Create a contract that adheres to the following specifications.

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Contract

Create a contract called WeightedVoting. Add the following:

  • A maxSupply of 1,000,000
  • Errors for:
    • TokensClaimed
    • AllTokensClaimed
    • NoTokensHeld
    • QuorumTooHigh, returning the quorum amount proposed
    • AlreadyVoted
    • VotingClosed
  • A struct called Issue containing:
    • An OpenZeppelin Enumerable Set storing addresses called voters
    • A string issueDesc
    • Storage for the number of votesFor, votesAgainst, votesAbstain, totalVotes, and quorum
    • Bools storing if the issue is passed and closed

The unit tests require this struct to be constructed with the variables in the order above.

  • An array of Issues called issues
  • An enum for Vote containing:
    • AGAINST
    • FOR
    • ABSTAIN
  • Anything else needed to complete the tasks

Add the following functions.

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Constructor

Initialize the ERC-20 token and burn the zeroeth element of issues.

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Claim

Add a public function called claim. When called, so long as a number of tokens equalling the maximumSupply have not yet been distributed, any wallet that has not made a claim previously should be able to claim 100 tokens. If a wallet tries to claim a second time, it should revert with TokensClaimed.

Once all tokens have been claimed, this function should revert with an error AllTokensClaimed.

In our simple token, we used totalSupply to mint our tokens up front. The ERC20 implementation we’re using also tracks totalSupply, but does it differently.

Review the docs and code comments to learn how.

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Create Issue

Implement an external function called createIssue. It should add a new Issue to issues, allowing the user to set the description of the issue, and quorum - which is how many votes are needed to close the issue.

Only token holders are allowed to create issues, and issues cannot be created that require a quorum greater than the current total number of tokens.

This function must return the index of the newly-created issue.

One of the unit tests will break if you place your check for quorum before the check that the user holds a token. The test compares encoded error names, which are not human-readable. If you are getting -> AssertionError: �s is not equal to �9� or similar, this is likely the issue.

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Get Issue

Add an external function called getIssue that can return all of the data for the issue of the provided _id.

EnumerableSet has a mapping underneath, so it can’t be returned outside of the contract. You’ll have to figure something else out.

Hint

The return type for this function should be a struct very similar to the one that stores the issues.

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Vote

Add a public function called vote that accepts an _issueId and the token holder’s vote. The function should revert if the issue is closed, or the wallet has already voted on this issue.

Holders must vote all of their tokens for, against, or abstaining from the issue. This amount should be added to the appropriate member of the issue and the total number of votes collected.

If this vote takes the total number of votes to or above the quorum for that vote, then:

  • The issue should be set so that closed is true
  • If there are more votes for than against, set passed to true

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Submit your Contract and Earn an NFT Badge! (BETA)

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Hey, where’d my NFT go!?

Testnets are not permanent! Base Goerli will soon be sunset, in favor of Base Sepolia.

As these are separate networks with separate data, your NFTs will not transfer over.

Don’t worry! We’ve captured the addresses of all NFT owners on Base Goerli and will include them when we release the mechanism to transfer these NFTs to mainnet later this year! You can also redeploy on Sepolia and resubmit if you’d like!

The contract specification contains actions that can only be performed once by a given address. As a result, the unit tests for a passing contract will only be successful the first time you test.

You may need to submit a fresh deployment to pass