Allow users to specify the contracts backend in abi-gen

1 files changed, 13 insertions, 5 deletions

diff --git a/packages/abi-gen/src/utils.ts b/packages/abi-gen/src/utils.ts
index 14255643a..dc2c5390e 100644
--- a/packages/abi-gen/src/utils.ts
+++ b/packages/abi-gen/src/utils.ts
@@ -3,14 +3,14 @@ import * as _ from 'lodash';
 import * as path from 'path';
 import * as Web3 from 'web3';
 
-import { AbiType, ParamKind } from './types';
+import { AbiType, ContractsBackend, ParamKind } from './types';
 
 export const utils = {
-    solTypeToTsType(paramKind: ParamKind, solType: string): string {
+    solTypeToTsType(paramKind: ParamKind, backend: ContractsBackend, solType: string): string {
         const trailingArrayRegex = /\[\d*\]$/;
         if (solType.match(trailingArrayRegex)) {
             const arrayItemSolType = solType.replace(trailingArrayRegex, '');
-            const arrayItemTsType = utils.solTypeToTsType(paramKind, arrayItemSolType);
+            const arrayItemTsType = utils.solTypeToTsType(paramKind, backend, arrayItemSolType);
             const arrayTsType = utils.isUnionType(arrayItemTsType)
                 ? `Array<${arrayItemTsType}>`
                 : `${arrayItemTsType}[]`;
@@ -24,13 +24,21 @@ export const utils = {
                 { regex: '^bytes\\d*$', tsType: 'string' },
             ];
             if (paramKind === ParamKind.Input) {
-                // web3 allows to pass those an non-bignumbers and that's nice
-                // but it always returns stuff as BigNumbers
+                // web3 and ethers allow to pass those as numbers instead of bignumbers
                 solTypeRegexToTsType.unshift({
                     regex: '^u?int(8|16|32)?$',
                     tsType: 'number|BigNumber',
                 });
             }
+            if (backend === ContractsBackend.Ethers) {
+                if (paramKind === ParamKind.Output) {
+                    // ethers-contracts automatically converts small BigNumbers to numbers
+                    solTypeRegexToTsType.unshift({
+                        regex: '^u?int(8|16|32|48)?$',
+                        tsType: 'number',
+                    });
+                }
+            }
             for (const regexAndTxType of solTypeRegexToTsType) {
                 const { regex, tsType } = regexAndTxType;
                 if (solType.match(regex)) {