) => abi.type === AbiType.Function) as MethodAbi[];
// Sort method Abis into alphabetical order, by function signature
const methodAbisOrdered = _.sortBy(methodAbis, [
(methodAbi: MethodAbi) => {
const functionSignature = this.getFunctionSignature(methodAbi);
return functionSignature;
},
]);
// Group method Abis by name (overloaded methods will be grouped together, in alphabetical order)
const methodAbisByName: { [key: string]: MethodAbi[] } = {};
_.each(methodAbisOrdered, methodAbi => {
(methodAbisByName[methodAbi.name] || (methodAbisByName[methodAbi.name] = [])).push(methodAbi);
});
// Rename overloaded methods to overloadedMethodName1, overloadedMethodName2, ...
_.each(methodAbisByName, methodAbisWithSameName => {
_.each(methodAbisWithSameName, (methodAbi, i: number) => {
if (methodAbisWithSameName.length > 1) {
const overloadedMethodId = i + 1;
const sanitizedMethodName = `${methodAbi.name}${overloadedMethodId}`;
const indexOfExistingAbiWithSanitizedMethodNameIfExists = _.findIndex(
methodAbis,
currentMethodAbi => currentMethodAbi.name === sanitizedMethodName,
);
if (indexOfExistingAbiWithSanitizedMethodNameIfExists >= 0) {
const methodName = methodAbi.name;
throw new Error(
`Failed to rename overloaded method '${methodName}' to '${sanitizedMethodName}'. A method with this name already exists.`,
);
}
methodAbi.name = sanitizedMethodName;
}
});
});
return contractAbi;
},
};