diff --git a/pallets/subtensor/src/migrations/migrate_delete_subnet_3.rs b/pallets/subtensor/src/migrations/migrate_delete_subnet_3.rs index 0cda0f0e06..1a16933ff0 100644 --- a/pallets/subtensor/src/migrations/migrate_delete_subnet_3.rs +++ b/pallets/subtensor/src/migrations/migrate_delete_subnet_3.rs @@ -120,6 +120,199 @@ pub fn migrate_delete_subnet_3() -> Weight { } } -// TODO: Add unit tests for this migration -// TODO: Consider adding error handling for storage operations -// TODO: Verify that all relevant storage items for subnet 3 are removed + +#[cfg(test)] +mod tests { + use super::*; + use crate::tests::mock::*; + use frame_support::traits::{GetStorageVersion, StorageVersion}; + use sp_core::U256; + + /// Test that migration runs successfully when conditions are met + #[test] + fn test_migrate_delete_subnet_3_success() { + new_test_ext(1).execute_with(|| { + // Setup: Create subnet 3 + let netuid = NetUid::from(3); + add_network(netuid, 100, 0); + + // Register some neurons to populate storage + let hotkey = U256::from(1); + let coldkey = U256::from(2); + register_ok_neuron(netuid, hotkey, coldkey, 0); + + // Verify subnet exists before migration + assert!(Pallet::::if_subnet_exist(netuid)); + assert_eq!(TotalNetworks::::get(), 1); + + // Set storage version to 4 (less than new version 5) + StorageVersion::new(4).put::>(); + + // Run migration + let weight = migrate_delete_subnet_3::(); + + // Verify migration executed + assert!(weight != Weight::zero()); + + // Verify subnet 3 is removed + assert!(!Pallet::::if_subnet_exist(netuid)); + assert_eq!(TotalNetworks::::get(), 0); + + // Verify storage version updated + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(5)); + + // Verify network registration data removed + assert!(!NetworksAdded::::contains_key(netuid)); + assert!(!NetworkRegisteredAt::::contains_key(netuid)); + }); + } + + /// Test that migration skips when already completed (version check) + #[test] + fn test_migrate_delete_subnet_3_already_migrated() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 5 or higher + StorageVersion::new(5).put::>(); + + // Create subnet 3 that should NOT be deleted + let netuid = NetUid::from(3); + add_network(netuid, 100, 0); + + // Run migration + let weight = migrate_delete_subnet_3::(); + + // Verify migration was skipped (zero weight) + assert_eq!(weight, Weight::zero()); + + // Verify subnet 3 still exists + assert!(Pallet::::if_subnet_exist(netuid)); + }); + } + + /// Test that migration skips when subnet 3 doesn't exist + #[test] + fn test_migrate_delete_subnet_3_subnet_not_exist() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 4 but don't create subnet 3 + StorageVersion::new(4).put::>(); + + // Verify subnet 3 doesn't exist + assert!(!Pallet::::if_subnet_exist(NetUid::from(3))); + + // Run migration + let weight = migrate_delete_subnet_3::(); + + // Verify migration was skipped + assert_eq!(weight, Weight::zero()); + }); + } + + /// Test that all relevant storage items for subnet 3 are removed + #[test] + fn test_migrate_delete_subnet_3_storage_cleanup() { + new_test_ext(1).execute_with(|| { + // Setup: Create subnet 3 with full storage + let netuid = NetUid::from(3); + add_network(netuid, 100, 0); + + let hotkey = U256::from(1); + let coldkey = U256::from(2); + register_ok_neuron(netuid, hotkey, coldkey, 0); + + // Manually set additional storage items that should be cleaned up + Tempo::::insert(netuid, 100); + Kappa::::insert(netuid, 100); + Difficulty::::insert(netuid, 10000); + MaxAllowedUids::::insert(netuid, 100); + ImmunityPeriod::::insert(netuid, 100); + ActivityCutoff::::insert(netuid, 100); + + // Set storage version + StorageVersion::new(4).put::>(); + + // Run migration + let weight = migrate_delete_subnet_3::(); + + // Verify migration executed + assert!(weight != Weight::zero()); + + // Verify all storage items removed + assert!(!SubnetworkN::::contains_key(netuid)); + assert!(!NetworksAdded::::contains_key(netuid)); + assert!(!NetworkRegisteredAt::::contains_key(netuid)); + assert!(!Rank::::contains_key(netuid)); + assert!(!Trust::::contains_key(netuid)); + assert!(!Active::::contains_key(netuid)); + assert!