Time & Sysvars

Methods for manipulating time and accessing system variables.

Enable sysvars first with client.svm.withSysvars() before accessing sysvar methods.

Clock Manipulation

warpToSlot

warpToSlot(slot: bigint): LiteSVM

Advance the clock to a specific slot.

client.svm.withSysvars();

// Check current slot
const before = client.svm.getClock();
console.log("Current slot:", before.slot);

// Warp forward
client.svm.warpToSlot(10000n);

const after = client.svm.getClock();
console.log("New slot:", after.slot);

getClock

getClock(): Clock

Get the current clock sysvar values.

const clock = client.svm.getClock();

console.log("Slot:", clock.slot);
console.log("Epoch:", clock.epoch);
console.log("Unix timestamp:", clock.unixTimestamp);
console.log("Epoch start timestamp:", clock.epochStartTimestamp);
console.log("Leader schedule epoch:", clock.leaderScheduleEpoch);

setClock

setClock(clock: Clock): LiteSVM

Overwrite the clock sysvar. Get the clock, mutate its fields, then write it back. Use this when you need precise control over multiple clock fields — for example, setting the epoch or unix timestamp, which warpToSlot does not update.

const clock = client.svm.getClock();
clock.slot = 1000n;
clock.epoch = 10n;
clock.unixTimestamp = 1735689600n;
client.svm.setClock(clock);

warpToSlot only updates slot. Use setClock when your program reads epoch or unix_timestamp from the Clock sysvar.

Clock Properties

Property	Type	Description
`slot`	`bigint`	Current slot number
`epoch`	`bigint`	Current epoch number
`unixTimestamp`	`bigint`	Unix timestamp in seconds
`epochStartTimestamp`	`bigint`	Start of current epoch
`leaderScheduleEpoch`	`bigint`	Leader schedule epoch

Rent

getRent

getRent(): Rent

Get the rent sysvar.

const rent = client.svm.getRent();

console.log("Lamports per byte-year:", rent.lamportsPerByteYear);
console.log("Exemption threshold:", rent.exemptionThreshold);
console.log("Burn percent:", rent.burnPercent);

minimumBalanceForRentExemption

minimumBalanceForRentExemption(dataLen: bigint): bigint

Calculate the minimum lamports needed for rent exemption.

// Calculate for different data sizes
for (const size of [0n, 100n, 1000n]) {
  const min = client.svm.minimumBalanceForRentExemption(size);
  console.log(`${size} bytes: ${min} lamports`);
}

Epoch Schedule

getEpochSchedule

getEpochSchedule(): EpochSchedule

Get the epoch schedule sysvar.

const epochSchedule = client.svm.getEpochSchedule();

console.log("Slots per epoch:", epochSchedule.slotsPerEpoch);
console.log(
  "Leader schedule slot offset:",
  epochSchedule.leaderScheduleSlotOffset
);
console.log("Warmup:", epochSchedule.warmup);
console.log("First normal epoch:", epochSchedule.firstNormalEpoch);
console.log("First normal slot:", epochSchedule.firstNormalSlot);

Epoch Rewards

getEpochRewards

getEpochRewards(): EpochRewards

Get the epoch rewards sysvar.

const rewards = client.svm.getEpochRewards();

console.log("Active:", rewards.active);
console.log("Total rewards:", rewards.totalRewards);
console.log("Distributed rewards:", rewards.distributedRewards);
console.log("Total points:", rewards.totalPoints);
console.log("Num partitions:", rewards.numPartitions);
console.log(
  "Distribution starting block height:",
  rewards.distributionStartingBlockHeight
);

Slot Information

getSlotHashes

getSlotHashes(): SlotHash[]

Get recent slot hashes.

const slotHashes = client.svm.getSlotHashes();

console.log("Slot hashes count:", slotHashes.length);
if (slotHashes.length > 0) {
  console.log("First hash:", {
    slot: slotHashes[0].slot,
    hash: slotHashes[0].hash
  });
}

getSlotHistory

getSlotHistory(): SlotHistory

Get the slot history.

const slotHistory = client.svm.getSlotHistory();
console.log("Next slot:", slotHistory.nextSlot);

getLastRestartSlot / setLastRestartSlot

getLastRestartSlot(): bigint
setLastRestartSlot(slot: bigint): LiteSVM

Get or set the last restart slot.

const lastRestart = client.svm.getLastRestartSlot();
console.log("Last restart slot:", lastRestart);

client.svm.setLastRestartSlot(500n);

Stake History

getStakeHistory

getStakeHistory(): StakeHistory

Get the stake history.

const stakeHistory = client.svm.getStakeHistory();
// Returns array of { epoch, entry: { effective, activating, deactivating } }

Testing Time-Dependent Logic

Use warpToSlot to test time-dependent program behavior:

import { createClient, generateKeyPairSigner } from "@solana/kit";
import { litesvm } from "@solana/kit-plugin-litesvm";
import { signer } from "@solana/kit-plugin-signer";

async function testTimeLockedVault() {
  const mySigner = await generateKeyPairSigner();
  const client = createClient().use(signer(mySigner)).use(litesvm());
  client.svm.withSysvars();

  const unlockSlot = 10000n;

  // Setup: Create time-locked account
  // ... set up your account state ...

  // Test 1: Try to withdraw before unlock (should fail)
  const beforeClock = client.svm.getClock();
  console.log("Current slot:", beforeClock.slot);
  // ... attempt withdrawal, expect failure ...

  // Warp time forward past unlock slot
  client.svm.warpToSlot(unlockSlot + 1n);

  // Test 2: Try to withdraw after unlock (should succeed)
  const afterClock = client.svm.getClock();
  console.log("New slot:", afterClock.slot);
  // ... attempt withdrawal, expect success ...
}

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