Allow for custom transaction properties

ethers/contract.nim

@@ -47,10 +47,14 @@ template raiseContractError(message: string) =
 
 proc createTransaction(contract: Contract,
                        function: string,
-                       parameters: tuple): Transaction =
+                       parameters: tuple,
+                       overrides = Transaction.default): Transaction =
   let selector = selector(function, typeof parameters).toArray
   let data = @selector & AbiEncoder.encode(parameters)
-  Transaction(to: contract.address, data: data)
+  var transaction = overrides
+  transaction.to = contract.address
+  transaction.data = data
+  return transaction
 
 proc decodeResponse(T: type, multiple: static bool, bytes: seq[byte]): T =
   when multiple:
@@ -77,11 +81,13 @@ proc call(contract: Contract,
   let response = await contract.provider.call(transaction, blockTag)
   return decodeResponse(ReturnType, returnMultiple, response)
 
-proc send(contract: Contract, function: string, parameters: tuple):
-    Future[?TransactionResponse] {.async.} =
-
+proc send(contract: Contract,
+          function: string,
+          parameters: tuple,
+          overrides = Transaction.default):
+         Future[?TransactionResponse] {.async.} =
   if signer =? contract.signer:
-    let transaction = createTransaction(contract, function, parameters)
+    let transaction = createTransaction(contract, function, parameters, overrides)
     let populated = await signer.populateTransaction(transaction)
     let txResp = await signer.sendTransaction(populated)
     return txResp.some
@@ -111,6 +117,15 @@ func isMultipleReturn(returnType: NimNode): bool =
   (returnType.kind == nnkTupleConstr) or
   (returnType.kind == nnkTupleTy)
 
+func addOverrides(procedure: var NimNode) =
+  procedure[3].add(
+    newIdentDefs(
+      ident("overrides"),
+      newEmptyNode(),
+      quote do: Transaction.default
+    )
+  )
+
 func addContractCall(procedure: var NimNode) =
   let contract = procedure[3][1][0]
   let function = $basename(procedure[0])
@@ -118,6 +133,8 @@ func addContractCall(procedure: var NimNode) =
   let returnType = procedure[3][0]
   let returnMultiple = returnType.isMultipleReturn.newLit
 
+  procedure.addOverrides()
+
   func call: NimNode =
     if returnType.kind == nnkEmpty:
       quote:
@@ -130,12 +147,12 @@ func addContractCall(procedure: var NimNode) =
   func send: NimNode =
     if returnType.kind == nnkEmpty:
       quote:
-        discard await send(`contract`, `function`, `parameters`)
+        discard await send(`contract`, `function`, `parameters`, overrides)
     else:
       quote:
         when typeof(result) isnot Confirmable:
           {.error: "unexpected return type, missing {.view.} or {.pure.} ?".}
-        return await send(`contract`, `function`, `parameters`)
+        return await send(`contract`, `function`, `parameters`, overrides)
 
   procedure[6] =
     if procedure.isConstant:

testmodule/mocks.nim

@@ -0,0 +1,20 @@
+import pkg/ethers
+
+type MockSigner* = ref object of Signer
+  provider: Provider
+  address*: Address
+  transactions*: seq[Transaction]
+
+func new*(_: type MockSigner, provider: Provider): MockSigner =
+  MockSigner(provider: provider)
+
+method provider*(signer: MockSigner): Provider =
+  signer.provider
+
+method getAddress*(signer: MockSigner): Future[Address] {.async.} =
+  return signer.address
+
+method sendTransaction*(signer: MockSigner,
+                        transaction: Transaction):
+                       Future[TransactionResponse] {.async.} =
+  signer.transactions.add(transaction)

testmodule/testContracts.nim

@@ -5,6 +5,7 @@ import pkg/stint
 import pkg/ethers
 import ./hardhat
 import ./miner
+import ./mocks
 
 type
 
@@ -112,6 +113,19 @@ suite "Contracts":
     check (await token.connect(provider).balanceOf(accounts[1])) == 25.u256
     check (await token.connect(provider).balanceOf(accounts[2])) == 25.u256
 
+  test "takes custom values for nonce, gasprice and gaslimit":
+    let overrides = Transaction(
+      nonce: some 100.u256,
+      gasPrice: some 200.u256,
+      gasLimit: some 300.u256
+    )
+    let signer = MockSigner.new(provider)
+    discard await token.connect(signer).mint(accounts[0], 42.u256, overrides)
+    check signer.transactions.len == 1
+    check signer.transactions[0].nonce == overrides.nonce
+    check signer.transactions[0].gasPrice == overrides.gasPrice
+    check signer.transactions[0].gasLimit == overrides.gasLimit
+
   test "receives events when subscribed":
     var transfers: seq[Transfer]