Existing method of _signTypedData in Wallet but unable to use?

[dellwatson]

Hello, i'm trying to understand how to use _signTypedData using ethers without eth-sig-util
In Wallet there's method _signTypedData

    async _signTypedData(domain: TypedDataDomain, types: Record<string, Array<TypedDataField>>, value: Record<string, any>): Promise<string> {
        // Populate any ENS names
        const populated = await _TypedDataEncoder.resolveNames(domain, types, value, (name: string) => {
            if (this.provider == null) {
                logger.throwError("cannot resolve ENS names without a provider", Logger.errors.UNSUPPORTED_OPERATION, {
                    operation: "resolveName",
                    value: name
                });
            }
            return this.provider.resolveName(name);
        });

        return joinSignature(this._signingKey().signDigest(_TypedDataEncoder.hash(populated.domain, types, populated.value)));
    }

but im unable to use it

._signTypedData is not a function

so perhaps my initialized of Wallet is wrong, so i tried

const wallet = new Wallet();

but instead i still get error:

Cannot read properties of undefined (reading 'toHexString')

I also tried with Signer but nothing works.
how to use wallet properly and signTypedData?

[dellwatson]

I'm following this guide from devpost

    const metamaskProvider = new ethers.provider.Web3Provider(
            window.ethereum
          );
          const signer = metamaskProvider.getSigner();

but im even unable to get Web3Provider now. TypeError: Cannot read properties of undefined (reading 'Web3Provider')

[dellwatson]

ok i'm missing the s in provider but still had another problem with uint256, as it seems i need to typecast the number first?

[dellwatson]

i casted to BigNumber but still got an error.
i only had problem with uint256

Error: unknown type "maxCount" (argument="types", value={"Presale":[{"name":"buyer","type":"address"},{"name":"uint256","type":"maxCount"}]}, code=INVALID_ARGUMENT, version=hash/5.6.1)

[dellwatson]

nvm, i mistook the place between type and name