(!Emission::::contains_key(netuid)); + assert!(!Consensus::::contains_key(netuid)); + assert!(!Dividends::::contains_key(netuid)); + assert!(!PruningScores::::contains_key(netuid)); + assert!(!ValidatorPermit::::contains_key(netuid)); + assert!(!ValidatorTrust::::contains_key(netuid)); + assert!(!Tempo::::contains_key(netuid)); + assert!(!Kappa::::contains_key(netuid)); + assert!(!Difficulty::::contains_key(netuid)); + assert!(!MaxAllowedUids::::contains_key(netuid)); + assert!(!ImmunityPeriod::::contains_key(netuid)); + assert!(!ActivityCutoff::::contains_key(netuid)); + assert!(!MinAllowedWeights::::contains_key(netuid)); + assert!(!RegistrationsThisInterval::::contains_key(netuid)); + assert!(!POWRegistrationsThisInterval::::contains_key(netuid)); + assert!(!BurnRegistrationsThisInterval::::contains_key(netuid)); + }); + } + + /// Test that weight calculation is accurate for migration + #[test] + fn test_migrate_delete_subnet_3_weight_calculation() { + new_test_ext(1).execute_with(|| { + // Setup + let netuid = NetUid::from(3); + add_network(netuid, 100, 0); + StorageVersion::new(4).put::>(); + + // Run migration + let weight = migrate_delete_subnet_3::(); + + // Verify weight is non-zero and includes all expected operations + // Weight should include: + // - 1 read (version check) + // - 5 writes (initial removals) + // - 4 writes (prefix clears) + // - 11 writes (network parameters) + // - 10 writes (erase parameters) + // - 1 write (storage version update) + // Total: 1 read + 31 writes minimum + assert!(weight.ref_time() > 0); + + let expected_min_weight = Test::DbWeight::get().reads(1) + .saturating_add(Test::DbWeight::get().writes(31)); + + assert!(weight.ref_time() >= expected_min_weight.ref_time()); + }); + } + + /// Test migration preserves other subnets + #[test] + fn test_migrate_delete_subnet_3_preserves_other_subnets() { + new_test_ext(1).execute_with(|| { + // Setup: Create subnet 1, 2, and 3 + add_network(NetUid::from(1), 100, 0); + add_network(NetUid::from(2), 100, 0); + add_network(NetUid::from(3), 100, 0); + + assert_eq!(TotalNetworks::::get(), 3); + + StorageVersion::new(4).put::>(); + + // Run migration + migrate_delete_subnet_3::(); + + // Verify only subnet 3 removed + assert!(Pallet::::if_subnet_exist(NetUid::from(1))); + assert!(Pallet::::if_subnet_exist(NetUid::from(2))); + assert!(!Pallet::::if_subnet_exist(NetUid::from(3))); + assert_eq!(TotalNetworks::::get(), 2); + }); + } +} diff --git a/pallets/subtensor/src/migrations/migrate_to_v1_separate_emission.rs b/pallets/subtensor/src/migrations/migrate_to_v1_separate_emission.rs index f6816b291d..ce5da89c7f 100644 --- a/pallets/subtensor/src/migrations/migrate_to_v1_separate_emission.rs +++ b/pallets/subtensor/src/migrations/migrate_to_v1_separate_emission.rs @@ -99,6 +99,216 @@ pub fn migrate_to_v1_separate_emission() -> Weight { } } -// TODO: Add unit tests for this migration -// TODO: Consider adding error handling for edge cases -// TODO: Verify that all possible states of the old format are handled correctly + +#[cfg(test)] +mod tests { + use super::*; + use crate::tests::mock::*; + use frame_support::traits::{GetStorageVersion, StorageVersion}; + use sp_core::U256; + + /// Test successful migration from old to new emission format + #[test] + fn test_migrate_to_v1_separate_emission_success() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 0 (old version) + StorageVersion::new(0).put::>(); + + // Create test data in old format: Vec<(AccountId, validator_emission)> + let netuid = NetUid::from(1); + let server1 = U256::from(100); + let server2 = U256::from(200); + let old_emissions = vec![ + (server1, 1000_u64), + (server2, 2000_u64), + ]; + + // Insert old format data using deprecated storage + deprecated_loaded_emission_format::LoadedEmission::::insert( + netuid.into(), + old_emissions.clone(), + ); + + // Run migration + let weight = migrate_to_v1_separate_emission::(); + + // Verify migration executed (non-zero weight) + assert!