Time Manipulation
warp_to_slot
pub fn warp_to_slot(&mut self, slot: u64)
Jump to a specific slot. Only forward time travel is supported.
// Get current slotlet clock: Clock = svm.get_sysvar();let current_slot = clock.slot;// Jump forward 100 slotssvm.warp_to_slot(current_slot + 100);// Verifylet new_clock: Clock = svm.get_sysvar();assert_eq!(new_clock.slot, current_slot + 100);
Manual Clock Manipulation
use solana_sdk::clock::Clock;// Read clocklet mut clock: Clock = svm.get_sysvar();// Modify fieldsclock.slot = 1000;clock.epoch = 10;clock.unix_timestamp = 1735689600;// Write backsvm.set_sysvar(&clock);
Use warp_to_slot() for most time manipulation. Use manual clock modification
only when you need precise control over multiple fields.
Sysvars
get_sysvar
pub fn get_sysvar<T: Sysvar>(&self) -> T
Read sysvar value.
use solana_sdk::clock::Clock;use solana_sdk::rent::Rent;use solana_sdk::epoch_schedule::EpochSchedule;let clock: Clock = svm.get_sysvar();let rent: Rent = svm.get_sysvar();let epoch_schedule: EpochSchedule = svm.get_sysvar();
set_sysvar
pub fn set_sysvar<T: Sysvar>(&mut self, sysvar: &T)
Write sysvar value.
use solana_sdk::rent::Rent;let rent = Rent {lamports_per_byte_year: 3480,exemption_threshold: 2.0,burn_percent: 50,};svm.set_sysvar(&rent);
Common Sysvars
Clock
use solana_sdk::clock::Clock;let clock: Clock = svm.get_sysvar();println!("Slot: {}", clock.slot);println!("Timestamp: {}", clock.unix_timestamp);println!("Epoch: {}", clock.epoch);
Rent
use solana_sdk::rent::Rent;let rent: Rent = svm.get_sysvar();let min_balance = rent.minimum_balance(data_len);
Epoch Schedule
use solana_sdk::epoch_schedule::EpochSchedule;let schedule: EpochSchedule = svm.get_sysvar();println!("Slots per epoch: {}", schedule.slots_per_epoch);
Stake History
use solana_sdk::stake_history::{StakeHistory, StakeHistoryEntry};let mut stake_history = StakeHistory::default();stake_history.add(0, // epochStakeHistoryEntry {effective: 1_000_000,activating: 0,deactivating: 0,},);svm.set_sysvar(&stake_history);
Time-Based Testing Patterns
Test Slot-Based Features
let mut svm = LiteSVM::new();// Get starting slotlet start_slot = svm.get_sysvar::<Clock>().slot;// Try action before unlock slot (should fail)let result = call_locked_program(&mut svm);assert!(result.is_err());// Warp to unlock slotsvm.warp_to_slot(start_slot + 1000);// Now it should succeedlet result = call_locked_program(&mut svm);assert!(result.is_ok());
Test Timestamp-Based Features
let mut svm = LiteSVM::new();// Get current timestamplet clock: Clock = svm.get_sysvar();let current_time = clock.unix_timestamp;// Warp forward 1 hour (3600 seconds)// Slots roughly correspond to ~0.4 seconds on Solanalet target_slot = clock.slot + (3600.0 / 0.4) as u64;svm.warp_to_slot(target_slot);// Verify timestamp increasedlet new_clock: Clock = svm.get_sysvar();assert!(new_clock.unix_timestamp >= current_time + 3600);
Test Vesting Schedules
// Setup vesting with 100 slot periodlet vesting_period = 100;let start_slot = svm.get_sysvar::<Clock>().slot;// Test before vesting completeslet result = claim_vested_tokens(&mut svm);assert!(result.is_err()); // Too early// Warp past vesting periodsvm.warp_to_slot(start_slot + vesting_period + 1);// Now claim should succeedlet result = claim_vested_tokens(&mut svm);assert!(result.is_ok());
Common Use Cases
- Vesting schedules
- Time-locked withdrawals
- Stake/unstake cooldown periods
- Auction end times
- Rental periods
- Epoch-based rewards
Important Notes
- Forward only - You can only warp forward in time, not backward
- Slot to time - Slots roughly correspond to ~0.4 seconds on Solana mainnet
- Clock sysvar - Always updated when using
warp_to_slot() - No automatic updates - Unlike real validators, time doesn't advance automatically between transactions
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