imp(costaking): track baby staked to active validators

[GAtom22]

Description

Currently AfterDelegationModified hook will update co-staking tracker no matter val status

This PR introduces the changes to hooks when delegation modified:

• ONLY update baby amt in co-staking tracker if validator was in active set - using staking.IterateLastValidatorPowers

Later on, AfterEpochEnds hook:

• get newly active and inactive validators from:
  • cached staking.IterateLastValidatorPowers - is the prev-epoch validator set
  • staking.IterateLastValidatorPowers - returns the new epoch validators (updated before calling the hook)
• if validator becomes inactive:
  • In case was add before - OK, will reduce the corresponding total amount
  • In case was reduced before - OK, will reduce the remaining (validator delegations already updated)
• if validator becomes active:
  • update all delegators co-staking trackers

[Copilot]

Pull Request Overview

This PR modifies the co-staking tracking system to only track baby tokens staked to active validators, implementing proper validator set management and epoch-based transitions.

Key changes:

• Only process delegation hooks for active validators (using IterateLastValidatorPowers)
• Add epoch-end hook to handle validator transitions between active/inactive states
• Update initialization logic to consider validator active status

Reviewed Changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
x/costaking/types/staking_cache.go	Add active validator set caching functionality
x/costaking/types/mocked_keepers.go	Add mock methods for validator delegations and power iteration
x/costaking/types/expected_keepers.go	Add required staking keeper interface methods
x/costaking/keeper/hooks_staking_test.go	Add comprehensive tests for active/inactive validator scenarios
x/costaking/keeper/hooks_staking.go	Implement active validator checks in delegation hooks
x/costaking/keeper/hooks_epoching_test.go	Add tests for epoch-based validator transitions
x/costaking/keeper/hooks_epoching.go	Implement epoch hooks for validator state transitions
test/e2ev2/tmanager/genesis.go	Remove trailing whitespace
app/upgrades/v4/upgrades_costaking_test.go	Update tests to properly handle active validator scenarios
app/upgrades/v4/upgrades.go	Update initialization to only process active validators
app/keepers/keepers.go	Register co-staking epoch hooks
CHANGELOG.md	Add entry for the change

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[KonradStaniec]

In general looks good 👍 I have some doubts about the caching thing, which seems to be making some implicit assumptions when cache is filled.

Also, do you think it is feasible to create some e2e test in which we have 2 validators and we jail one of them to see that active baby drops to 0 for certain delegators ?

[GAtom22]

do you think it is feasible to create some e2e test in which we have 2 validators and we jail one of them to see that active baby drops to 0 for certain delegators ?

Sure, will work on this

[GAtom22]

Note that the upgrade with these changes should be done at epoch boundary to store the validator set data on upgrading

[Copilot]

Pull Request Overview

Copilot reviewed 40 out of 41 changed files in this pull request and generated 4 comments.

Comments suppressed due to low confidence (1)

x/costaking/keeper/hooks_staking.go:1

• This function doesn't use the provided valInfo parameter for token calculation, making the parameter misleading. Consider either using valInfo data or removing it from the signature.

package keeper

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[RafilxTenfen]

LGTM, good job @GAtom22 🎉

[KonradStaniec]

Looks good, great job finding all edge cases and adding all tests 👍

Just one question, related to iterating over maps.