(weight != Weight::zero()); + + // Verify storage version updated to 1 + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(1)); + + // Verify data translated to new format: Vec<(AccountId, server_emission, validator_emission)> + let new_emissions = LoadedEmission::::get(netuid).unwrap(); + assert_eq!(new_emissions.len(), 2); + + // Old validator emissions should be preserved, server emissions should be 0 + assert_eq!(new_emissions[0], (server1, 0_u64, 1000_u64)); + assert_eq!(new_emissions[1], (server2, 0_u64, 2000_u64)); + }); + } + + /// Test that migration skips when already completed + #[test] + fn test_migrate_to_v1_separate_emission_already_migrated() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 1 or higher + StorageVersion::new(1).put::>(); + + // Run migration + let weight = migrate_to_v1_separate_emission::(); + + // Verify migration was skipped (zero weight) + assert_eq!(weight, Weight::zero()); + + // Verify version unchanged + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(1)); + }); + } + + /// Test handling of multiple netuids with old format data + #[test] + fn test_migrate_to_v1_separate_emission_multiple_netuids() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(0).put::>(); + + // Setup multiple netuids with old format data + for netuid_val in 1..=3 { + let netuid = NetUid::from(netuid_val); + let server = U256::from(netuid_val as u64 * 100); + let old_emissions = vec![(server, netuid_val as u64 * 1000)]; + + deprecated_loaded_emission_format::LoadedEmission::::insert( + netuid.into(), + old_emissions, + ); + } + + // Run migration + let weight = migrate_to_v1_separate_emission::(); + + // Verify migration executed + assert!(weight != Weight::zero()); + + // Verify all netuids migrated correctly + for netuid_val in 1..=3 { + let netuid = NetUid::from(netuid_val); + let new_emissions = LoadedEmission::::get(netuid).unwrap(); + assert_eq!(new_emissions.len(), 1); + + let expected_server = U256::from(netuid_val as u64 * 100); + let expected_validator_emission = netuid_val as u64 * 1000; + assert_eq!(new_emissions[0], (expected_server, 0_u64, expected_validator_emission)); + } + }); + } + + /// Test handling of empty emissions data + #[test] + fn test_migrate_to_v1_separate_emission_empty_data() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(0).put::>(); + + // Setup netuid with empty emissions + let netuid = NetUid::from(1); + let empty_emissions: Vec<(U256, u64)> = vec![]; + + deprecated_loaded_emission_format::LoadedEmission::::insert( + netuid.into(), + empty_emissions, + ); + + // Run migration + let weight = migrate_to_v1_separate_emission::(); + + // Verify migration executed + assert!(weight != Weight::zero()); + + // Verify empty data handled correctly + let new_emissions = LoadedEmission::::get(netuid).unwrap(); + assert_eq!(new_emissions.len(), 0); + }); + } + + /// Test weight calculation includes all operations + #[test] + fn test_migrate_to_v1_separate_emission_weight_calculation() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(0).put::>(); + + // Setup test data + let netuid = NetUid::from(1); + let server = U256::from(100); + let old_emissions = vec![(server, 1000_u64)]; + + deprecated_loaded_emission_format::LoadedEmission::::insert( + netuid.into(), + old_emissions, + ); + + // Run migration + let weight = migrate_to_v1_separate_emission::(); + + // Verify weight includes: + // - Initial version read + // - Read old emission data + // - Write new emission data + // - Write storage version + assert!(weight.ref_time() > 0); + + let expected_min_weight = Test::DbWeight::get().reads(2) + .saturating_add(Test::DbWeight::get().writes(2)); + + assert!(weight.ref_time() >= expected_min_weight.ref_time()); + }); + } + + /// Test that old format states are handled correctly + #[test] + fn test_migrate_to_v1_separate_emission_preserves_validator_emissions() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(0).put::>(); + + // Setup with various validator emission values + let netuid = NetUid::from(1); + let test_cases = vec![ + (U256::from(1), 0_u64), // Zero emission + (U256::from(2), 1_u64), // Minimal emission + (U256::from(3), u64::MAX / 2), // Large emission + ]; + + deprecated_loaded_emission_format::LoadedEmission::::insert( + netuid.into(), + test_cases.clone(), + ); + + // Run migration + migrate_to_v1_separate_emission::(); + + // Verify all values preserved correctly + let new_emissions = LoadedEmission::::get(netuid).unwrap(); + assert_eq!