Installation
Add the needed dependencies:
cargo add --dev anchor-litesvm litesvm litesvm-utils
What is anchor-litesvm?
The anchor-litesvm crate provides a simplified syntax similar to
anchor-client but without RPC overhead. It achieves 78% code reduction
compared to raw LiteSVM while maintaining type safety with Anchor types.
AnchorContext
- Production-compatible test context
- Same API patterns as anchor-client
- Manages LiteSVM instance, payer, and program
- Execute instructions without RPC overhead
Program API - Fluent instruction building - Type-safe account and argument handling - Familiar anchor-client syntax
Account Deserialization - Fetch and deserialize Anchor accounts - Automatic discriminator handling - Support for PDAs and custom layouts
Event Parsing
- Parse events from transaction logs
- Assert event emission
- Type-safe event deserialization
Quick Example
With Anchor 1.0, use declare_program! to generate client types from your
program's IDL. This macro creates client::accounts::* and client::args::*
modules for type-safe instruction building:
use anchor_litesvm::AnchorLiteSVM;use anchor_litesvm::{AssertionHelpers, TestHelpers};use anchor_lang::system_program;use solana_sdk::signature::{read_keypair_file, Signer};// Generate client types from your program's IDLanchor_lang::declare_program!(my_program);#[test]fn test_anchor_program() {// One-line setup — reads program keypair for the correct IDlet program_keypair = read_keypair_file("target/deploy/my_program-keypair.json").unwrap();let mut ctx = AnchorLiteSVM::build_with_program(program_keypair.pubkey(),include_bytes!("../target/deploy/my_program.so"),);// Create a funded account via TestHelpers on ctx.svmlet user = ctx.svm.create_funded_account(10_000_000_000).unwrap();// Derive PDAlet seed: u64 = 42;let pda = ctx.svm.get_pda(&[b"user", user.pubkey().as_ref(), &seed.to_le_bytes()],&program_keypair.pubkey(),);// Build instruction using generated client typeslet ix = ctx.program().accounts(my_program::client::accounts::Initialize {user: user.pubkey(),user_account: pda,system_program: system_program::ID,}).args(my_program::client::args::Initialize {seed,name: "test".to_string(),}).instruction().unwrap();// Execute and assert in one chainctx.execute_instruction(ix, &[&user]).unwrap().assert_success();// Fetch and deserialize the accountlet account: my_program::MyAccount = ctx.get_account(&pda).unwrap();assert_eq!(account.name, "test");}
declare_program!(my_program) reads the IDL from target/idl/my_program.json
at compile time and generates the client::accounts::* and client::args::*
modules. This requires building your program first.
Comparison: Raw LiteSVM vs anchor-litesvm
Before (Raw LiteSVM)
use litesvm::LiteSVM;use solana_keypair::Keypair;use solana_signer::Signer;use solana_program::instruction::{AccountMeta, Instruction};use solana_message::Message;use solana_transaction::Transaction;let mut svm = LiteSVM::new();svm.add_program(program_id, program_bytes).unwrap();let payer = Keypair::new();svm.airdrop(&payer.pubkey(), 10_000_000_000).unwrap();// Manually compute 8-byte discriminatorlet discriminator = {let mut hasher = sha2::Sha256::new();hasher.update(b"global:initialize");let result = hasher.finalize();result[..8].to_vec()};// Manually serialize args and build instructionlet mut data = discriminator;data.extend_from_slice(&borsh::to_vec(&args).unwrap());let accounts = vec![AccountMeta::new(user.pubkey(), true),AccountMeta::new(user_pda, false),AccountMeta::new_readonly(system_program::id(), false),];let ix = Instruction::new_with_bytes(program_id, &data, accounts);let tx = Transaction::new_signed_with_payer(&[ix],Some(&payer.pubkey()),&[&payer],svm.latest_blockhash(),);svm.send_transaction(tx).unwrap();// Manually deserialize with discriminator skiplet account_data = svm.get_account(&pda).unwrap().data;let account: UserAccount = UserAccount::try_deserialize(&mut &account_data[8..]).unwrap();
