Pallet Unit Tests concerning Balances: Modify mock.rs to have ED > 1, to test balances less than ED.

[mattheworris]

As a developer, I would like to create some unit tests for situations when the account balance is less than the Existential Deposit (ED).

Currently, the mocks has ED == 1, so it is not possible to test any situations where ED < 1, which some valid edge cases do exist.

• Modify mock.rs to have ED > 1
• Modify unit tests that are affected by this change.

[Aideepakchaudhary]

@mattheworris Can you please elaborate this issue? like for which pallet you need to update. In todo, i think the condition should be ED < 1.

[mattheworris]

@Aideepakchaudhary
Yes, this issue concerns the capacity and time-release pallets which use the fungible trait to freeze tokens. The issue was created while working on #1779, #1818, and #1873.

Here, the Existential Deposit (ED) for ‎Test::ExistentialDeposit is set to 1. mock.rs defines Test as a simplified version of the pallet used for unit testing.

On testnet/mainnet, ED is set to a larger number = 1_000_000.

Therefore, there are valid scenarios on testnet/mainnet that can result in an account balance that is below ED but greater than 0.

Currently, it is not possible to use mock.rs and Test::ExistentialDeposit to test this scenario, as the only value less than ED in mock.rs is 0.

If Test::ExistentialDeposit is changed to a larger value, e.g. 10, it would allow unit tests to create a scenario where 0 < account_balance < ED.

However, this may also break the logic for the existing tests with ED == 1 and those tests would need to be updated to use the larger ED value.