(new_emissions.len(), test_cases.len()); + + for (idx, (server, validator_emission)) in test_cases.iter().enumerate() { + assert_eq!(new_emissions[idx], (*server, 0_u64, *validator_emission)); + } + }); + } + + /// Test migration with no old data present + #[test] + fn test_migrate_to_v1_separate_emission_no_old_data() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(0).put::>(); + + // Don't insert any old data + + // Run migration + let weight = migrate_to_v1_separate_emission::(); + + // Verify migration still completes and updates version + assert!(weight != Weight::zero()); + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(1)); + }); + } +} diff --git a/pallets/subtensor/src/migrations/migrate_to_v2_fixed_total_stake.rs b/pallets/subtensor/src/migrations/migrate_to_v2_fixed_total_stake.rs index c8ea6a33af..92f6721549 100644 --- a/pallets/subtensor/src/migrations/migrate_to_v2_fixed_total_stake.rs +++ b/pallets/subtensor/src/migrations/migrate_to_v2_fixed_total_stake.rs @@ -98,6 +98,109 @@ pub fn migrate_to_v2_fixed_total_stake() -> Weight { } } -// TODO: Add unit tests for this migration function -// TODO: Consider adding error handling for potential arithmetic overflow -// TODO: Optimize the iteration over Stake map if possible to reduce database reads + +#[cfg(test)] +mod tests { + use super::*; + use crate::tests::mock::*; + use frame_support::traits::{GetStorageVersion, StorageVersion}; + + /// Test that migration correctly skips when version check fails + #[test] + fn test_migrate_to_v2_fixed_total_stake_version_check() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 2 or higher (already migrated) + StorageVersion::new(2).put::>(); + + // Run migration + let weight = migrate_to_v2_fixed_total_stake::(); + + // Verify migration was skipped (zero weight) + assert_eq!(weight, Weight::zero()); + + // Verify version unchanged + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(2)); + }); + } + + /// Test that migration skips when version is exactly 2 + #[test] + fn test_migrate_to_v2_fixed_total_stake_exact_version() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to exactly 2 + StorageVersion::new(2).put::>(); + + // Run migration + let weight = migrate_to_v2_fixed_total_stake::(); + + // Verify migration skipped + assert_eq!(weight, Weight::zero()); + }); + } + + /// Test migration behavior with version 1 (should trigger check but logic is disabled) + #[test] + fn test_migrate_to_v2_fixed_total_stake_version_1_disabled_migration() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 1 (should trigger migration check) + StorageVersion::new(1).put::>(); + + // Run migration - note the actual migration logic is commented out (TODO line 58) + let weight = migrate_to_v2_fixed_total_stake::(); + + // Currently returns only the read weight since migration logic is disabled + let expected_weight = Test::DbWeight::get().reads(1); + assert_eq!(weight, expected_weight); + + // Version is NOT updated because migration logic is disabled + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(1)); + }); + } + + /// Test weight calculation when migration is skipped + #[test] + fn test_migrate_to_v2_fixed_total_stake_skip_weight() { + new_test_ext(1).execute_with(|| { + // Setup version that causes skip + StorageVersion::new(3).put::>(); + + // Run migration + let weight = migrate_to_v2_fixed_total_stake::(); + + // Should return zero weight for skipped migration + assert_eq!(weight, Weight::zero()); + assert_eq!