Testing

Some quick examples for techniques for testing.

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Contract Events

Testing ERC-20 Transfer Event

describe('Events', async function() {
    it('triggers a Transfer event', function() {

        let contract = new Contract(contractAddress, abi, accounts[0]);

        let transferEvent = new Promise((resolve, reject) => {
            contract.on('Transfer', (from, to, amount, event) => {
                event.removeListener();

                resolve({
                    from: from,
                    to: to,
                    amount: amount
                });
            });

            setTimeout(() => {
                reject(new Error('timeout'));
            }, 60000)
        });

        let tx = await contract.transfer(accounts[1], 12345);

        let event = await transferEvent;

        assert.equal(event.from, account[0].address);
        assert.equal(event.to, account[1].address);
        assert.equal(event.amount.toNumber(), 12345);
    });
});

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Using Multiple Accounts

Testing Multiple Accounts

describe('Events', async function() {
    it('triggers a Transfer event', function() {

        // Connect to Geth/Parity node on http://localhost:8545
        let provider = new providers.JsonRpcProvider();

        // Get the first two accounts from the Geth/Parity node
        let signer0 = provider.getSigner(0);
        let signer1 = provider.getSigner(1);

        // Read-only connection to the contract
        let contract = new Contract(contractAddress, abi, provider);

        // Read-Write connection to the contract
        let contractAsSigner0 = contract.connect(signer0);
        let contractAsSigner1 = contract.connect(signer1);

        // ...

    });
});

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