lang: Add init_with_needed keyword

CHANGELOG.md

@@ -18,6 +18,7 @@ incremented for features.
 * ts: `Program<T>` can now be typed with an IDL type ([#795](https://github.com/project-serum/anchor/pull/795)).
 * lang: Add `mint::freeze_authority` keyword for mint initialization within `#[derive(Accounts)]` ([#835](https://github.com/project-serum/anchor/pull/835)).
 * lang: Add `AccountLoader` type for `zero_copy` accounts with support for CPI ([#792](https://github.com/project-serum/anchor/pull/792)).
+* lang: Add `#[account(init_if_needed)]` keyword for allowing one to invoke the same instruction even if the account was created already ([#906](https://github.com/project-serum/anchor/pull/906)).
 * lang: Add custom errors support for raw constraints ([#905](https://github.com/project-serum/anchor/pull/905)).
 
 ### Breaking

lang/syn/src/codegen/accounts/constraints.rs

@@ -316,7 +316,7 @@ fn generate_constraint_init_group(f: &Field, c: &ConstraintInitGroup) -> proc_ma
  }
  }
  };
- generate_init(f, seeds_with_nonce, payer, &c.space, &c.kind)
+ generate_init(f, c.if_needed, seeds_with_nonce, payer, &c.space, &c.kind)
 }
 
 fn generate_constraint_seeds(f: &Field, c: &ConstraintSeedsGroup) -> proc_macro2::TokenStream {
@@ -397,8 +397,10 @@ fn generate_constraint_associated_token(
  }
 }
 
+// `if_needed` is set if account allocation and initialization is optional.
 pub fn generate_init(
  f: &Field,
+ if_needed: bool,
  seeds_with_nonce: proc_macro2::TokenStream,
  payer: proc_macro2::TokenStream,
  space: &Option<Expr>,
@@ -407,6 +409,11 @@ pub fn generate_init(
  let field = &f.ident;
  let ty_decl = f.ty_decl();
  let from_account_info = f.from_account_info_unchecked(Some(kind));
+ let if_needed = if if_needed {
+ quote! {true}
+ } else {
+ quote! {false}
+ };
  match kind {
  InitKind::Token { owner, mint } => {
  let create_account = generate_create_account(
@@ -417,22 +424,25 @@ pub fn generate_init(
  );
  quote! {
  let #field: #ty_decl = {
- // Define payer variable.
- #payer
-
- // Create the account with the system program.
- #create_account
-
- // Initialize the token account.
- let cpi_program = token_program.to_account_info();
- let accounts = anchor_spl::token::InitializeAccount {
- account: #field.to_account_info(),
- mint: #mint.to_account_info(),
- authority: #owner.to_account_info(),
- rent: rent.to_account_info(),
- };
- let cpi_ctx = CpiContext::new(cpi_program, accounts);
- anchor_spl::token::initialize_account(cpi_ctx)?;
+ if !#if_needed || #field.to_account_info().owner == &anchor_lang::solana_program::system_program::ID {
+ // Define payer variable.
+ #payer
+
+ // Create the account with the system program.
+ #create_account
+
+ // Initialize the token account.
+ let cpi_program = token_program.to_account_info();
+ let accounts = anchor_spl::token::InitializeAccount {
+ account: #field.to_account_info(),
+ mint: #mint.to_account_info(),
+ authority: #owner.to_account_info(),
+ rent: rent.to_account_info(),
+ };
+ let cpi_ctx = CpiContext::new(cpi_program, accounts);
+ anchor_spl::token::initialize_account(cpi_ctx)?;
+ }
+
  let pa: #ty_decl = #from_account_info;
  pa
  };
@@ -441,20 +451,22 @@ pub fn generate_init(
  InitKind::AssociatedToken { owner, mint } => {
  quote! {
  let #field: #ty_decl = {
- #payer
-
- let cpi_program = associated_token_program.to_account_info();
- let cpi_accounts = anchor_spl::associated_token::Create {
- payer: payer.to_account_info(),
- associated_token: #field.to_account_info(),
- authority: #owner.to_account_info(),
- mint: #mint.to_account_info(),
- system_program: system_program.to_account_info(),
- token_program: token_program.to_account_info(),
- rent: rent.to_account_info(),
- };
- let cpi_ctx = CpiContext::new(cpi_program, cpi_accounts);
- anchor_spl::associated_token::create(cpi_ctx)?;
+ if !#if_needed || #field.to_account_info().owner == &anchor_lang::solana_program::system_program::ID {
+ #payer
+
+ let cpi_program = associated_token_program.to_account_info();
+ let cpi_accounts = anchor_spl::associated_token::Create {
+ payer: payer.to_account_info(),
+ associated_token: #field.to_account_info(),
+ authority: #owner.to_account_info(),
+ mint: #mint.to_account_info(),
+ system_program: system_program.to_account_info(),
+ token_program: token_program.to_account_info(),
+ rent: rent.to_account_info(),
+ };
+ let cpi_ctx = CpiContext::new(cpi_program, cpi_accounts);
+ anchor_spl::associated_token::create(cpi_ctx)?;
+ }
  let pa: #ty_decl = #from_account_info;
  pa
  };
@@ -477,20 +489,22 @@ pub fn generate_init(
  };
  quote! {
  let #field: #ty_decl = {
- // Define payer variable.
- #payer
-
- // Create the account with the system program.
- #create_account
-
- // Initialize the mint account.
- let cpi_program = token_program.to_account_info();
- let accounts = anchor_spl::token::InitializeMint {
- mint: #field.to_account_info(),
- rent: rent.to_account_info(),
- };
- let cpi_ctx = CpiContext::new(cpi_program, accounts);
- anchor_spl::token::initialize_mint(cpi_ctx, #decimals, &#owner.to_account_info().key, #freeze_authority)?;
+ if !#if_needed || #field.to_account_info().owner == &anchor_lang::solana_program::system_program::ID {
+ // Define payer variable.
+ #payer
+
+ // Create the account with the system program.
+ #create_account
+
+ // Initialize the mint account.
+ let cpi_program = token_program.to_account_info();
+ let accounts = anchor_spl::token::InitializeMint {
+ mint: #field.to_account_info(),
+ rent: rent.to_account_info(),
+ };
+ let cpi_ctx = CpiContext::new(cpi_program, accounts);
+ anchor_spl::token::initialize_mint(cpi_ctx, #decimals, &#owner.to_account_info().key, #freeze_authority)?;
+ }
  let pa: #ty_decl = #from_account_info;
  pa
  };
@@ -535,9 +549,11 @@ pub fn generate_init(
  generate_create_account(field, quote! {space}, owner, seeds_with_nonce);
  quote! {
  let #field = {
- #space
- #payer
- #create_account
+ if !#if_needed || #field.to_account_info().owner == &anchor_lang::solana_program::system_program::ID {
+ #space
+ #payer
+ #create_account
+ }
  let pa: #ty_decl = #from_account_info;
  pa
  };

