Writing test cases in Blockchain / Solidity - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a simple test case function.

Blockchain / Solidity

function test[1]() {
  // test logic here
}

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ATest

BCase

CRun

DCheck

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic names like 'Run' or 'Check' instead of 'Test'.

The function name should start with test to indicate it is a test case.

2fill in blank

medium

Complete the code to assert that a smart contract function returns true.

Blockchain / Solidity

assert.equal(contract.[1](), true);

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Arun

BisActive

Cexecute

Dtransfer

Attempts:

3 left

💡 Hint

Common Mistakes

Using functions that do not return booleans like 'transfer' or 'run'.

The function isActive is expected to return a boolean value, so asserting it equals true makes sense.

3fill in blank

hard

Fix the error in the test case to correctly check the balance after transfer.

Blockchain / Solidity

const balance = await contract.getBalance([1]);
assert.equal(balance.toNumber(), 100);

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Aaccount

Breceiver

Caddress

Dsender

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic terms like 'sender' or 'account' that may not be defined.

The getBalance function expects an address parameter to check the balance of that account.

4fill in blank

hard

Fill both blanks to write a test that checks if a transaction reverts with an error.

Blockchain / Solidity

await expect(contract.[1](100)).to.be.revertedWith([2]);

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Atransfer

Bapprove

C'Insufficient balance'

D'Unauthorized'

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong function names or error messages that don't match the test scenario.

The test checks that calling transfer with 100 tokens reverts with the error message 'Insufficient balance'.

5fill in blank

hard

Fill all three blanks to create a test that verifies an event is emitted with correct parameters.

Blockchain / Solidity

await expect(contract.[1](user, 50))
  .to.emit(contract, '[2]')
  .withArgs([3]);

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Amint

BTransfer

Cuser, 50

DBurn

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong event names or incorrect event argument formats.

This test calls the mint function, expects the Transfer event, and checks that the event arguments are user and 50.