Use Result to return error when wallet creation fails

Co-authored-by: Eric Mastro <[email protected]>

Author: markspanbroek

ethers/wallet.nim

@@ -30,16 +30,15 @@ proc new*(_: type Wallet, privateKey: PrivateKey, provider: Provider): Wallet =
   let wallet = Wallet.new(privateKey)
   wallet.provider = some provider
   wallet
-proc new*(_: type Wallet, privateKey: string): ?Wallet =
-  if key =? PrivateKey.fromHex(privateKey):
-    some Wallet.new(key)
-  else:
-    none Wallet
-proc new*(_: type Wallet, privateKey: string, provider: Provider): ?Wallet =
-  if key =? PrivateKey.fromHex(privateKey):
-    some Wallet.new(key, provider)
-  else:
-    none Wallet
+proc new*(_: type Wallet, privateKey: string): ?!Wallet =
+  let keyResult = PrivateKey.fromHex(privateKey)
+  if keyResult.isErr:
+    return failure newException(WalletError, "invalid key: " & $keyResult.error)
+  success Wallet.new(keyResult.get())
+proc new*(_: type Wallet, privateKey: string, provider: Provider): ?!Wallet =
+  let wallet = ? Wallet.new(privateKey)
+  wallet.provider = some provider
+  success wallet
 proc connect*(wallet: Wallet, provider: Provider) =
   wallet.provider = some provider
 proc createRandom*(_: type Wallet): Wallet =

testmodule/testWallet.nim

@@ -21,20 +21,20 @@ suite "Wallet":
     await provider.close()
 
   test "Can create Wallet with private key":
-    check isSome Wallet.new(pk1)
+    check isSuccess Wallet.new(pk1)
     discard Wallet.new(PrivateKey.fromHex(pk1).get)
 
   test "Private key can start with 0x":
-    check isSome Wallet.new("0x" & pk1)
+    check isSuccess Wallet.new("0x" & pk1)
 
   test "Can create Wallet with provider":
     let provider = JsonRpcProvider.new()
-    check isSome Wallet.new(pk1, provider)
+    check isSuccess Wallet.new(pk1, provider)
     discard Wallet.new(PrivateKey.fromHex(pk1).get, provider)
 
   test "Cannot create wallet with invalid key string":
-    check isNone Wallet.new("0xInvalidKey")
-    check isNone Wallet.new("0xInvalidKey", JsonRpcProvider.new())
+    check isFailure Wallet.new("0xInvalidKey")
+    check isFailure Wallet.new("0xInvalidKey", JsonRpcProvider.new())
 
   test "Can connect Wallet to provider":
     let wallet = !Wallet.new(pk1)