From 953c83911e9024bdd97bedfbcd489145eed4eb61 Mon Sep 17 00:00:00 2001
From: Nazar Hussain <nazarhussain@gmail.com>
Date: Wed, 6 Jul 2022 13:18:53 +0200
Subject: [PATCH] :label: Fix the contract types

---
 packages/web3-eth-abi/src/types.ts            | 24 +++++++++++--------
 packages/web3-eth-contract/src/contract.ts    |  2 +-
 .../test/unit/contract_typing.test.ts         |  6 ++---
 3 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/packages/web3-eth-abi/src/types.ts b/packages/web3-eth-abi/src/types.ts
index 08a318a05ed..2b6c5141127 100644
--- a/packages/web3-eth-abi/src/types.ts
+++ b/packages/web3-eth-abi/src/types.ts
@@ -177,38 +177,42 @@ export type MatchPrimitiveType<
 	| PrimitiveTupleType<Type, Components>
 	| never;
 
-export type ContractMethodOutputParameters<Params extends Array<unknown> | undefined> =
-	Params extends []
+export type ContractMethodOutputParameters<Params extends ReadonlyArray<unknown> | undefined> =
+	Params extends readonly []
 		? []
-		: Params extends [infer H, ...infer R]
+		: Params extends readonly [infer H, ...infer R]
 		? H extends AbiParameter
 			? // TODO: Find a way to set name for tuple item
 			  [MatchPrimitiveType<H['type'], H['components']>, ...ContractMethodOutputParameters<R>]
 			: ContractMethodOutputParameters<R>
+		: Params extends undefined | unknown
+		? []
 		: Params;
 
-export type ContractMethodInputParameters<Params extends Array<unknown> | undefined> =
-	Params extends []
+export type ContractMethodInputParameters<Params extends ReadonlyArray<unknown> | undefined> =
+	Params extends readonly []
 		? []
-		: Params extends [infer H, ...infer R]
+		: Params extends readonly [infer H, ...infer R]
 		? H extends AbiParameter
 			? // TODO: Find a way to set name for tuple item
 			  [MatchPrimitiveType<H['type'], H['components']>, ...ContractMethodInputParameters<R>]
 			: ContractMethodInputParameters<R>
+		: Params extends undefined | unknown
+		? []
 		: Params;
 
 export type ContractConstructor<Abis extends ContractAbi> = {
 	[Abi in FilterAbis<Abis, AbiConstructorFragment> as 'constructor']: {
 		readonly Abi: Abi;
-		readonly Inputs: ContractMethodInputParameters<[...NonNullable<Abi['inputs']>]>;
+		readonly Inputs: ContractMethodInputParameters<Abi['inputs']>;
 	};
 }['constructor'];
 
 export type ContractMethod<Abi extends AbiFunctionFragment> = {
 	readonly Abi: Abi;
 
-	readonly Inputs?: ContractMethodInputParameters<[...NonNullable<Abi['inputs']>]>;
-	readonly Outputs?: ContractMethodOutputParameters<[...NonNullable<Abi['outputs']>]>;
+	readonly Inputs: ContractMethodInputParameters<Abi['inputs']>;
+	readonly Outputs: ContractMethodOutputParameters<Abi['outputs']>;
 };
 
 export type ContractMethods<Abis extends ContractAbi> = {
@@ -220,7 +224,7 @@ export type ContractMethods<Abis extends ContractAbi> = {
 
 export type ContractEvent<Abi extends AbiEventFragment> = {
 	readonly Abi: Abi;
-	readonly Inputs: ContractMethodInputParameters<[...NonNullable<Abi['inputs']>]>;
+	readonly Inputs: ContractMethodInputParameters<Abi['inputs']>;
 };
 
 export type ContractEvents<Abis extends ContractAbi> = {
diff --git a/packages/web3-eth-contract/src/contract.ts b/packages/web3-eth-contract/src/contract.ts
index d3f5464c41a..61db8b6a0cc 100644
--- a/packages/web3-eth-contract/src/contract.ts
+++ b/packages/web3-eth-contract/src/contract.ts
@@ -92,7 +92,7 @@ import {
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 type ContractBoundMethod<Method extends ContractMethod<any>> = (
-	...args: NonNullable<Method['Inputs']>
+	...args: Method['Inputs']
 ) => Method['Abi']['stateMutability'] extends 'payable' | 'pure'
 	? PayableMethodObject<Method['Inputs'], Method['Outputs']>
 	: NonPayableMethodObject<Method['Inputs'], Method['Outputs']>;
diff --git a/packages/web3-eth-contract/test/unit/contract_typing.test.ts b/packages/web3-eth-contract/test/unit/contract_typing.test.ts
index 781155a5f15..58b0e69dae9 100644
--- a/packages/web3-eth-contract/test/unit/contract_typing.test.ts
+++ b/packages/web3-eth-contract/test/unit/contract_typing.test.ts
@@ -30,9 +30,9 @@ describe('contract typing', () => {
 			expectTypeOf<keyof typeof contract.methods>().toBe<keyof Erc20Interface['methods']>(),
 		);
 
-		// typecheck.skip('should have interface compliance methods', () =>
-		// 	expectTypeOf(contract.methods).toExtend<Erc20Interface['methods']>(),
-		// );
+		typecheck('should have interface compliance methods', () =>
+			expectTypeOf(contract.methods).toExtend<Erc20Interface['methods']>(),
+		);
 
 		typecheck('should have all events', () =>
 			expectTypeOf<keyof typeof contract.events>().toBe<keyof Erc20Interface['events']>(),