(weight.ref_time(), 0); + }); + } + + // NOTE: The following tests would be relevant if the migration logic is re-enabled + // Currently, the migration implementation is commented out (see line 58: TODO: Fix or remove migration) + // If re-enabled, these test scenarios should be implemented: + + // TODO: If migration is re-enabled, add test for TotalStake reset and recalculation + // #[test] + // fn test_migrate_to_v2_fixed_total_stake_total_stake_recalculation() { ... } + + // TODO: If migration is re-enabled, add test for TotalColdkeyStake reset and recalculation + // #[test] + // fn test_migrate_to_v2_fixed_total_stake_coldkey_stake_recalculation() { ... } + + // TODO: If migration is re-enabled, add test for arithmetic overflow protection + // #[test] + // fn test_migrate_to_v2_fixed_total_stake_overflow_protection() { ... } + + // TODO: If migration is re-enabled, add test for storage iteration weight calculation + // #[test] + // fn test_migrate_to_v2_fixed_total_stake_iteration_weight() { ... } +} + +// MIGRATION STATUS DOCUMENTATION: +// This migration function is currently DISABLED (see line 58). +// The entire migration logic for resetting and recalculating TotalStake and TotalColdkeyStake +// is commented out. This appears to be intentional based on the TODO comment. +// +// Decision needed: +// 1. If migration should be removed entirely: Delete this file and remove from mod.rs +// 2. If migration should be fixed and re-enabled: Uncomment the logic, add proper error +// handling with saturating arithmetic, and implement the additional test cases noted above +// 3. If migration should remain disabled: Document why and when it might be re-enabled diff --git a/pallets/subtensor/src/migrations/migrate_total_issuance.rs b/pallets/subtensor/src/migrations/migrate_total_issuance.rs index e87337b74e..8080dd563d 100644 --- a/pallets/subtensor/src/migrations/migrate_total_issuance.rs +++ b/pallets/subtensor/src/migrations/migrate_total_issuance.rs @@ -8,7 +8,220 @@ use frame_support::{ }; use sp_std::vec::Vec; -// TODO: Implement comprehensive tests for this migration + + +#[cfg(test)] +mod tests { + use super::*; + use crate::tests::mock::*; + use frame_support::traits::{GetStorageVersion, StorageVersion}; + use sp_core::U256; + use subtensor_runtime_common::TaoCurrency; + + /// Test successful migration path + #[test] + fn test_migrate_total_issuance_success() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 5 + StorageVersion::new(5).put::>(); + + // Create some stake data + let hotkey1 = U256::from(1); + let hotkey2 = U256::from(2); + let coldkey = U256::from(100); + + // Add networks and register neurons to create stake + let netuid = NetUid::from(1); + add_network(netuid, 100, 0); + register_ok_neuron(netuid, hotkey1, coldkey, 0); + register_ok_neuron(netuid, hotkey2, coldkey, 100); + + // Set some stake values + let stake_amount = TaoCurrency::from(1000); + TotalHotkeyStake::::insert(hotkey1, stake_amount); + TotalHotkeyStake::::insert(hotkey2, stake_amount); + Owner::::insert(hotkey1, coldkey); + Owner::::insert(hotkey2, coldkey); + + // Run migration + let weight = migrate_total_issuance::(false); + + // Verify migration executed (non-zero weight) + assert!(weight != Weight::zero()); + + // Verify storage version updated to 6 + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(6)); + + // Verify TotalIssuance was updated + let total_issuance = TotalIssuance::::get(); + assert!(total_issuance > TaoCurrency::ZERO); + }); + } + + /// Test that migration skips when version is not 5 + #[test] + fn test_migrate_total_issuance_wrong_version() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to 4 (not 5) + StorageVersion::new(4).put::>(); + + // Run migration + let weight = migrate_total_issuance::(false); + + // Verify migration was skipped - only initial read occurred + let expected_weight = Test::DbWeight::get().reads(1); + assert_eq!(weight, expected_weight); + + // Verify version unchanged + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(4)); + }); + } + + /// Test migration with test flag enabled + #[test] + fn test_migrate_total_issuance_test_mode() { + new_test_ext(1).execute_with(|| { + // Setup: Set storage version to any value + StorageVersion::new(10).put::>(); + + // Run migration with test = true + let weight = migrate_total_issuance::(true); + + // Verify migration executed even with wrong version + assert!