lang, examples: UncheckedAccount and Cfo updates (#745)

README.md

@@ -65,18 +65,15 @@ mod counter {
 pub struct Initialize<'info> {
     #[account(init, payer = authority, space = 48)]
     pub counter: Account<'info, Counter>,
-    #[account(signer)]
-    pub authority: AccountInfo<'info>,
-    #[account(address = system_program::ID)]
-    pub system_program: AccountInfo<'info>,
+    pub authority: Signer<'info>,
+    pub system_program: Program<'info, System>,
 }
 
 #[derive(Accounts)]
 pub struct Increment<'info> {
     #[account(mut, has_one = authority)]
     pub counter: Account<'info, Counter>,
-    #[account(signer)]
-    pub authority: AccountInfo<'info>,
+    pub authority: Signer<'info>,
 }
 
 #[account]

lang/src/lib.rs

@@ -50,6 +50,7 @@ mod signer;
 pub mod state;
 mod system_program;
 mod sysvar;
+mod unchecked_account;
 mod vec;
 
 pub use crate::account::Account;
@@ -74,6 +75,7 @@ pub use crate::signer::Signer;
 pub use crate::state::ProgramState;
 pub use crate::system_program::System;
 pub use crate::sysvar::Sysvar;
+pub use crate::unchecked_account::UncheckedAccount;
 pub use anchor_attribute_access_control::access_control;
 pub use anchor_attribute_account::{account, declare_id, zero_copy};
 pub use anchor_attribute_error::error;
@@ -247,6 +249,7 @@ pub mod prelude {
         state, zero_copy, Account, AccountDeserialize, AccountSerialize, Accounts, AccountsExit,
         AnchorDeserialize, AnchorSerialize, Context, CpiContext, Key, Loader, Owner, Program,
         ProgramAccount, Signer, System, Sysvar, ToAccountInfo, ToAccountInfos, ToAccountMetas,
+        UncheckedAccount,
     };
 
     #[allow(deprecated)]

lang/src/unchecked_account.rs

@@ -0,0 +1,77 @@
+use crate::error::ErrorCode;
+use crate::{Accounts, AccountsExit, Key, ToAccountInfo, ToAccountInfos, ToAccountMetas};
+use solana_program::account_info::AccountInfo;
+use solana_program::entrypoint::ProgramResult;
+use solana_program::instruction::AccountMeta;
+use solana_program::program_error::ProgramError;
+use solana_program::pubkey::Pubkey;
+use std::ops::Deref;
+
+/// Explicit wrapper for AccountInfo types.
+#[derive(Clone)]
+pub struct UncheckedAccount<'info>(AccountInfo<'info>);
+
+impl<'info> UncheckedAccount<'info> {
+    pub fn try_from(acc_info: AccountInfo<'info>) -> Self {
+        Self(acc_info)
+    }
+}
+
+impl<'info> Accounts<'info> for UncheckedAccount<'info> {
+    fn try_accounts(
+        _program_id: &Pubkey,
+        accounts: &mut &[AccountInfo<'info>],
+        _ix_data: &[u8],
+    ) -> Result<Self, ProgramError> {
+        if accounts.is_empty() {
+            return Err(ErrorCode::AccountNotEnoughKeys.into());
+        }
+        let account = &accounts[0];
+        *accounts = &accounts[1..];
+        Ok(UncheckedAccount(account.clone()))
+    }
+}
+
+impl<'info> ToAccountMetas for UncheckedAccount<'info> {
+    fn to_account_metas(&self, is_signer: Option<bool>) -> Vec<AccountMeta> {
+        let is_signer = is_signer.unwrap_or(self.is_signer);
+        let meta = match self.is_writable {
+            false => AccountMeta::new_readonly(*self.key, is_signer),
+            true => AccountMeta::new(*self.key, is_signer),
+        };
+        vec![meta]
+    }
+}
+
+impl<'info> ToAccountInfos<'info> for UncheckedAccount<'info> {
+    fn to_account_infos(&self) -> Vec<AccountInfo<'info>> {
+        vec![self.0.clone()]
+    }
+}
+
+impl<'info> ToAccountInfo<'info> for UncheckedAccount<'info> {
+    fn to_account_info(&self) -> AccountInfo<'info> {
+        self.0.clone()
+    }
+}
+
+impl<'info> AccountsExit<'info> for UncheckedAccount<'info> {
+    fn exit(&self, _program_id: &Pubkey) -> ProgramResult {
+        // no-op
+        Ok(())
+    }
+}
+
+impl<'info> Key for UncheckedAccount<'info> {
+    fn key(&self) -> Pubkey {
+        *self.key
+    }
+}
+
+impl<'info> Deref for UncheckedAccount<'info> {
+    type Target = AccountInfo<'info>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}

