lesson-9 test error

[TimeKeyRoll]

Does anyone know about this?

[othaime-en]

The detail is in the error message in red. Check if indeed you have the custom error lottery__NotOpen in your contract.
Can I see your solidity code in the error section?

If you indeed have the error lottery__NotOpen, I see you have added a space in line 70 on " lottery__NotOpen" Remove the space. It should be "lottery__NotOpen"

[othaime-en]

Oh that's just some problems with tsconfig.json in your node_modules. Nothing to do your code. Ignore it at the moment.

[TimeKeyRoll]

Okay! And online '67'.. He's adding '+1'.. Where does that coming from and what does that do!?

I have checked in the documention it's not there..

[othaime-en]

Okay if you understood his explanation, "evm_increaseTime" forwards the block timestamp by the amount you add in the args section. And in this case, the args for this method are [interval.toNumber() + 1]. Let's break this down. interval from our helper-hardhat-config file, we know is "30". This is like the period that we have to wait before we pick a new winner (30 seconds). So interval.toNumber() converts the string "30" to the number 30. After this conversion, we add 1 So its 30 + 1 = 31.
We are adding this 1 to make sure that the blocktimestamp is more than the interval (31 is more than 30) so that it is automatically time to pick a winner. We could add any value here, provided it results to a number greater than the interval.

Side Note: Since the interval here is 30 seconds you may not see the essence of pushing time ahead, but this functionality is really useful if your are dealing with a bigger interval value like hours or days.

[TimeKeyRoll]

I understand this. Let's says if it's 24 hours rather than '30' seconds. So the function will work same way. It will use '' evm_increaseTime"" to fast forward the given amount of time(which is mentioned in helper-hardhat) and start to count from '1'(or any no. Of time we mention here than '1') and execute the function. Yeah?

[othaime-en]

Yeah. So if we put 24 hrs (in seconds), the method will just fast forward the block timestamp to 24hrs from now. We don't have to wait for it to count, it just sort of adds the 86400 seconds (1 day) to the current blocktimestamp so that it seems like we are one day ahead.