(weight != Weight::zero()); + + // Verify storage version updated to 6 + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(6)); + }); + } + + /// Test weight calculation includes all operations + #[test] + fn test_migrate_total_issuance_weight_calculation() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(5).put::>(); + + // Add multiple hotkeys to test weight scaling + let coldkey = U256::from(100); + for i in 1..=5 { + let hotkey = U256::from(i); + Owner::::insert(hotkey, coldkey); + TotalHotkeyStake::::insert(hotkey, TaoCurrency::from(1000)); + } + + // Run migration + let weight = migrate_total_issuance::(false); + + // Verify weight includes all reads and writes + // Expected: 1 version read + (5 Owner reads * 2 for stake) + 1 total_issuance read + 2 writes + assert!(weight.ref_time() > 0); + + let min_expected = Test::DbWeight::get().reads(1 + 10 + 1) + .saturating_add(Test::DbWeight::get().writes(2)); + + assert!(weight.ref_time() >= min_expected.ref_time()); + }); + } + + /// Test migration with empty Owner storage + #[test] + fn test_migrate_total_issuance_empty_owners() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(5).put::>(); + + // Don't add any owners + + // Run migration + let weight = migrate_total_issuance::(false); + + // Verify migration still completes + assert!(weight != Weight::zero()); + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(6)); + + // Total issuance should be set (even if just from balances) + let total_issuance = TotalIssuance::::get(); + assert!(total_issuance >= TaoCurrency::ZERO); + }); + } + + /// Test stake sum calculation with various stake amounts + #[test] + fn test_migrate_total_issuance_stake_aggregation() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(5).put::>(); + + let coldkey = U256::from(100); + + // Create hotkeys with different stake amounts + let stake_amounts = vec![ + TaoCurrency::from(100), + TaoCurrency::from(500), + TaoCurrency::from(1000), + TaoCurrency::ZERO, // Zero stake should also be handled + ]; + + for (i, stake) in stake_amounts.iter().enumerate() { + let hotkey = U256::from((i + 1) as u64); + Owner::::insert(hotkey, coldkey); + TotalHotkeyStake::::insert(hotkey, *stake); + } + + // Run migration + migrate_total_issuance::(false); + + // Verify total issuance calculated + let total_issuance = TotalIssuance::::get(); + + // Total should at least include the sum of stakes + let expected_stake_sum: TaoCurrency = stake_amounts.iter().fold(TaoCurrency::ZERO, |acc, s| acc.saturating_add(*s)); + assert!(total_issuance >= expected_stake_sum); + }); + } + + /// Test migration preserves existing behavior on conversion success + #[test] + fn test_migrate_total_issuance_conversion_success_path() { + new_test_ext(1).execute_with(|| { + StorageVersion::new(5).put::>(); + + // Setup minimal data + let hotkey = U256::from(1); + let coldkey = U256::from(100); + Owner::::insert(hotkey, coldkey); + TotalHotkeyStake::::insert(hotkey, TaoCurrency::from(500)); + + // Capture initial state + let initial_version = Pallet::::on_chain_storage_version(); + + // Run migration + let weight = migrate_total_issuance::(false); + + // Verify conversion succeeded and storage updated + assert!(weight > Test::DbWeight::get().reads(1)); + assert_eq!(Pallet::::on_chain_storage_version(), StorageVersion::new(6)); + assert!(initial_version < StorageVersion::new(6)); + }); + } +} + +// ERROR HANDLING DOCUMENTATION: +// +// Current error handling for conversion failure (line 76): +// - Logs error message via log::error! +// - Migration is aborted without updating storage version +// - This allows migration to be retried in future blocks +// +// Implications: +// 1. If total_balance cannot convert to u64, migration will retry every block +// 2. This could cause performance issues if conversion consistently fails +// 3. However, aborting is safer than proceeding with incorrect values +// +// Potential improvements (if needed in future): +// 1. Add a retry counter to prevent infinite retry loops +// 2. Consider updating storage version even on failure after N attempts +// 3. Add more detailed error context (e.g., the actual balance value that failed) +// 4. Emit an event to alert chain operators of persistent failures + /// Module containing deprecated storage format for LoadedEmission pub mod deprecated_loaded_emission_format {