After (anchor-litesvm)
use anchor_litesvm::AnchorLiteSVM;anchor_lang::declare_program!(my_program);let mut ctx = AnchorLiteSVM::build_with_program(program_id, program_bytes);let user = ctx.svm.create_funded_account(10_000_000_000).unwrap();let ix = ctx.program().accounts(my_program::client::accounts::Initialize {user: user.pubkey(),user_account: user_pda,system_program: anchor_lang::system_program::ID,}).args(my_program::client::args::Initialize { name: "test".to_string() }).instruction().unwrap();ctx.execute_instruction(ix, &[&user]).unwrap().assert_success();let account: my_program::UserAccount = ctx.get_account(&user_pda).unwrap();
Key Components
AnchorLiteSVM Builder
| Method | Description |
|---|---|
new() | Creates a new builder instance |
with_payer(keypair) | Sets a custom payer keypair |
deploy_program(id, bytes) | Adds a program to deploy |
build() | Builds the AnchorContext |
build_with_program(id, bytes) | Convenience for single program |
build_with_programs(programs) | Deploy multiple programs |
AnchorContext
| Method | Description |
|---|---|
svm | Direct access to the underlying LiteSVM instance (public field) |
program_id | The program ID (public field) |
program() | Returns Program for instruction building |
payer() | Get the payer Keypair |
execute_instruction(ix, signers) | Execute a single instruction |
execute_instructions(ixs, signers) | Execute multiple instructions in one tx |
send_and_confirm_transaction(&tx) | Send a raw transaction |
get_account<T>(pubkey) | Fetch and deserialize an Anchor account |
get_account_unchecked<T>(pubkey) | Fetch without discriminator check |
create_funded_account(lamports) | Create and fund a new keypair |
airdrop(pubkey, lamports) | Airdrop SOL to an address |
latest_blockhash() | Get the current blockhash |
account_exists(pubkey) | Check if an account exists |
deploy_program(id, bytes) | Deploy an additional program (via ProgramTestExt) |
Program
| Method | Description |
|---|---|
accounts(accounts) | Set instruction accounts (any ToAccountMetas type) |
args(args) | Set instruction arguments (any InstructionData type) |
instruction() | Build the final Instruction |
id() | Get the program ID |
ctx.svm — TestHelpers & AssertionHelpers
ctx.svm is a public LiteSVM field with TestHelpers and AssertionHelpers
traits available via litesvm-utils:
| Method | Description |
|---|---|
ctx.svm.create_funded_account(lamports) | Create and fund a keypair |
ctx.svm.create_token_mint(authority, decimals) | Create an SPL token mint |
ctx.svm.create_associated_token_account(mint, owner) | Create an ATA |
ctx.svm.mint_to(mint, token_account, authority, amount) | Mint tokens |
ctx.svm.get_pda(seeds, program_id) | Derive a PDA address |
ctx.svm.get_pda_with_bump(seeds, program_id) | Derive PDA with bump seed |
ctx.svm.assert_token_balance(token_account, expected) | Assert token balance |
ctx.svm.assert_account_closed(pubkey) | Assert account was closed |
ctx.svm.assert_sol_balance(pubkey, expected) | Assert SOL balance |
Troubleshooting
Common Errors
| Error | Cause | Solution |
|---|---|---|
AccountNotFound | Account doesn't exist | Ensure account is created before fetching |
DiscriminatorMismatch | Wrong account type | Verify you're using the correct account struct |
DeserializationError | Invalid account data | Check account was initialized correctly |
| No programs added | Called build() without deploy_program() | Add at least one program before building |
| Missing client types | declare_program! not called | Run anchor build first to generate IDL, then call declare_program! |
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