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

@@ -143,7 +143,7 @@ pub fn generate_constraint_init(f: &Field, c: &ConstraintInitGroup) -> proc_macr
 pub fn generate_constraint_zeroed(f: &Field, _c: &ConstraintZeroed) -> proc_macro2::TokenStream {
     let field = &f.ident;
     let ty_decl = f.ty_decl();
-    let from_account_info = f.from_account_info(None);
+    let from_account_info = f.from_account_info_unchecked(None);
     quote! {
         let #field: #ty_decl = {
             let mut __data: &[u8] = &#field.try_borrow_data()?;
@@ -374,7 +374,7 @@ pub fn generate_init(
 ) -> proc_macro2::TokenStream {
     let field = &f.ident;
     let ty_decl = f.ty_decl();
-    let from_account_info = f.from_account_info(Some(kind));
+    let from_account_info = f.from_account_info_unchecked(Some(kind));
     match kind {
         InitKind::Token { owner, mint } => {
             let create_account = generate_create_account(
@@ -401,7 +401,7 @@ pub fn generate_init(
                     };
                     let cpi_ctx = CpiContext::new(cpi_program, accounts);
                     anchor_spl::token::initialize_account(cpi_ctx)?;
-                    let mut pa: #ty_decl = #from_account_info;
+                    let pa: #ty_decl = #from_account_info;
                     pa
                 };
             }
@@ -429,7 +429,7 @@ pub fn generate_init(
                     };
                     let cpi_ctx = CpiContext::new(cpi_program, accounts);
                     anchor_spl::token::initialize_mint(cpi_ctx, #decimals, &#owner.to_account_info().key, None)?;
-                    let mut pa: #ty_decl = #from_account_info;
+                    let pa: #ty_decl = #from_account_info;
                     pa
                 };
             }
@@ -476,7 +476,7 @@ pub fn generate_init(
                     #space
                     #payer
                     #create_account
-                    let mut pa: #ty_decl = #from_account_info;
+                    let pa: #ty_decl = #from_account_info;
                     pa
                 };
             }

lang/syn/src/lib.rs

@@ -178,6 +178,9 @@ impl Field {
             Ty::AccountInfo => quote! {
                 AccountInfo
             },
+            Ty::UncheckedAccount => quote! {
+                UncheckedAccount
+            },
             Ty::Signer => quote! {
                 Signer
             },
@@ -217,11 +220,14 @@ impl Field {
 
     // TODO: remove the option once `CpiAccount` is completely removed (not
     //       just deprecated).
-    pub fn from_account_info(&self, kind: Option<&InitKind>) -> proc_macro2::TokenStream {
+    pub fn from_account_info_unchecked(&self, kind: Option<&InitKind>) -> proc_macro2::TokenStream {
         let field = &self.ident;
         let container_ty = self.container_ty();
         match &self.ty {
             Ty::AccountInfo => quote! { #field.to_account_info() },
+            Ty::UncheckedAccount => {
+                quote! { UncheckedAccount::try_from(#field.to_account_info()) }
+            }
             Ty::Account(AccountTy { boxed, .. }) => {
                 if *boxed {
                     quote! {
@@ -276,6 +282,7 @@ impl Field {
             Ty::ProgramState(_) => quote! { anchor_lang::ProgramState },
             Ty::Program(_) => quote! { anchor_lang::Program },
             Ty::AccountInfo => quote! {},
+            Ty::UncheckedAccount => quote! {},
             Ty::Signer => quote! {},
         }
     }
@@ -286,6 +293,9 @@ impl Field {
             Ty::AccountInfo => quote! {
                 AccountInfo
             },
+            Ty::UncheckedAccount => quote! {
+                UncheckedAccount
+            },
             Ty::Signer => quote! {
                 Signer
             },
@@ -360,6 +370,7 @@ pub struct CompositeField {
 #[derive(Debug, PartialEq)]
 pub enum Ty {
     AccountInfo,
+    UncheckedAccount,
     ProgramState(ProgramStateTy),
     CpiState(CpiStateTy),
     ProgramAccount(ProgramAccountTy),

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

@@ -18,7 +18,6 @@ pub fn parse(
         }
     }
     let account_constraints = constraints.build()?;
-
     let mut constraints = ConstraintGroupBuilder::new(f_ty);
     for attr in f.attrs.iter().filter(is_instruction) {
         if !has_instruction_api {

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

@@ -71,6 +71,7 @@ fn is_field_primitive(f: &syn::Field) -> ParseResult<bool> {
             | "CpiAccount"
             | "Sysvar"
             | "AccountInfo"
+            | "UncheckedAccount"
             | "CpiState"
             | "Loader"
             | "Account"
@@ -92,6 +93,7 @@ fn parse_ty(f: &syn::Field) -> ParseResult<Ty> {
         "CpiAccount" => Ty::CpiAccount(parse_cpi_account(&path)?),
         "Sysvar" => Ty::Sysvar(parse_sysvar(&path)?),
         "AccountInfo" => Ty::AccountInfo,
+        "UncheckedAccount" => Ty::UncheckedAccount,
         "Loader" => Ty::Loader(parse_program_account_zero_copy(&path)?),
         "Account" => Ty::Account(parse_account_ty(&path)?),
         "Program" => Ty::Program(parse_program_ty(&path)?),

tests/cfo/programs/cfo/Cargo.toml

@@ -18,7 +18,8 @@ test = []
 [dependencies]
 anchor-lang = { path = "../../../../lang" }
 anchor-spl = { path = "../../../../spl" }
-spl-token = { version ="3.1.1", features = ["no-entrypoint"] }
+spl-token = { version = "3.1.1", features = ["no-entrypoint"] }
 swap = { path = "../../deps/swap/programs/swap", features = ["cpi"] }
+serum_dex = { path = "../../deps/serum-dex/dex", features = ["no-entrypoint"] }
 registry = { path = "../../deps/stake/programs/registry", features = ["cpi"] }
 lockup = { path = "../../deps/stake/programs/lockup", features = ["cpi"] }