lang/syn/src/lib.rs

@@ -594,7 +594,12 @@ impl Parse for ConstraintToken {
 }
 
 #[derive(Debug, Clone)]
-pub struct ConstraintInit {}
+pub struct ConstraintInit {
+ pub if_needed: bool,
+}
+
+#[derive(Debug, Clone)]
+pub struct ConstraintInitIfNeeded {}
 
 #[derive(Debug, Clone)]
 pub struct ConstraintZeroed {}
@@ -639,6 +644,7 @@ pub enum ConstraintRentExempt {
 
 #[derive(Debug, Clone)]
 pub struct ConstraintInitGroup {
+ pub if_needed: bool,
  pub seeds: Option<ConstraintSeedsGroup>,
  pub payer: Option<Expr>,
  pub space: Option<Expr>,

lang/syn/src/parser/accounts/constraints.rs

@@ -60,7 +60,14 @@ pub fn parse_token(stream: ParseStream) -> ParseResult<ConstraintToken> {
  let kw = ident.to_string();
 
  let c = match kw.as_str() {
- "init" => ConstraintToken::Init(Context::new(ident.span(), ConstraintInit {})),
+ "init" => ConstraintToken::Init(Context::new(
+ ident.span(),
+ ConstraintInit { if_needed: false },
+ )),
+ "init_if_needed" => ConstraintToken::Init(Context::new(
+ ident.span(),
+ ConstraintInit { if_needed: true },
+ )),
  "zero" => ConstraintToken::Zeroed(Context::new(ident.span(), ConstraintZeroed {})),
  "mut" => ConstraintToken::Mut(Context::new(ident.span(), ConstraintMut {})),
  "signer" => ConstraintToken::Signer(Context::new(ident.span(), ConstraintSigner {})),
@@ -518,7 +525,8 @@ impl<'ty> ConstraintGroupBuilder<'ty> {
  _ => None,
  };
  Ok(ConstraintGroup {
- init: init.as_ref().map(|_| Ok(ConstraintInitGroup {
+ init: init.as_ref().map(|i| Ok(ConstraintInitGroup {
+ if_needed: i.if_needed,
  seeds: seeds.clone(),
  payer: into_inner!(payer.clone()).map(|a| a.target),
  space: space.clone().map(|s| s.space.clone()),

tests/misc/programs/misc/src/context.rs

@@ -244,3 +244,11 @@ pub struct TestEmptySeedsConstraint<'info> {
  #[account(seeds = [], bump)]
  pub pda: AccountInfo<'info>,
 }
+
+#[derive(Accounts)]
+pub struct TestInitIfNeeded<'info> {
+ #[account(init_if_needed, payer = payer)]
+ pub data: Account<'info, DataU16>,
+ pub payer: Signer<'info>,
+ pub system_program: Program<'info, System>,
+}

