Metamask: Metamask showing error but works from console

Metamask Error: Contract Code Not Validated

As a developer working with smart contracts on the Ethereum blockchain, you have probably encountered issues when deploying and interacting with your contracts. One of the most frustrating experiences is when your contract code does not validate correctly in either the web-based development environment (web3.js) or the Metamask mobile wallet app.

In this article, we will examine the issue you are experiencing and provide a step-by-step guide to resolving the problem using Metamask’s console output.

The Problem: Contract Code Error in Metamask Console

When you try to invoke your contract in MetaMask’s console environment to deposit funds to itself, an error occurs indicating problems validating the contract code. This is not typical behavior for most contracts as they are expected to validate their own code correctly.

To fix this issue, let’s examine the “web3.utils.toWei()” function and what might be causing the problem:

let ethAmount = this.web3.utils.toWei(...); // Error: invalid argument type

In your case, you seem to be trying to convert the Ethereum amount of Wei (a unit of Ether) to a standard decimal representation. However, there is a problem with the second argument passed to “toWei()”.

Possible Causes and Solutions

• Incorrect Function Signature: Make sure the function signature in your contract is correct:

Function DepositAmount(EtherAmount: uint256) public {
// ...
}

• Invalid or missing arguments: Check that you have included all required arguments when calling “depositAmount()”. Make sure the second argument (“etherAmount”) is of the expected type.

• Type inference error: Ethereum’s “toWei()” function requires specific types for its arguments. If your contract is written in Solidity, make sure it uses the correct types:

Function DepositAmount(EthereumAmount: uint256) public {
// ...
}

Solutions to fix the issue

To fix this issue, you can try one or more of the following solutions:

• Add type annotations: If your contract is written in Solidity (e.g. .sol), add type annotations for the etherAmount argument:

Function DepositAmount(EthereumAmount: uint256) public {
// ...
}

• Use a more robust contract validation library: Consider using libraries like OpenZeppelin’s contract-validation or eip172 to validate your contract code and avoid type errors.

Conclusion

To resolve the issue of validation errors in contract code in Metamask, make sure your contract is written with correct function signatures, includes all required arguments, and uses the expected types. If you still have issues after trying these solutions, please provide further context or code snippets about your project and I’ll do my best to help you further.

Example Use Case

Here is an updated example of how to use web3.utils.toWei() with type annotations:

Pragma Solid ^0,8.0;
Contract DepositAmount {
Function DepositAmount(EthereumAmount: uint256) public {
require(ethereumAmount != 0, "Invalid amount");
// ...
}
}

Note that this is just a simple example and may not cover all edge cases. Make sure to thoroughly test your contract in both the web-based development environment (web3.js) and the Metamask wallet mobile app.