lang: Deprecate AccountInfo usage with compile-time warning in Accounts macro (solana-foundation#3854)

* Deprecate AccountInfo usage with compile-time warning in Accounts macro

* cargo fmt

Author: bergabman

lang/src/lib.rs

@@ -173,6 +173,12 @@ pub use anchor_attribute_program::interface;
 
 pub type Result<T> = std::result::Result<T, error::Error>;
 
+// Deprecated message for AccountInfo usage in Accounts struct
+#[deprecated(
+    note = "Use `UncheckedAccount` instead of `AccountInfo` for safer unchecked accounts."
+)]
+pub fn deprecated_account_info_usage() {}
+
 /// A data structure of validated accounts that can be deserialized from the
 /// input to a Solana program. Implementations of this trait should perform any
 /// and all requisite constraint checks on accounts to ensure the accounts

lang/src/system_program.rs

@@ -1,3 +1,5 @@
+// Avoiding AccountInfo deprecated msg in anchor context
+#![allow(deprecated)]
 use crate::prelude::*;
 use crate::solana_program::pubkey::Pubkey;
 

lang/src/vec.rs

@@ -1,3 +1,5 @@
+// Avoiding AccountInfo deprecated msg in anchor context
+#![allow(deprecated)]
 use crate::solana_program::account_info::AccountInfo;
 use crate::solana_program::instruction::AccountMeta;
 use crate::solana_program::pubkey::Pubkey;

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

@@ -1,6 +1,6 @@
 use crate::codegen::accounts::{bumps, constraints, generics, ParsedGenerics};
-use crate::{AccountField, AccountsStruct};
-use quote::quote;
+use crate::{AccountField, AccountsStruct, Ty};
+use quote::{quote, quote_spanned};
 use syn::Expr;
 
 // Generates the `Accounts` trait implementation.
@@ -68,11 +68,21 @@ pub fn generate(accs: &AccountsStruct) -> proc_macro2::TokenStream {
                     } else {
                         let name = f.ident.to_string();
                         let typed_name = f.typed_ident();
+
+                        // Generate the deprecation call if it is an AccountInfo
+                        let warning = if matches!(f.ty, Ty::AccountInfo) {
+                            quote_spanned! { f.ty_span =>
+                                ::anchor_lang::deprecated_account_info_usage();
+                            }
+                        } else {
+                            quote! {}
+                        };
                         quote! {
                             #[cfg(feature = "anchor-debug")]
                             ::solana_program::log::sol_log(stringify!(#typed_name));
                             let #typed_name = anchor_lang::Accounts::try_accounts(__program_id, __accounts, __ix_data, __bumps, __reallocs)
                                 .map_err(|e| e.with_account_name(#name))?;
+                            #warning
                         }
                     }
                 }

lang/syn/src/lib.rs

@@ -282,6 +282,7 @@ pub struct Field {
     pub constraints: ConstraintGroup,
     pub ty: Ty,
     pub is_optional: bool,
+    pub ty_span: Span,
     /// IDL Doc comment
     pub docs: Option<Vec<String>>,
 }

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

@@ -315,6 +315,7 @@ pub fn parse_account_field(f: &syn::Field) -> ParseResult<AccountField> {
                 ty,
                 is_optional,
                 constraints: account_constraints,
+                ty_span: f.ty.span(),
                 docs,
             })
         }

lang/tests/generics_test.rs

@@ -1,4 +1,5 @@
-#![allow(dead_code)]
+// Avoiding AccountInfo deprecated msg in anchor context
+#![allow(dead_code, deprecated)]
 
 use anchor_lang::prelude::borsh::maybestd::io::Write;
 use anchor_lang::prelude::*;

spl/src/associated_token.rs

@@ -1,3 +1,5 @@
+// Avoiding AccountInfo deprecated msg in anchor context
+#![allow(deprecated)]
 use anchor_lang::solana_program::account_info::AccountInfo;
 use anchor_lang::solana_program::pubkey::Pubkey;
 use anchor_lang::Result;

spl/src/token.rs

@@ -1,3 +1,5 @@
+// Avoiding AccountInfo deprecated msg in anchor context
+#![allow(deprecated)]
 use anchor_lang::solana_program::account_info::AccountInfo;
 use anchor_lang::solana_program::program_pack::Pack;
 use anchor_lang::solana_program::pubkey::Pubkey;

spl/src/token_2022.rs

@@ -1,3 +1,5 @@
+// Avoiding AccountInfo deprecated msg in anchor context
+#![allow(deprecated)]
 use anchor_lang::solana_program::account_info::AccountInfo;
 use anchor_lang::solana_program::pubkey::Pubkey;
 use anchor_lang::Result;