test(gov): add test for Tally function

[tbruyelle]

Description

Although rather complex, the govKeeper.Tally function has no unit tests. This change adds a test that covers around 91% of the code, only some unexpected errors are not covered.

If this change is accepted, another will follow to refactor the function into smaller parts (without changing the test). This will address the TODO on top, reduce complexity, improve readability and reusability.

This test should also help for issues like #11422 and #10353. It's more comfortable to improve performance or completely rewrite the implementation with a high code coverage.

The setupGovKeeper had to be modified because it was registering some mocks expectations that cannot be overridden. It now takes an additional variadic argument that can be used to better customize the mocks expectations. Also, to improve readability, the mocks are all gathered in a new specific mocks struct.

Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
• run make lint and make test
• confirmed all CI checks have passed

Reviewers Checklist

All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• confirmed all author checklist items have been addressed
• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

[julienrbrt]

Nice! Yeah, units tests weren't created when we moved the previous tests to the integration folder (https://github.com/cosmos/cosmos-sdk/blob/6b4774266eeb03748937faf28663019ac332cc9c/tests/integration/gov/keeper/tally_test.go).

[tbruyelle]

Nice! Yeah, units tests weren't created when we moved the previous tests to the integration folder (https://github.com/cosmos/cosmos-sdk/blob/6b4774266eeb03748937faf28663019ac332cc9c/tests/integration/gov/keeper/tally_test.go).

Oh I hadn't noticed those tests before, thanks for bringing them to my attention. I assume both unit and integration tests are welcome :).

[julienrbrt]

Nice! Yeah, units tests weren't created when we moved the previous tests to the integration folder (6b47742/tests/integration/gov/keeper/tally_test.go).

Oh I hadn't noticed those tests before, thanks for bringing them to my attention. I assume both unit and integration tests are welcome :).

For sure!