feat: exclude the gas field from the codegen abi in target-ethers-v5

Author: frontier159

packages/target-ethers-v5/src/codegen/index.ts

@@ -241,18 +241,20 @@ export function codegenAbstractContractFactory(contract: Contract, abi: any): st
 }
 
 // Earlier versions of the vyper compiler included the 'gas' estimates as a member
-// in the generated abi object.
-// This breaks the auto-generation code, so it's manually excluded.
-function stringifyAbi(_abi: any): string {
-  if (typeof _abi === 'object') {
-    const abiNoGas = _abi.map((element: any) => {
+// in the vyper-generated abi object.
+// This breaks the typechain auto-generation code, since gas is a number and not stringified.
+// Further, even if it were stringified, the gas estimates are generally incorrect.
+// So the 'gas' member is manually removed from the abi in the generated typechain.
+function stringifyAbi(abi: any): string {
+  if (typeof abi === 'object') {
+    const abiNoGas = abi.map((element: any) => {
       const { gas: _, ...withoutGas } = element
       return withoutGas
     })
     return JSON.stringify(abiNoGas, null, 2)
   }
 
-  return JSON.stringify(_abi, null, 2)
+  return JSON.stringify(abi, null, 2)
 }
 
 function codegenCommonContractFactory(contract: Contract, abi: any): { header: string; body: string } {

packages/target-ethers-v5/test/generation.test.ts

@@ -37,6 +37,35 @@ describe('Ethers generation edge cases', () => {
     expect(source).toEqual(expect.stringMatching(/export class TestContract__factory extends ContractFactory \{/))
     expect(source).toEqual(expect.stringMatching(/static linkBytecode\(/))
   })
+
+  it('should exclude gas field from ABI', () => {
+    const abi = [
+      {
+        stateMutability: 'view',
+        type: 'function',
+        name: 'foo',
+        inputs: [
+          {
+            name: 'bar',
+            type: 'address',
+          },
+        ],
+        outputs: [
+          {
+            name: '',
+            type: 'uint256',
+          },
+        ],
+        gas: 3135,
+      },
+    ]
+
+    const source = codegenContractFactory(DEFAULT_FLAGS, emptyContract, abi, {
+      bytecode: '{{BYTECODE}}',
+    })
+
+    expect(source).not.toEqual(expect.stringMatching(/"gas":/))
+  })
 })
 
 describe(generateEventFilters.name, () => {