Add test to enforce that program id account info for CPI is optional (#22069)

* Update tests to demonstrate that program id account info for CPI is optional

* Clean up comments that say that program id account info is required

docs/src/developing/programming-model/calling-between-programs.md

@@ -57,9 +57,7 @@ given instruction to the `token` program via the instruction's `program_id`
 field.
 
 Note that `invoke` requires the caller to pass all the accounts required by the
-instruction being invoked. This means that both the executable account (the
+instruction being invoked, except for the executable account (the `program_id`).
-ones that matches the instruction's program id) and the accounts passed to the
-instruction processor.
 
 Before invoking `pay()`, the runtime must ensure that `acme` didn't modify any
 accounts owned by `token`. It does this by applying the runtime's policy to the

programs/bpf/rust/instruction_introspection/src/lib.rs

@@ -54,7 +54,7 @@ fn process_instruction(
                 &[instruction_data[0], instruction_data[1], 1],
                 vec![AccountMeta::new_readonly(instructions::id(), false)],
             ),
-            accounts,
+            &[instructions_account.clone()],
         )?;
     }
 

programs/bpf/rust/invoke_and_return/src/lib.rs

@@ -14,7 +14,6 @@ fn process_instruction(
     instruction_data: &[u8],
 ) -> ProgramResult {
     let to_call = accounts[0].key;
-    let infos = accounts;
     let instruction = Instruction {
         accounts: accounts[1..]
             .iter()
@@ -27,5 +26,7 @@ fn process_instruction(
         data: instruction_data.to_owned(),
         program_id: *to_call,
     };
-    invoke(&instruction, infos)
+    // program id account is not required for invocations if the
+    // program id is not one of the instruction account metas.
+    invoke(&instruction, &accounts[1..])
 }

programs/bpf/rust/upgradeable/src/lib.rs

@@ -8,13 +8,12 @@ use solana_program::{
 
 entrypoint!(process_instruction);
 fn process_instruction(
-    program_id: &Pubkey,
+    _program_id: &Pubkey,
     accounts: &[AccountInfo],
     _instruction_data: &[u8],
 ) -> ProgramResult {
     msg!("Upgradeable program");
-    assert_eq!(accounts.len(), 2);
+    assert_eq!(accounts.len(), 1);
-    assert_eq!(accounts[0].key, program_id);
+    assert_eq!(*accounts[0].key, clock::id());
-    assert_eq!(*accounts[1].key, clock::id());
     Err(42.into())
 }

programs/bpf/rust/upgraded/src/lib.rs

@@ -8,13 +8,12 @@ use solana_program::{
 
 entrypoint!(process_instruction);
 fn process_instruction(
-    program_id: &Pubkey,
+    _program_id: &Pubkey,
     accounts: &[AccountInfo],
     _instruction_data: &[u8],
 ) -> ProgramResult {
     msg!("Upgraded program");
-    assert_eq!(accounts.len(), 2);
+    assert_eq!(accounts.len(), 1);
-    assert_eq!(accounts[0].key, program_id);
+    assert_eq!(*accounts[0].key, clock::id());
-    assert_eq!(*accounts[1].key, clock::id());
     Err(43.into())
 }

programs/bpf/tests/programs.rs

@@ -1450,8 +1450,8 @@ fn test_program_bpf_instruction_introspection() {
 
     // Passing transaction
     let account_metas = vec![
-        AccountMeta::new(program_id, false),
+        AccountMeta::new_readonly(program_id, false),
-        AccountMeta::new(sysvar::instructions::id(), false),
+        AccountMeta::new_readonly(sysvar::instructions::id(), false),
     ];
     let instruction0 = Instruction::new_with_bytes(program_id, &[0u8, 0u8], account_metas.clone());
     let instruction1 = Instruction::new_with_bytes(program_id, &[0u8, 1u8], account_metas.clone());
@@ -1743,7 +1743,6 @@ fn test_program_bpf_upgrade() {
         program_id,
         &[0],
         vec![
-            AccountMeta::new(program_id.clone(), false),
             AccountMeta::new(clock::id(), false),
         ],
     );
@@ -1838,7 +1837,6 @@ fn test_program_bpf_upgrade_and_invoke_in_same_tx() {
         program_id,
         &[0],
         vec![
-            AccountMeta::new(program_id.clone(), false),
             AccountMeta::new(clock::id(), false),
         ],
     );
@@ -1925,7 +1923,6 @@ fn test_program_bpf_invoke_upgradeable_via_cpi() {
         invoke_and_return,
         &[0],
         vec![
-            AccountMeta::new_readonly(program_id, false),
             AccountMeta::new_readonly(program_id, false),
             AccountMeta::new_readonly(clock::id(), false),
         ],
@@ -2114,7 +2111,6 @@ fn test_program_bpf_upgrade_via_cpi() {
         invoke_and_return,
         &[0],
         vec![
-            AccountMeta::new_readonly(program_id, false),
             AccountMeta::new_readonly(program_id, false),
             AccountMeta::new_readonly(clock::id(), false),
         ],
@@ -2218,7 +2214,6 @@ fn test_program_bpf_upgrade_self_via_cpi() {
         program_id,
         &[0],
         vec![
-            AccountMeta::new_readonly(noop_program_id, false),
             AccountMeta::new_readonly(noop_program_id, false),
             AccountMeta::new_readonly(clock::id(), false),
         ],

sdk/program/src/program.rs

@@ -7,8 +7,6 @@ use crate::{
 /// Notes:
 /// - RefCell checking can be compute unit expensive, to avoid that expense use
 ///   `invoke_unchecked` instead, but at your own risk.
-/// - The program id of the instruction being issued must also be included in
-///   `account_infos`.
 pub fn invoke(instruction: &Instruction, account_infos: &[AccountInfo]) -> ProgramResult {
     invoke_signed(instruction, account_infos, &[])
 }
@@ -19,8 +17,6 @@ pub fn invoke(instruction: &Instruction, account_infos: &[AccountInfo]) -> Progr
 /// - The missing checks ensured that the invocation doesn't violate the borrow
 ///   rules of the `AccountInfo` fields that are wrapped in `RefCell`s.  To
 ///   include the checks call `invoke` instead.
-/// - The program id of the instruction being issued must also be included in
-///   `account_infos`.
 pub fn invoke_unchecked(instruction: &Instruction, account_infos: &[AccountInfo]) -> ProgramResult {
     invoke_signed_unchecked(instruction, account_infos, &[])
 }
@@ -30,8 +26,6 @@ pub fn invoke_unchecked(instruction: &Instruction, account_infos: &[AccountInfo]
 /// Notes:
 /// - RefCell checking can be compute unit expensive, to avoid that expense use
 ///   `invoke_signed_unchecked` instead, but at your own risk.
-/// - The program id of the instruction being issued must also be included in
-///   `account_infos`.
 pub fn invoke_signed(
     instruction: &Instruction,
     account_infos: &[AccountInfo],
@@ -63,8 +57,6 @@ pub fn invoke_signed(
 /// - The missing checks ensured that the invocation doesn't violate the borrow
 ///   rules of the `AccountInfo` fields that are wrapped in `RefCell`s.  To
 ///   include the checks call `invoke_signed` instead.
-/// - The program id of the instruction being issued must also be included in
-///   `account_infos`.
 pub fn invoke_signed_unchecked(
     instruction: &Instruction,
     account_infos: &[AccountInfo],