tests/misc/programs/misc/src/lib.rs

@@ -184,4 +184,9 @@ pub mod misc {
  pub fn test_empty_seeds_constraint(ctx: Context<TestEmptySeedsConstraint>) -> ProgramResult {
  Ok(())
  }
+
+ pub fn test_init_if_needed(ctx: Context<TestInitIfNeeded>, data: u16) -> ProgramResult {
+ ctx.accounts.data.data = data;
+ Ok(())
+ }
 }

tests/misc/tests/misc.js

@@ -652,8 +652,8 @@ describe("misc", () => {
  accounts: {
  token: associatedToken,
  mint: mint.publicKey,
- wallet: program.provider.wallet.publicKey
- }
+ wallet: program.provider.wallet.publicKey,
+ },
  });
 
  await assert.rejects(
@@ -662,8 +662,8 @@ describe("misc", () => {
  accounts: {
  token: associatedToken,
  mint: mint.publicKey,
- wallet: anchor.web3.Keypair.generate().publicKey
- }
+ wallet: anchor.web3.Keypair.generate().publicKey,
+ },
  });
  },
  (err) => {
@@ -735,30 +735,31 @@ describe("misc", () => {
  ]);
  // Call for multiple kinds of .all.
  const allAccounts = await program.account.dataWithFilter.all();
- const allAccountsFilteredByBuffer =
- await program.account.dataWithFilter.all(
- program.provider.wallet.publicKey.toBuffer()
- );
- const allAccountsFilteredByProgramFilters1 =
- await program.account.dataWithFilter.all([
+ const allAccountsFilteredByBuffer = await program.account.dataWithFilter.all(
+ program.provider.wallet.publicKey.toBuffer()
+ );
+ const allAccountsFilteredByProgramFilters1 = await program.account.dataWithFilter.all(
+ [
  {
  memcmp: {
  offset: 8,
  bytes: program.provider.wallet.publicKey.toBase58(),
  },
  },
  { memcmp: { offset: 40, bytes: filterable1.toBase58() } },
- ]);
- const allAccountsFilteredByProgramFilters2 =
- await program.account.dataWithFilter.all([
+ ]
+ );
+ const allAccountsFilteredByProgramFilters2 = await program.account.dataWithFilter.all(
+ [
  {
  memcmp: {
  offset: 8,
  bytes: program.provider.wallet.publicKey.toBase58(),
  },
  },
  { memcmp: { offset: 40, bytes: filterable2.toBase58() } },
- ]);
+ ]
+ );
  // Without filters there should be 4 accounts.
  assert.equal(allAccounts.length, 4);
  // Filtering by main wallet there should be 3 accounts.
@@ -772,32 +773,66 @@ describe("misc", () => {
  });
 
  it("Can use pdas with empty seeds", async () => {
- const [pda, bump] = await PublicKey.findProgramAddress([], program.programId);
+ const [pda, bump] = await PublicKey.findProgramAddress(
+ [],
+ program.programId
+ );
 
  await program.rpc.testInitWithEmptySeeds({
  accounts: {
  pda: pda,
  authority: program.provider.wallet.publicKey,
- systemProgram: anchor.web3.SystemProgram.programId
- }
+ systemProgram: anchor.web3.SystemProgram.programId,
+ },
  });
  await program.rpc.testEmptySeedsConstraint({
  accounts: {
- pda: pda
- }
+ pda: pda,
+ },
  });
 
- const [pda2, bump2] = await PublicKey.findProgramAddress(["non-empty"], program.programId);
+ const [pda2, bump2] = await PublicKey.findProgramAddress(
+ ["non-empty"],
+ program.programId
+ );
  await assert.rejects(
  program.rpc.testEmptySeedsConstraint({
  accounts: {
- pda: pda2
- }
+ pda: pda2,
+ },
  }),
  (err) => {
  assert.equal(err.code, 146);
  return true;
  }
  );
  });
+
+ const ifNeededAcc = anchor.web3.Keypair.generate();
+
+ it("Can init if needed a new account", async () => {
+ await program.rpc.testInitIfNeeded(1, {
+ accounts: {
+ data: ifNeededAcc.publicKey,
+ systemProgram: anchor.web3.SystemProgram.programId,
+ payer: program.provider.wallet.publicKey,
+ },
+ signers: [ifNeededAcc],
+ });
+ const account = await program.account.dataU16.fetch(ifNeededAcc.publicKey);
+ assert.ok(account.data, 1);
+ });
+
+ it("Can init if needed a previously created account", async () => {
+ await program.rpc.testInitIfNeeded(3, {
+ accounts: {
+ data: ifNeededAcc.publicKey,
+ systemProgram: anchor.web3.SystemProgram.programId,
+ payer: program.provider.wallet.publicKey,
+ },
+ signers: [ifNeededAcc],
+ });
+ const account = await program.account.dataU16.fetch(ifNeededAcc.publicKey);
+ assert.ok(account.data, 3);
+ });
 });